# CMC-2003
    
    
    INGERSOLL-RAND
    CENTAC
    CMC TECHNICAL REFERENCE MANUAL
    (Part No. 22204796)
    INGERSOLL-RAND
    AIR COMPRESSORS
    CMC TECHNICAL REFERENCE MANUAL
    Copyright Notice
    Copyright 1996-2003 Ingersoll-Rand Company
    THIS MANUAL IS SOLD "AS IS" AND WITHOUT ANY EXPRESSED OR IMPLIED
    WARRANTIES WHATSOEVER.
    Printing Date: 24 March 2003
    Ingersoll-Rand air compressors are not designed, intended, or approved for breathing air
    applications. Ingersoll-Rand does not approve specialized equipment for breathing air
    applications and assumes no responsibility or liability for compressors used for breathing air
    service.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    CMC TECHNICAL REFERENCE MANUAL
    Table of Contents
    What’s New About the 3.10 Release ______________________________________1
    References ___________________________________________________________2
    General - CMC Panel ___________________________________________________3
    Control Methodology___________________________________________________4
    Performance Control _______________________________________________________ 4
    PID Control _______________________________________________________________ 7
    Surge Control ____________________________________________________________ 12
    Prelube Pump ____________________________________________________________ 18
    Oil Heater _______________________________________________________________ 18
    Protection and Monitoring _____________________________________________19
    Analog Functions _________________________________________________________ 19
    Digital Functions _________________________________________________________ 19
    Compressor Operating Methodology ____________________________________21
    Stopped _________________________________________________________________ 21
    Rotating_________________________________________________________________ 21
    Compressor Operating States ______________________________________________ 23
    OUI (Operator User Interface) _______________________________________________ 24
    General Sequence of Operation _____________________________________________ 41
    Indicator, Switch and Light Layout___________________________________________ 42
    CMC Tuning Procedures _______________________________________________42
    Setting MaxLoad__________________________________________________________ 42
    Setting MinLoad __________________________________________________________ 43
    Setting MinLoad Surge Index Increment ______________________________________ 44
    Setting Surge Sensitivity ___________________________________________________ 44
    Tuning Stability __________________________________________________________ 45
    Calibrating the Control Valves ______________________________________________ 46
    Autodual Control Settings __________________________________________________ 47
    Setting the Start Time _____________________________________________________ 48
    Setting the CT Ratio _______________________________________________________ 48
    Inlet Unload Position ______________________________________________________ 48
    Setting Set Point Ramp Rate ________________________________________________ 48
    Alarm and Trip Settings____________________________________________________ 49
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    CMC TECHNICAL REFERENCE MANUAL
    Troubleshooting _____________________________________________________50
    Troubleshooting Example __________________________________________________ 51
    Input/Output (I/O) System __________________________________________________ 52
    Control Power System (CPS) _______________________________________________ 72
    Controller Problems_______________________________________________________ 76
    Options _____________________________________________________________78
    Enclosures ______________________________________________________________ 78
    Control Electrical Package _________________________________________________ 80
    Stage Data Package _______________________________________________________ 80
    Alarm Horn ______________________________________________________________ 80
    Running Unloaded Shutdown Timer _________________________________________ 80
    Water Solenoid Post Run Timer _____________________________________________ 80
    Panel Mounted Wye-Delta Starter ____________________________________________ 80
    N.O. Contact for Remote Indication of Common Alarm and Trip __________________ 80
    Power Regulating Constant Voltage Transformer ______________________________ 80
    Automatic Starting ________________________________________________________ 81
    Remote 4-20 mA Pressure Setpoint __________________________________________ 82
    Ambient Control plus Parallel Valve Control Logic _____________________________ 82
    Mass Flow Control ________________________________________________________ 84
    Steam and Gas Turbine Driven Compressors __________________________________ 85
    Diesel Driven Compressors ________________________________________________ 92
    Communication ______________________________________________________93
    Human Machine Interface (HMI) Systems _____________________________________ 93
    Direct CMC Communications with RS422/485__________________________________ 93
    The CMC-MODBUS Interface________________________________________________ 94
    The CMC-DF1 Interface ___________________________________________________ 115
    Documentation______________________________________________________143
    System Information __________________________________________________143
    Status Codes ___________________________________________________________ 143
    Base Control Module (BCM) _______________________________________________ 145
    Operator User Interface Module (OUI) _______________________________________ 148
    Universal Communication Module (UCM) Optional ____________________________ 152
    Technical Specification_______________________________________________160
    Glossary _____________________________________________________________1
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    CMC TECHNICAL REFERENCE MANUAL
    Table of Figures
    Figure 1: Compressed Air System ................................................................................................................ 4
    Figure 2: Modulate Control .......................................................................................................................... 5
    Figure 3: Autodual Control ........................................................................................................................... 5
    Figure 4: Performance Control..................................................................................................................... 6
    Figure 5: Prpportional Band, Pb................................................................................................................... 7
    Figure 6: Proportional Plus Integral Control................................................................................................. 8
    Figure 9: MinLoad and MaxLoad ............................................................................................................... 10
    Figure 14: Rise to Surge ............................................................................................................................ 14
    Figure 15: Changes in Discharge Pressure............................................................................................... 14
    Figure 16: Surge Detection System ............................................................................................................ 16
    Figure 18: Plant Air System ........................................................................................................................ 42
    Figure 19: Troubleshooting Tree................................................................................................................. 50
    Figure 21: Measuring Flow ......................................................................................................................... 85
    Figure 22: MODBUS Messages................................................................................................................. 95
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    CMC TECHNICAL REFERENCE MANUAL
    What’s New About the 3.10 Release
    This is the initial release of the CMC Manual for version 3.10. This version was created to
    support new features incorporated into the CMC Product, and provide additional
    information compared with previous versions.
    Specifically, new features are as follows:
    1. PID Scaling, p.9
    2. Valve Characterization, p.15
    3. Ambient Control plus Parallel Valve Control Logic, p.82
    4. Mass Flow Control, p.84
    5. Support for new, high speed IR-Bus at 38.4 kbps
    6. Processor upgraded from 16 MHz to 25 MHz on Base Control Module (BCM)
    7. Replaceable fuse (F2) for display, p.149
    8. Operator instructions on display, p.35
    9. “Pop-up” window to provide useful customer information, p.28
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    1
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    CMC TECHNICAL REFERENCE MANUAL
    References
    The following references were used in creating this document. All of this documentation is
    recommended for a more detailed understanding of specific control modes and control
    panel functions.
    NEMA STANDARDS PUBLICATION NO. 250, Enclosures for Electrical Equipment (1000 Volts
    Maximum), Revision 2, May 1988
    NFPA 496 Standard for Purged and Pressurized Enclosures for Electrical Equipment, 1986
    Edition
    Nisenfeld, A. Eli, Centrifugal Compressors: Principles of Operation and Control, Instrument
    Society of America, 1982
    Moore, Ralph L., Control of Centrifugal Compressors, Instrument Society of America, 1989
    Doebelin, Ernest O., Control System Principles and Design, John Wiley & Sons, 1985
    Rowland, James R., Linear Control Systems Modeling, Analysis, and Design, John Wiley &
    Sons, 1986
    Deshpande, Pradeep B. and Ash, Raymond H., Computer Process Control With Advanced
    Control Applications, 2nd Edition, Instrument Society of America, 1988
    CENTAC ENERGY MASTER, Version CEM230, Ingersoll-Rand Company, March 1992
    White, M.H., Surge Control for Centrifugal Compressors, Chemical Engineering, December 25,
    1972
    Hall, James W., THERMODYNAMICS OF COMPRESSION: A Review of Fundamentals,
    Instrument Society of America, 1976
    Gaston, John R., Centrifugal Compressor Operation & Control: Part II "Compressor Operation",
    Instrument Society of America, 1976
    Gaston, John R., Antisurge Control Schemes For Turbocompressors, Chemical Engineering,
    April 1982
    Warnock, J. D., Methods for Control of Centrifugal and Reciprocating Compressors, Moore
    Products, 1984
    Harrison, Howard L. and Bollinger, John G., Introduction to Automatic Controls, Second Edition,
    Harper & Row, 1969
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    CMC TECHNICAL REFERENCE MANUAL
    General - CMC Panel
    The CMC panel is the microprocessor-based control and monitoring system for Centac.
    The CMC handles compressor control and monitoring functions; as well as, control of
    auxiliary equipment such as the main motor starter, oil heater, and prelube pump.
    The CMC panel has a custom computer board called the Base Control Module (BCM). This
    board has a microcontroller and memory chips that tell the rest of the panel what to do for
    the various input pressures, temperatures and vibrations. All hardware for data analysis,
    number of input and output (I/O) points and system memory are optimally selected for
    accurately controlling and protecting Centac compressors.
    Features of the CMC system are:
    •
    Ease of use ... only twelve buttons to push on the operator OUI!
    •
    Multiple function, 240 x 128 pixel graphic LCD to display data, operating status and
    basic operator instructions.
    •
    Unload, Modulate and Auto-Dual operating modes.
    •
    Advanced surge detection and control.
    •
    High current limit for main drive electric motor protection.
    •
    First-out indication and event log to help determine the root cause of a compressor trip.
    •
    Pinion vibration alarm and trip for each compression stage.
    •
    Base Control Module CPU running at 25Mhz.
    •
    Base Control Module, Operator User Interface and Universal Communication Modules
    capable of serial communication at 38,400 baud
    •
    Optional port for communicating to the Air System Controller (ASC), Air System Manager
    (ASM) or other Distributed Control Systems (DCS) via MODBUS protocol.
    •
    Optional reduced voltage motor starter included in panel for some sizes.
    NOTE
    For the purpose of consistency and clarity, all of the descriptions and examples that
    follow refer to "air" for the more generic "gas". Any gas compressed by a Centac
    compressor would also apply.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    3
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    CMC TECHNICAL REFERENCE MANUAL
    Control Methodology
    The CMC utilizes performance and surge control methodologies to meet varying
    compressed air system needs. The term "performance control" is used for grouping the
    control modes that affect compressor power consumption through movement of the intake
    and discharge valves.
    Performance Control
    The CMC has three standard performance control modes or methods of operation. These
    modes are Unload, Modulate and Autodual for typical plant air compressors operating in
    constant pressure applications. For the discussions that follow, Figure 1 depicts a
    compressed air system and the relationship between the compressor and the plant air
    system.
    Atmosphere
    Silencer
    Inlet
    Valve
    Inlet
    Filter
    Bypass
    Valve
    Check
    Valve
    Plant Air System
    Compressor
    Figure 1: Compressed Air System
    Unload
    The compressor is unloaded, when no air is being supplied to the Plant Air System, and all
    of the air produced by the compressor is being vented to the atmosphere. In this mode, the
    inlet valve is slightly open to allow enough air to pass through the compressor for internal
    cooling, prevention of rotor instability and surge avoidance. This air is then discharged
    through the open bypass valve to the atmosphere. Typically, the compressor is set to make
    a positive pressure across the first compression stage, which produces a discharge
    pressure something greater than the atmospheric pressure.
    The inlet valve opening required to create this positive pressure is directly related to the
    horsepower consumed; therefore, careful consideration should be given to this inlet valve
    position for minimizing overall power consumption.
    Modulate
    Constant pressure control is a frequently required performance control method for Centac
    air compressors. If left uncontrolled, the compressor's discharge pressure would rise and
    fall along the natural performance curve as system demand changed. Modulate control
    satisfies the constant pressure requirement.
    The performance map in Figure 2 shows Modulate control. Modulate maintains the system
    discharge pressure at the system pressure set point as entered into the CMC by the user.
    Once loaded, the compressor will operate along the constant pressure line until the user
    switches to Unload or presses the stop button.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
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    CMC TECHNICAL REFERENCE MANUAL
    Control is accomplished by
    modulating the inlet valve within
    the compressor's throttle range.
    When system demand is less
    than the minimum throttled
    capacity, the discharge pressure
    is maintained by modulating the
    bypass valve and venting some
    or all of the air to atmosphere.
    This valve is opened just prior to
    reaching the surge line.
    Whenever the bypass valve is
    open, the inlet valve maintains its
    position at the minimum throttled
    capacity setting. Modulate
    provides a constant discharge
    pressure with variable capacity
    from design to zero.
    Natural
    Pressure
    Curve
    Constant Pressure Line
    Surge Line
    Design
    Point
    Maximum
    Throttle Point
    (MinLoad)
    Discharge
    Pressure
    Unloaded
    Inlet
    Valve
    Throttle
    Range
    Bypass
    Valve
    Throttle
    Range
    Natural
    Power
    Curve
    Surge Line
    Constant Power Line
    Power at
    Coupling
    This control method is used when
    stable control of the discharge
    pressure is required. Modulate is
    the most commonly used control
    method for Centac compressors.
    Unloaded
    Capacity
    Figure 3: Modulate Control
    Energy Saving Control - Autodual
    Autodual automatically loads
    the machine when demand is
    high and unloads the machine
    when demand is low.
    When the compressor is
    controlling to pressure setpoint
    and demand is within the inlet
    valve throttle range, constant
    pressure is maintained in the
    same manner as Modulate.
    When the machine is controlling
    to the pressure setpoint and
    system demand is low, the
    compressor is operated in the
    bypass valve throttle range.
    Autodual automatically unloads
    the machine when the bypass
    valve is opened beyond the
    Unload Point for a programmed
    time period called the Unload
    Delay Time. The Bypass Valve
    Unload Point is selected to
    correspond with the check valve
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Natural
    Curve
    Surge Line
    Unload
    Point
    Design
    Point
    Reload Point
    (Reload Percent)
    Discharge
    Pressure
    Unloaded
    Bypass
    Valve
    Throttle
    Range
    Power at
    Coupling
    Inlet
    Valve
    Throttle
    Range
    Unload
    Point
    Unloaded
    Capacity
    Figure 2: Autodual Control
    Natural
    Curve
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    CMC TECHNICAL REFERENCE MANUAL
    closing since at this point the machine is not supplying the system (Figure 3). The Unload
    Delay Timer should be set to prevent unloading during short excursions through the Unload
    Point. The Reload Percent determines the System Pressure at which the machine will
    automatically load into the system.
    How does Constant Pressure Modulation Work?
    The goal of constant pressure modulation is to maintain a specified discharge pressure in
    the compressed air system while the capacity requirements change. Modulate control
    provides constant pressure from 100 percent of the compressor's capacity to zero capacity.
    Autodual control provides constant pressure from the 100 percent of the compressor's
    capacity to the Unload Point.
    If all plant air systems were identical in capacity usage requirements, the CMC could be
    preprogrammed to respond to those changes; however, all plant air systems are not alike.
    The frequency and variability of the capacity changes means that the control logic must be
    flexible, so the CMC utilizes proportional, integral and derivative control algorithms to
    determine the magnitude of the signal that is sent to the inlet and bypass valves. These
    algorithms, or programming logic, allow the CMC control system to be "tuned" to a specific
    plant air system.
    Measuring the Discharge Pressure
    In order to maintain constant pressure, the system discharge air pressure must be
    measured. A pressure transducer is mounted in the control panel and tubed to the
    compressor discharge downstream of the check valve as shown in Figure 4.
    CMC
    Pneumatic Tubing
    PT
    4-20 mA
    Bypass
    Valve
    Base
    Control
    Module
    4-20 mA
    CT
    Check
    Valve
    Starter
    Motor
    4-20 mA
    PTx
    Compressor
    Inlet
    Valve
    Figure 4: Performance Control
    This transducer sends a 4-20 mA signal to the CMC board. The CMC compares the
    measured discharge pressure to the system pressure set point entered into the CMC by the
    user through the Operator User Interface (OUI). Depending upon the difference between
    these two values the CMC will send a 4-20 mA signal to "Modulate", open or close, the inlet
    and/or bypass valve to maintain the specified system pressure set point.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    7
    CMC TECHNICAL REFERENCE MANUAL
    PID Control
    Proportional Band
    Proportional control varies the signal sent to the valves as a linear response to the
    difference between the actual system pressure and the system pressure set point. Valve
    responsiveness can be adjusted through the CMC with the proportional band, Pb, set point.
    This set point is the controller gain. Gain is a scaling factor. This scaling factor, graphically
    depicted in Figure 5, is the amount of change in the input variable (actual minus set point
    pressures) to cause a full scale change in the output variable (valve position).
    In other words, if the pressure in the air system fluctuates frequently, it would be prudent to
    set Pb to a low value to keep up with those system changes. Otherwise, if the system is
    very stable, a larger value can be used. Pb is directly related to valve life and indirectly
    related to valve cycling; so, as Pb decreases, valve life decreases and cycling increases.
    As stated earlier, the CMC uses a proportional, integral and derivative control algorithm.
    The result of proportional only control is offset from the controlled variable, discharge
    pressure. This means that if the set point pressure is 100, the actual pressure may only be
    95. The value of this offset depends upon the
    proportional band value.
    What is the valve response when the difference
    between actual and set point pressures is zero?
    There is no response. Proportional control only
    functions when a difference or error exists. Design
    discharge pressure could not be attained in a
    proportional only control system. Therefore, an
    integral control algorithm is added to achieve the
    desired discharge pressure.
    Integral Time
    The offset produced by the proportional control
    algorithm could be eliminated by manually
    readjusting the system pressure set point. Using
    the example above, the set point could be reset to
    105 to obtain the 100 desired. Manually resetting
    the set point would be required as the system
    demand fluctuated. Integral control, also known as
    reset control, automatically resets the desired
    system pressure set point. For the CMC, the rate
    at which the controller resets the system pressure
    setting is known as Integral Time, It, and is
    expressed in units of repeats per second.
    Output
    Variable
    (Valve Position)
    Full Scale
    Slow
    Response
    Pb
    0
    Large Change
    Full Scale
    Fast
    Pb low
    Response
    Output
    Variable
    (Valve Position)
    0
    Small
    Change
    If precise control of the specified discharge
    Input Variable
    pressure is required, the It set point should be set
    (Actual - Set Point Pressures)
    for a fast value. It is inversely related to valve life
    Figure 5: Proportional Band, Pb
    and directly related to valve cycling, therefore, as
    It decreases, valve life increases and cycling
    decreases. For the CMC controlling Centac compressors, It values are typically less than
    1.00.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    high
    8
    CMC TECHNICAL REFERENCE MANUAL
    Figure 6 shows the
    relative valve response
    over time for two
    combinations of Pb and It.
    As shown, when Pb is low
    and It is fast, valve activity
    is significant in both
    magnitude and frequency
    to obtain the desired set
    point. The other scenario,
    Pb is high and It is slow,
    has relatively little valve
    activity, and may never
    reach the set point
    position.
    Opened
    Proportional Band - Low
    Integral Time - Fast
    Set Point
    Valve
    Activity
    Proportional Band - High
    Integral Time - Slow
    Proportional Band and
    Closed
    Integral Time are
    Time
    variables used internally
    by the control system to
    determine valve response
    Figure 6: Proportional Plus Integral Control
    and direction for a given
    compressed air system. Each has an optimum value based upon the system's
    characteristics. Determining these optimum values is a trial and error
    exercise. These set points should be re-evaluated any time there is a major change in the
    compressed air system.
    Derivative action depends on the slope
    of the error, unlike P and I. If the error is
    constant derivative action has no effect.
    The derivative term looks at the rate of
    change of the input and adjusts the
    output based on the rate of change.
    Controller
    Output
    Derivative Component
    Proportional Component
    Error
    Derivative Action
    Derivative action (also called rate or preact) anticipates where the process is
    heading by looking at the time rate of
    change of the controlled variable (its
    derivative). TD is the ‘rate time’ and this
    characterizes the derivative action (with
    units of seconds).
    Time
    Figure 7; PD Controller
    Proportional-Integral-Derivative
    When an error is introduced to a PID controller, the controller’s response is a combination
    of the proportional, integral, and derivative actions, as shown in Figure 8.
    Assume the error is due to a slowly increasing process variable. As the error increases, the
    proportional action of the PID controller produces an output that is proportional to the error
    signal. The reset action of the controller produces an output whose rate of change is
    determined by the magnitude of the error. In this case, as the error continues to increase at
    a steady rate, the reset output continues to increase its rate of change. The rate action of
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
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    CMC TECHNICAL REFERENCE MANUAL
    the controller produces an output whose magnitude is determined by the rate of change.
    When combined, these actions produce
    an output as shown in Figure 8.
    On the combined action curve, the output
    is simply the sum of the individual
    Proportional, Integral and Derivative
    corrections.
    Note: The response curves in Figure 8
    are drawn assuming no corrective action
    is taken by the control system.
    With previous CMC versions, PID settings
    could vary considerably depending upon
    the variable regulated. A PID Scaling
    feature has been added to the CMC. This
    feature will provide for more uniform PID
    settings for different process control.
    Up to this point, constant pressure control
    has been accomplished with an analog
    input (system pressure) and two analog
    outputs (inlet valve and bypass valve
    position). In the following paragraphs it
    will be discussed how motor current, the
    other analog input, is used for constant
    pressure control. Also covered in the
    following paragraphs is the discussion as
    to at what time the bypass valve is
    modulated as opposed to inlet valve.
    Error
    Proportional
    Only Action
    Reset
    Only
    Action
    Rate
    Only
    Action
    Combined
    Output
    10%
    5%
    0%
    20%
    10%
    0%
    5%
    0%
    10%
    0%
    55%
    40%
    30%
    T1
    T0
    1 Sec
    T2
    2 Sec
    Figure 8: Proportional-Integral-Derivative
    Motor Current, MinLoad and MaxLoad
    Motor current, in units of power (normally amps), has two functions in the CMC. The first is
    over current protection for the main motor, and is referred to as MaxLoad or High Load
    Limit (HLL). The second function determines the point at which the bypass valve begins to
    modulate for controlling pressure. This point is called MinLoad or Throttle Limit (TL). The
    location of these two points is graphically depicted on the pressure and power versus
    capacity curves as shown in Figure 11.
    MaxLoad or High Load Limit (HLL) setpoint, in units of amps, is a parameter entered into
    the CMC that prevents the main drive motor from overloading. Once this value is reached,
    the CMC logic limits the inlet valve from opening any further. This action constrains the
    motor by limiting the amp draw to the maximum allowable service factor amps by using the
    inlet valve MaxLoad PID loop to maintain the MaxLoad current setpoint as shown in Figure
    9.
    When the motor is sized for cold conditions, there are circumstances when MaxLoad will
    never be reached. For example, the value of MaxLoad as shown in Figure 9, cannot be
    attained for the T=hot curve because it is beyond the maximum compressor capability; that
    is, the inlet valve is fully open. This scenario never limits the inlet valve.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
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    CMC TECHNICAL REFERENCE MANUAL
    When ambient conditions produce the
    T=cold curve, the compressor will
    not be able to achieve the maximum
    capacity because it is beyond the
    MaxLoad value. Since MaxLoad is
    less than or equal to the motor
    nameplate FLA times the adjusted
    service factor, the maximum
    compressor capacity at T=cold could
    only be reached if the motor were sized
    for the T=cold condition.
    MinLoad Control Setpoint in units of
    amps (sometimes referred to as throttle
    limit TL) is the power value at which the
    CMC transfers modulation control from
    the inlet to the bypass valve (Figure
    10). The reason for this transfer is to
    prevent the compressor from entering
    into a surge condition. The bypass
    valve vents air to the atmosphere and
    maintains the pressure setpoint by
    using the bypass valve pressure PID
    loop. At the same time, the inlet valve
    maintains the MinLoad setpoint by
    using the inlet valve MinLoad PID
    loop; therefore, once the MinLoad
    Figure 9: MinLoad and MaxLoad
    Inlet Valve
    Pressure PID
    Control Zone
    HLL
    TL
    Inlet Valve
    MaxLoad PID
    Control Zone
    Power at
    Coupling
    Amps
    Inlet Valve
    MinLoad PID
    Control Zone
    MaxLoad
    Capacity - Mass Flow
    Bypass Valve
    Pressure PID
    Control Zone
    Discharge
    Pressure
    MinLoad
    Power at Coupling
    Discharge Pressure
    Tcold
    Thot
    setpoint is reached, the compressor
    continues to produce a constant amount
    of air. Part of this air goes to the Plant
    Air System, and the remainder is blown
    off. Even though the Plant Air System
    receives only a portion of the air
    produced, the amount of power remains
    constant.
    The following table presents seven
    capacity requirements for a plant air
    system. At each of the capacities, the
    table shows the compressor output,
    valve position, discharge pressure and
    power. Each of these values represents
    a percentage and is only an example. P2
    is the specified discharge pressure and
    P0 is the barometric pressure.
    Capacity - Mass Flow
    Figure 10: MinLoad
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
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    CMC TECHNICAL REFERENCE MANUAL
    System
    Required
    Capacity
    0
    0
    Compressor
    Operating
    State
    Off
    Unloaded
    Compressor
    Output
    Capacity
    0
    10
    Open Position
    Inlet
    Bypass
    Valve
    Valve
    0
    100
    10
    100
    100
    Full Load
    100
    100
    0
    P2
    100
    75
    MinLoad
    75
    70
    0
    P2
    80
    50
    MinLoad
    75
    70
    25
    P2
    80
    25
    MinLoad
    75
    70
    50
    P2
    80
    0
    MinLoad
    75
    70
    100
    P2
    80
    Discharge
    Pressure
    0
    >P0
    Power
    0
    20
    From the table above, once the system required capacity moves below 75 percent, the
    compressor still produces 75 percent capacity with 80 percent of the power. If the system
    needs only 25 percent capacity, it will still have to pay for 80 percent of the power. This is
    why it is important to open the bypass valve at the last possible moment; therefore, setting
    MinLoad properly is critical for efficient energy management.
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    Surge Control
    As stated earlier, setting MinLoad properly is critical for efficient energy management.
    Also, a well thought-out design method of transferring into and out of the MinLoad state
    contributes to good Surge Control. The discussion thus far has only considered motor
    current as the point at which the transition from the Loaded state to the MinLoad state
    occurs. The following sections will consider methods other than motor current as to when
    to transition to the MinLoad state.
    ‘Surge’ - Definition
    Surge is the reversal of flow within one or more stages of a dynamic compressor. This
    reversal takes place when the capacity being handled is reduced to a point where
    insufficient pressure is being generated to maintain positive capacity. This condition can
    potentially damage the compressor if it is severe and is allowed to remain in that state for a
    prolonged period; therefore, control and prevention is required.
    Control Methodology
    Surge prevention is accomplished opening the bypass valve prior to reaching the surge
    point. The point at which the bypass valve opens is MinLoad. By blowing a portion of the
    air to the atmosphere, the compressed air system gets the air that it demands. The
    compressor avoids surge because it is still producing the minimum air capacity.
    The following methods of MinLoad control are available on the CMC.
    Motor Current
    Motor Current, amps
    Amps vary with voltage
    Natural
    Surge
    Points
    MinLoad
    Setpoint
    Curve "marginally" affected by
    changes in inlet temperature at a
    constant inlet pressure
    The most common method
    determining when to transition to the
    MinLoad status is by using motor
    current. Motor current may be
    correlated to flow through the
    compressor. As flow increases
    through the compressor motor
    current increases as well. The most
    significant factor affecting motor
    current is voltage. If voltage
    dropped it would cause current to
    rise even though no change in flow
    occurred. Therefore motor current
    can vary as illustrated in Figure 11.
    Capacity, scfm
    Figure 11: Motor Current Method
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    Motor Power, kW
    Optional Motor Power (kW)
    Another method of determining when to
    transition to MinLoad control on motor
    driven units is by using motor power or
    kilowatts (kW). This method takes into
    account any changes in motor current due
    to the influence of voltage. If voltage drops
    and current rises, kW would remain
    constant. This allows for better correlation
    in flow through the compressor, therefore,
    allowing for more accurate control and
    potentially blowing less air to atmosphere.
    Natural
    Surge
    Points
    MinLoad
    Setpoint
    Curve "marginally" affected by
    changes in T1 at a constant P2
    This method virtually eliminated
    inefficiencies due to changes in voltage.
    Capacity, scfm
    Figure 12: Optional Motor Power, kW
    Optional Ambient Control (Polytropic Head)
    Head, ft-lb/lb
    Another method of determining when to transition to MinLoad control is by using Polytropic
    Head calculation. For purposes of the CMC we refer to this method as Ambient Control.
    Natural
    Surge
    Point
    MinLoad
    Setpoint
    For a given set of
    hardware (impellers
    and diffusers) running
    at a constant speed,
    this curve is fixed
    Curve unaffected by changes in
    T1, P1 or P2
    Capacity, icfm
    Figure 13: Optional Head Control
    Ambient Control calculates the work
    performed by the compressor and is
    expressed in foot-pounds per pound
    of gas (ft-lb/lb). For a given set of
    hardware, the amount of work the
    compressor is capable of is fixed. If
    the compressor is called upon to
    exceed that amount of work, it will
    surge. By knowing the amount of
    work the compressor will do before
    surging a more conservative
    MinLoad point expressed in ft-lb/lb
    may be set.
    The ability to set the MinLoad point
    closer to the surge line allows the
    compressor to throttle more (deeper)
    before blowing air to the atmosphere
    and thus conserving energy.
    Surge Detection
    Even though the CMC controls to prevent surge, it can still occur. Insufficient rise to surge,
    rapid changes in system discharge pressure, and various other reasons exist for a
    compressor to surge.
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    Insufficient Rise To Surge
    Rise to surge is the percentage of the compressor's surge pressure to discharge pressure
    (see Figure 14). When an insufficient rise to surge situation exists, small fluctuations in the
    air system demand and ambient temperature can cause the compressor to surge.
    From Figure 14, when T=cold,
    there is sufficient rise to surge. As
    the ambient temperature increases
    to T=hot, the amount of rise to
    surge decreases because the
    discharge pressure is remaining
    constant and the natural curve is
    changing with temperature.
    T=cold
    Discharge
    Pressure
    Rise
    To
    Surge
    T=hot
    Typically sufficient rise to surge
    exists when a ten- percent rise to
    surge can be achieved for the
    hottest ambient that is expected
    Capacity
    for the site. If this design criterion
    Figure 14: Rise to Surge
    is followed, the control system
    should be able to prevent surge for
    variations in air demand and inlet temperature. The same design methodology applies for
    changes in cooling water temperature for multi-stage compressors.
    Changes in System Discharge Pressure
    MinLoad corresponds to a specific constant discharge pressure; therefore, if the discharge
    pressure changes, MinLoad must
    be reset to properly control surge.
    As shown in Figure 15, when the
    discharge pressure is changed
    from point 1 to 2, a surge can occur
    at point 2 if MinLoad is not reset.
    Changes in system discharge
    pressure also apply, but more
    subtly, when the compressor
    begins to age. Dirty inlet filter
    elements and fouled coolers can
    change the compressor's natural
    curve; so MinLoad should be
    checked periodically to prevent
    surge from an incorrect setting.
    Rapid System Demand Changes
    Discharge
    Pressure
    TL2
    TL1
    Capacity - Mass Flow
    Figure 15: Changes in Discharge Pressure
    When the system demand varies
    rapidly over a wide range of
    capacity, the controller may not react fast enough to open the bypass valve to prevent
    surge. The CMC reads discharge pressure, motor amps, and approximately twenty other
    pressure and temperature inputs; plus controls the inlet and bypass valve position. The
    time required to do all of this approximately 100 milliseconds. When the controller is too
    slow to react, it is referred to as "driving through MinLoad". The only prevention for a
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    CMC TECHNICAL REFERENCE MANUAL
    situation like this is to set MinLoad at a more conservative value. The only negative
    implication to this is reduced energy savings, because the bypass valve is opened early.
    Incorrect Instrumentation Output
    If the instrumentation, defined in Figure 4, is improperly calibrated or gives inaccurate
    readings, the compressor could surge even though the CMC thinks it should not. Areas of
    concern are insufficient power air, incorrect valve transducer calibration, and repeatability of
    both inlet and bypass valves. If the valves are being sent signals for specific movements
    and they do not respond by moving to the new positions, then the CMC has very little
    chance of correctly controlling surge, or even the discharge pressure.
    As discussed earlier, the CMC uses motor current as the standard method for determining
    when to open the bypass valve. The time to begin opening the bypass valve is near
    MinLoad amps. The equation,
    GHP=
    I× V× η
    × PF× 3
    motor
    746
    indicates that horsepower is directly related to current; it is, but it is also related to voltage.
    This is not normally a concern because voltage is primarily constant. However, there are
    some locations where extreme voltage variations do exist. In these circumstances, the
    CMC cannot correctly determine when it reaches MinLoad and a surge can occur. For
    these applications, an optional watt transducer can be used to avoid this situation.
    Incorrect Valve Response
    Valve Characterization is available on the CMC. Valve characterization allows a more
    linear use of the valve throttling characteristics. Linear flow is a flow characteristic in which
    the valve relative opening directly correlates to the percentage flow, e.g. a 50 % open valve
    gives 50% of maximum flow, with a constant pressure drop across the valve. The CMC
    modifies the controller output to allow a more linear response to valve throttling. This
    feature requires configuration by an Ingersoll-Rand service technician.
    How is Surge Detected?
    Note that it has been shown that even though the CMC has surge prevention logic, a surge
    can still occur. The CMC has a surge detection system comprised of a surge pressure
    transducer and motor current transformer (see Figure 16). The CMC senses surge when
    the rate of change in last stage discharge pressure and the rate of change in motor current
    are greater than the surge sensitivity setpoint value. When this occurs, the CMC will alarm
    and unload the compressor.
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    Pneumatic Tubing
    CMC
    PT
    4-20 mA
    Bypass
    Valve
    Base
    Control
    Module
    4-20 mA
    CT
    Check
    Valve
    Starter
    Motor
    4-20 mA
    PTx
    Compressor
    Inlet
    Valve
    Figure 16: Surge Detection System
    Surge AbsorberTM
    When the controller recognizes that a surge occurred, the compressor will unload. With the
    Surge AbsorberTM feature enabled, the controller will increment the bypass valve position
    by a fixed percentage, send the inlet valve to the MinLoad point (if it is not already there)
    and then let normal system demand reload the compressor to the operating pressure. This
    process will repeat up to three times within a ten-minute period. If the compressor surges
    four times in ten minutes, the compressor will remain unloaded until an operator presses
    the reset button. Each detected surge drives a Surge Event to the Event Log. If the
    compressor unloads due to repeated surges, a Surge Unload Alarm Event is driven to the
    Event Log.
    Surge Indexing
    MinLoad
    Surge
    Index
    Increment
    Discharge
    Pressure
    MinLoad User Setpoint
    MinLoad Control Setpoint
    (reset returns control here)
    Power at
    Coupling
    Amps
    MinLoad Control Setpoint #3
    (currently active)
    MinLoad Control Setpoint #1
    MinLoad Control Setpoint #1
    Capacity - Mass Flow
    Since the setting of MinLoad
    Control Setpoint is sensitive
    to many variables in a
    compressed gas system,
    there is potential for the
    setting to require adjustment
    throughout the operation of
    the compressor. When
    MinLoad is set incorrectly,
    one of two things can
    happen. When MinLoad is
    set too high, the compressor
    will consume excessive
    power at MinLoad. When
    MinLoad is set too low, the
    compressor is allowed to go
    past the surge line and
    surge occurs.
    Figure 17: Surge Indexing
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    When Surge Indexing is enabled, it corrects the situation when MinLoad is set too low by
    automatically adjusting MinLoad to a higher value upon a surge. The indexed setting,
    MinLoad Control Setpoint will remain in effect until MinLoad User Setpoint is Operator User
    Interface, or the Reset button is held for more than five seconds. When MinLoad User
    Setpoint is manually changed, the MinLoad Control Setpoint is automatically changed to
    match the new setting, and when reset, the MinLoad Control Setpoint is reset to the new
    MinLoad.
    Entering a zero into the MinLoad Surge Index Increment variable disables surge Indexing.
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    Oil System Control
    The CMC panel provides control of the prelube pump and lube oil heater in the starting
    sequence, during normal operation and after compressor stops or trips.
    Prelube Pump
    The prelube pump is started when the panel power is on and seal air is present. The
    prelube pump stops after the compressor start button is pushed and the programmable
    timer “Start Time” has expired. The pump does not come on again until the Stop key is
    pressed, and will remain on until the panel power is turned off or Seal Air is lost.
    Oil Heater
    The oil heater is thermostatically controlled. When the oil temperature is below the set point
    temperature, the oil heater is energized, above the set point temperature it is de-energized.
    The oil heater control does not have any interaction with the microprocessor board and is
    designed to operate with the control panel de-energized as long as three-phase power is
    available.
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    19
    Protection and Monitoring
    Each CMC base module has twenty-three analog inputs, sixteen digital inputs, four analog
    outputs and sixteen digital outputs for control, protection and monitoring. These input
    functions provide the CMC with information about the compressor. The CMC board uses
    the output functions to communicate to the user and perform actions like starting the
    compressor and turning on the prelube pump. All of these inputs and outputs are required
    to interface physical actions to and from the electronics.
    Analog Functions
    An analog function is one in which an electrical signal represents a specific pressure,
    temperature, vibration and current input; or valve position output. As these inputs and
    outputs fluctuate, the electrical signal to and from the microprocessor board also fluctuates
    proportionally to the amount of change.
    Analog Inputs
    Twenty-one grounded and two floating analog inputs are used for protection, monitoring
    and control. Each input used for protecting the compressor can be programmed for alarm
    and trip indication. Each of these functions is pre-programmed with the function title,
    engineering units, range, alarm and trip values, so no configuration is required upon receipt
    by the customer.
    The CMC uses pressure transmitters to measure pressure, resistance temperature
    detectors (RTD) and transmitters to measure temperature, eddy current based vibration
    transmitters to measure shaft vibration and a current transformer to measure the motor
    current.
    The CMC logic used for the protective alarm and trip functions is as follows: if the actual
    value of the input is greater than or equal to the alarm or trip value, indicate the condition.
    This logic is used for all inputs except, low oil pressure and low oil temperature where the
    logic is reversed. To prevent nuisance alarms and trips, all standard analog inputs use an
    alternate alarm and trip value during the stopped, starting, and coasting states. The
    alternate setpoints cannot be edited through the Operator User Interface.
    Analog Outputs
    Two of the available four analog output functions are for inlet and bypass valve positioning.
    These are only output functions. The standard configuration for a CMC has no input
    information as to the valve location. The CMC calculates the position based upon where the
    valves are supposed to be and sends those signals to the valves.
    Digital Functions
    A digital function is one in which the presence of an electrical signal indicates ON or YES,
    and the lack of that signal represents OFF or NO. This is analogous to a light switch that
    has only two states, ON or OFF. The term "discrete" is also used instead of digital in many
    instances. The term that will be used throughout this documentation shall be digital.
    Digital Inputs
    The sixteen digital inputs provide status of field switches. Emergency Stop and Low Seal
    Air Pressure trip are standard. Any of these inputs can be configured as an alarm or trip. All
    inputs operate on 24 VDC power.
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    Digital Outputs
    The sixteen digital outputs are used by the CMC to start the prelube pump, energize the
    main starter contacts, indicate that an alarm or trip condition exists, indicate that the
    compressor is unloaded, activate the running unloaded shutdown timer and to sound the
    horn. Outputs can operate on 120 VAC, 60 Hz, single-phase power or 24 VDC power.
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    21
    Compressor Operating Methodology
    In the following description of compressor operation, the term “state” is used to indicate
    what the compressor is doing, or mode of operation, at any given time. These operating
    states exist in a hierarchy. For example, the two highest level states are “Stopped” and
    “Rotating”. All other states exist at a level below these two states.
    Compressor Operating States
    Waiting
    This state implies that the compressor is
    NOT rotating. It is important to note that this
    is an implication only. If the instrumentation
    is not working properly or the system is setup
    improperly, the compressor could be rotating.
    Not Ready
    Waiting
    Ready
    After the panel power is energized, the
    controller starts the Waiting Timer and does
    not allow further User operation until after the
    timer expires. This timer is set at the factory
    for two minutes (120 seconds) and is not
    adjustable. This period allows the
    compressor prelube pump to circulate oil
    throughout the casing and prevents
    restarting while the compressor is coasting
    down after an electrical interruption.
    Motor Driven Packages
    +
    Compressor
    +
    +
    Stopped
    Stopped
    Rotating
    Starting
    Unloaded
    A-D Unloaded
    Surge Unload
    Loading
    MinLoad
    Loaded
    Full Load
    Not Ready
    When in this state, the compressor is “Not
    Ready To Start”. This state is entered when
    Unloading
    the Waiting Timer has expired and any time
    Coasting
    that a compressor trip has been identified. A
    very common and quite often overlooked
    reason for the compressor being “Not Ready” is when the Emergency Stop push button has
    been engaged. This state can exist indefinitely.
    MaxLoad
    Ready
    Similar to the previous state, this state could be redefined as “Ready to Start”. This state is
    entered when all compressor permissive functions have been satisfied. This state can exist
    indefinitely.
    Rotating
    This mode does not necessarily mean that the compressor is actually rotating. It means that
    it is possibly rotating or rotation is pending and expected.
    Starting
    Any time after the compressor is ready and a start command is given, this state is entered.
    The goal for this period is to get the compressor to rated speed and running unloaded.
    “Starting” is allowed for only the Start Timer period and is adjustable. This time period is
    limited to a maximum of one minute, or 60 seconds. The reason for the limit is to prevent
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    CMC TECHNICAL REFERENCE MANUAL
    the compressor from operating in the critical speed for an extended period. Stage vibration
    alarm and trip setpoints are increased during this period to get the compressor through the
    critical speed region. After the compressor has “Started”, the alarm and trip setpoints are
    adjusted back to their original values. The same procedure occurs for stage air temperature
    also.
    This state exits only after the Starting Timer has expired. THE COMPRESSOR IS ALWAYS
    STARTED UNLOADED. On exit of “Starting”, the compressor will return to the mode that it
    was in the last time it ran. For example, typical operation implies that prior to stopping the
    compressor, the Unload key is pressed. If this occurred, then the compressor will remain in
    “Unload” after starting. If the compressor was running and tripped, the compressor will
    automatically return to the “Loaded” mode on exit of the Starting state. The User may also
    press the Load or Unload key prior to pressing the Start key to force the compressor to into
    either post-Starting state.
    Unloaded
    The compressor is in this state after a start (and Load Selected is not in effect) or when the
    User issues an unload command. A-D Unloaded and Surge Unload are also considered
    states. However, these two states are really just reasons for being in the Unloaded state. AD Unloaded means “AutoDual Unloaded” which occurs when AutoDual is enabled and the
    system pressure has been high enough for a long enough time to drive an unload
    command. “Surge Unload” is similar in that a surge event drives the unload command
    instead of AutoDual. These states can exist indefinitely.
    Loading
    When a valid load command is issued, the compressor will enter this state. This state exists
    until the MinLoad state is satisfied. The duration of this state depends upon PID settings for
    the inlet valve at the MinLoad state and the demand for air.
    MinLoad, Loaded, Full Load and MaxLoad
    These states transition among themselves as demand for air changes. “MinLoad” means
    that the bypass valve is controlling pressure and the inlet valve is maintaining the MinLoad
    Control Setpoint. “Loaded” means that the inlet valve is controlling pressure and the bypass
    valve is closed. “Full Load” occurs when the inlet valve has reached the full open or 100%
    position. “MaxLoad” means that the inlet valve is maintaining the MaxLoad Setpoint to
    prevent motor damage. In both the “Full Load” and “MaxLoad” states, system pressure may
    be lower than setpoint pressure.
    Unloading
    This state occurs when a valid Unload command is issued and will persist until the
    compressor reaches the Unloaded state.
    Coasting
    When a trip or any stop command is issued and the compressor is running, the motor will
    be de-energized and the compressor will begin to coast to a Stopped state. This state will
    remain as long as the adjustable Coast Timer is in effect. At the end of the timer, the
    compressor will enter either the Ready or Not Ready state.
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    CMC TECHNICAL REFERENCE MANUAL
    WARNING
    Failure to set the Coast Timer for a period greater than or equal to the actual
    coasting time can result in compressor damage.
    Compressor Operating States
    The following diagrams graphically depict the states relative to valve position. This diagram
    is provided to assist in the understanding of overall compressor operation.
    Compressor Operating States
    Coasting
    Unloaded
    Unloading
    MaxLoad
    Loaded
    Full Load
    Loaded
    MinLoad
    Loading
    Starting
    Unloaded
    Ready
    Not Ready
    Waiting
    with Valve Position
    System Pressure Setpoint
    Inlet
    Valve
    Bypass
    Valve
    System Pressure
    milli
    amps
    %
    100 20
    4
    100
    75 16
    8
    75
    12
    50
    16
    25
    20
    0
    %
    milli
    amps
    Unload
    50 12
    Stop
    or Trip
    Tight Closure
    25
    8
    0
    4
    Load
    Start
    Inlet Valve Unload Position
    Power
    On
    Stopped
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    Rotating
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    CMC TECHNICAL REFERENCE MANUAL
    User Interface
    OUI (Operator User Interface)
    User interface is defined as the means by which people interact with the compressor
    control system. The standard configuration of the CMC has two components of the user
    interface. They are the OUI and the device plate. The key component of "easy to use" is
    that there are only twelve buttons to press on the OUI and four buttons, lights, and switches
    on the device plate.
    The CMC OUI consists of six command buttons (Start, Stop, Load, Unload, Acknowledge
    and Reset), four navigation keys (Up, Right, Left and Down), an Edit mode selection key
    (Enter) and a Contrast key. These keys in conjunction with the 240x128-pixel graphics
    display make up the user interface to the compressor. The bezel that surrounds the OUI
    ensures that the NEMA 4 rating is maintained for the OUI.
    CENTAC Microcontroller
    SYSTEM
    System
    Pressure
    Pressure
    Setpoint
    INFO
    SETTINGS
    105.3
    105.0
    173.4
    Motor
    Current
    Running Hours 11445
    Loaded
    Inlet
    Valve
    Bypass
    Valve
    22JUL96
    95
    0
    12:00:00
    Load Selected
    Remote
    1/2
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    25
    Command Keys
    These keys “command” the compressor to perform actions as specified in the following
    table. When any of these keys are pressed the action will be logged in the event log.
    Key
    Name
    Acknowledge
    Reset
    Function
    Silences the optional horn or
    acknowledges an alarm.
    Clears all trip latches. Required to be
    pressed after a trip condition to restart
    the compressor.
    Starts the compressor.
    Start
    Stop
    Load
    Stops the compressor. This button
    should be pressed instead of the E-Stop
    for normal operation.
    Engages Modulate or Autodual control
    mode.
    Unloads the compressor.
    Unload
    Enter Key - Display Operating Mode
    The Enter key toggles the display between the NAVIGATION mode and the EDIT mode.
    Navigation Keys
    The arrow keys for Up, Right, Left and Down perform differently depending upon the current
    display-operating mode.
    FOLDER NAVIGATION
    To move among the tabbed folders, press the RIGHT or LEFT key. The folder list is
    circular; that is, when the SYSTEM folder is displayed and the LEFT key is pressed, the
    SETTINGS folder becomes active. The same is true when the SETTINGS folder is
    displayed and the RIGHT key is pressed, the SYSTEM folder becomes active.
    PAGE NAVIGATION
    To move among each folder’s pages, press the UP and DOWN keys. The page list is also
    circular. So, when page 1/4 (pronounced page 1 of 4) is active and the UP key is pressed,
    page 4/4 becomes active. Also, when page 4/4 is active and the DOWN key is pressed,
    page 1/4 becomes active. The current page for a folder is persistent. For example, if you
    begin on the SYSTEM folder page 2, change to the INFO folder and return to the SYSTEM
    folder, page 2 will be the page displayed.
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    Contrast Key
    This key changes the contrast of the backlight for the graphic LCD display. Pressing this
    key steps among each of the thirty two contrast levels. When stepped to the thirty second
    level, pressing the key again returns to the first contrast level.
    Graphic Display
    The 240x128-pixel graphic display allows us to provide a flexible interface between the user
    and the compressor. The display has three distinct regions as shown in the diagram below.
    Folders
    SYSTEM
    Page
    System
    Pressure
    Pressure
    Setpoint
    Motor
    Current
    Status Bar
    INFO
    SETTINGS
    105.3
    105.0
    173.4
    Loaded
    Compressor
    Operating
    State
    Inlet
    Valve
    Bypass
    Valve
    22JUL96
    95
    0
    12:00:00
    Load Selected
    Remote
    1/2
    Compressor
    Control
    Location
    Page Number
    Compressor
    Status
    Graphics Display Area Definitions
    Folder and Page
    In the design of this system, it is important to provide much of the information required for
    operating and troubleshooting the compressor. The tabbed folder with multiple pages
    metaphor has been used to reduce the complexity of a traversing at least sixteen pages of
    information. For the standard design, the maximum number of keys required to get to any of
    the sixteen pages is six. The SYSTEM folder provides information about the compressor
    system, the INFO folder gives various types of information about the unit and the
    SETTINGS folder is used to perform compressor setup.
    Status Bar
    The Status Bar provides four distinct types of information (Compressor Operating State,
    Compressor Status, Compressor Control Location and Page Number). This region is
    always visible from any folder and page combination.
    This Field is displayed in large text so that the operator can determine the compressor’s
    current operating state at a glance. See Section titled “Compressor Operating Methodology”
    for a list of the messages provided.
    The Compressor Status Field messages are Trip, E-Stop (emergency stop button
    pressed), RMT-Stop (a remote stop has been pressed), Start Disabled (an optional
    permissive start condition has not been satisfied), Alarm, Unload Selected (the
    compressor will stay in “Unload” after “Starting” has been completed), and Load Selected
    (the compressor will go to “Minload” after “Starting” has been completed).
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    CMC TECHNICAL REFERENCE MANUAL
    The Compressor Control Location Field messages are Local, Remote (remote hardwired
    commands i.e. start, stop, load, unload etc.), Network (MODBUS, DF1 or ASC
    communication with a UCM) and Remote/Net (both Remote and Network). This indication
    is provided to indicate to the operator that a remote location is in control of the compressor
    and the compressor may start, stop, load, unload, etc. without the local operator initiating
    any commands.
    These three fields combine to provide the operator with the necessary information to create
    a cursory determination of the status of the compressor. When a more thorough
    determination is required, the operator can get additional detail by looking through the other
    pages in the system.
    The Page Number indicates the current page for the current folder with the number of
    pages in the folder. The number of pages is given so that the user always knows where he
    is in the system.
    Navigation Mode
    Navigation mode is active when a folder name (SYSTEM, INFO or SETTINGS) is
    highlighted.
    Edit (Setpoint Changes) Mode
    Edit mode is activated by pressing the ENTER key. In Edit mode one can change
    Setpoints for a page. Once in this mode, the highlight will move from around the folder
    name to the item to be changed. Use the Right and Left arrow keys to move among the
    changeable items and the Up and Down arrow keys to change the value of the item. When
    changes are complete, press the Enter key again to return to Navigation mode.
    Scroll Mode
    Scroll mode is activated by pressing the ENTER key when a folder name INFO is
    highlighted and the Event Log or the Routine Start / Stop page is visible. The Scroll mode
    is used to page through the event log. To move among the pages, press the UP or DOWN
    keys. To deactivate the Scroll mode, press the Enter key.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    27
    28
    CMC TECHNICAL REFERENCE MANUAL
    Pop-up Message
    In the event of an Alarm or Trip, a pop-up message will appear providing the customer with
    the phone number of the local Ingersoll-Rand representative. If the event is a Trip, the
    event log on the SYSTEM folder will be displayed with the pop-up message centered over
    the displayed page. The message may be removed by pressing the ENTER key. The
    following are examples of the pop-up message in the event of an Alarm or Trip.
    Alarm Example
    SYSTEM
    INFO
    SETTINGS
    105.1
    100
    Pressure
    0
    Setpoint 105.0
    Motor
    323.4
    Current
    Press ENTER key to continue
    System
    Pressure
    Inlet
    For Parts orValve
    Service
    Please Call:Bypass
    Valve
    39 02 950 56499
    Running Hrs: 11445
    Loaded
    31-AUG-1999 12:00:00
    Load Selected
    Remote
    1/4
    Trip Example
    SYSTEM
    1
    2
    3
    4
    5
    6
    7
    INFO
    SETTINGS
    Event Name
    Time
    Date
    Low Oil Pressure
    09:18:44 0720
    For PartsTrip
    or Service
    Low Oil Pressure
    Alarm
    09:18:43 0720
    Please Call:
    Reset key pressed
    09:18:34 0720
    39 02 950Trip
    56499 09:08:43 0720
    Low Oil Pressure
    Low Oil Pressure Alarm
    08:58:23 0720
    LoadPress
    key pressed
    08:24:01 0720
    ENTER key to continue
    Start key pressed
    08:23:12 0720
    Not Ready
    Trip
    Remote
    2/3
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    29
    CMC TECHNICAL REFERENCE MANUAL
    SYSTEM Folder
    SYSTEM
    System
    Pressure
    Pressure
    Setpoint
    Motor
    Current
    INFO
    105.1
    105.0
    323.4
    Inlet
    Valve
    Bypass
    Valve
    Temperature
    95.8
    93.5
    115.3
    80.1
    Load Selected
    Remote
    2/4
    Loaded
    INFO
    RESET
    SETTINGS
    Digital Inputs
    Starter Feedback
    E-Stop Pressed
    Low Seal Air
    INFO
    SETTINGS
    Digital Outputs
    Prelube Pump Running
    CR1
    Remote Trouble
    SYSTEM
    CONTRAST
    UP
    RIGHT
    DOWN
    1
    2
    3
    4
    5
    6
    7
    INFO
    SETTINGS
    Event Name
    Low Oil Pressure Trip
    Low Oil Pressure Alarm
    Reset key pressed
    Low Oil Pressure Trip
    Low Oil Pressure Alarm
    Load key pressed
    Start key pressed
    Not Ready
    SYSTEM
    INFO
    SYSTEM
    Date
    0720
    0720
    0720
    0720
    0720
    0720
    0720
    Trip
    Remote
    2/6
    Load Selected
    Remote
    3/6
    SETTINGS
    39 02 950 56499
    Loaded
    Load Selected
    Remote
    4/4
    SYSTEM
    Navigation and
    Enter Keys
    Load Selected
    Remote
    4/6
    Ready
    R E P
    Part No.
    12345678
    12345678
    12345678
    12345678
    12345678
    12345678
    INFO
    Load Selected
    Remote
    5/6
    Ready
    SYSTEM
    INFO
    SETTINGS
    Ready
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Load Selected
    Remote
    6/6
    100.0
    100.0
    1.0
    9.0
    Load Selected
    Remote
    2/6
    INFO
    SETTINGS
    PB
    Inlet Valve
    Pressure
    MinLoad (TL)
    MaxLoad (HLL)
    Bypass Valve
    Pressure
    10.00
    25.00
    99.99
    10.00
    INFO
    IT
    rep/sec
    D
    sec
    0.50
    0.50
    0.50
    0.00
    0.00
    0.00
    0.50
    0.00
    Load Selected
    Remote
    3/6
    Loaded
    SETTINGS
    Control Mode
    Manual
    Modulate
    Autodual
    Reload Pressure, % of Setpoint
    Unload Point, BV % Open
    Unload Delay Time, seconds
    INFO
    SETTINGS
    Starting Timer, seconds
    Coasting Timer, seconds
    CT Ratio
    Inlet Unload Position, %
    Setpoint Ramp Rate, pressure/scan
    SETTINGS
    Stage 1 Temperature
    Stage 1 Vibration
    Stage 2 Temperature
    Stage 2 Vibration
    Oil Pressure
    High Oil Temperature
    Low Oil Temperature
    Loaded
    20
    240
    60
    15
    5.0
    Load Selected
    Remote
    5/6
    Loaded
    INFO
    98
    1
    1
    Load Selected
    Remote
    4/6
    Loaded
    SYSTEM
    R O U T I N E
    S T A R T / S T O P
    Prior to starting, the operator should
    become familiar with the operation of
    the main driver. Refer to the driver
    manufacturer's instructions in the
    Operation Manual. The operator should
    also be familiar with all the accessory
    and optional equipment contained on the
    400.0
    Loaded
    SYSTEM
    SETTINGS
    L A C E M E N T
    P A R T S
    Description
    Inlet Filter Element Primary
    Inlet Filter Element Secondary
    Oil Filter
    Demister Element
    Lubricant, 55 gallon drum
    Lubricant, 5 gallon drum
    SETTINGS
    Surge Absorber Enabled
    Surge Sensitivity
    SYSTEM
    For parts or service contact your
    local Ingersoll-Rand representative
    at the following number:
    INFO
    MaxLoad (HLL)
    MinLoad
    User Setpoint (TL)
    Control Setpoint
    Surge Index Increment
    SYSTEM
    12338
    11445
    11223
    35
    2.51
    INFO
    *
    1999/08/31
    12:30:00
    Load Selected
    1/6
    Remote
    Loaded
    SYSTEM
    Time
    09:18:44
    09:18:43
    09:18:34
    09:08:43
    08:58:23
    08:24:01
    08:23:12
    SETTINGS
    Loaded
    SETTINGS
    Date, yyyy/mm/dd
    Time, hh:mm:ss
    Load Selected
    Remote
    1/6
    Loaded
    INFO
    Password
    * * *
    Setpoint Changes Enabled
    Language and Units
    English
    degF mils amps psi
    English
    degC mils amps kg/cm2
    ENTER
    STOP
    BCM Ver:
    SYSTEM
    UNLOAD
    Power On Hours
    Running Hours
    Loaded Hours
    Number of Starts
    Load Selected
    Remote
    3/4
    Loaded
    LOAD
    SETTINGS Folder
    SETTINGS
    LEFT
    SYSTEM
    Vibration
    0.25
    0.22
    INFO
    HORN SILENCE
    START
    SETTINGS
    Pressure
    Stage 1
    30.1
    Stage 2 106.6
    Oil
    18.8
    Water
    SYSTEM
    100
    0
    31-AUG-1999 12:00:00
    Load Selected
    Remote
    1/4
    Loaded
    INFO
    SYSTEM
    SETTINGS
    Running Hrs: 11445
    SYSTEM
    INFO Folder
    Alarm
    Trip
    120
    125
    0.80
    1.00
    120
    125
    0.75
    0.95
    18
    16
    120
    125
    100
    95
    Load Selected
    Remote
    6/6
    30
    CMC TECHNICAL REFERENCE MANUAL
    SYSTEM Folder
    The SYSTEM folder provides information about the compressor system. The number of
    pages in this folder is at least four; but could be more for two stage machines with special
    analog options purchased, or for
    compressors with three stages or
    SYSTEM
    INFO
    SETTINGS
    more.
    System
    Pressure
    105.1
    105.0
    323.4
    Inlet
    Valve
    100
    0
    This page shows the main
    compressor operating parameters,
    running hours, date and time. The
    Motor
    System Pressure and Pressure
    Current
    Setpoint are in units as defined by
    31-AUG-1999 12:00:00
    Running Hours: 11445
    the Settings page, Motor Current is
    Load Selected
    in Amps and valve positions are in
    Remote
    1/4
    percent open. Pressure Setpoint is
    always editable while the Inlet and
    System Folder – Page 1: System Pressure
    Bypass Valve positions are edit
    enabled when in the Manual mode
    only. These are the only editable settings in any folder other than the Settings Folder.
    Pressure
    Setpoint
    Bypass
    Valve
    Loaded
    Info Folder Page 1 Edit Parameters Table
    Variable
    Pressure Setpoint
    Minimum
    Value
    Maximum
    Value
    Step
    Size
    0.0
    999.9
    0.1
    Units
    pressure
    Inlet Valve Position (manual mode only)
    percent
    0
    100
    1
    Bypass Valve Position (manual mode only)
    percent
    0
    100
    1
    The Analog Input page provides the
    actual value for each stage pressure,
    temperature and vibration, oil pressure
    and temperature. If additional analog
    inputs have been purchased or more
    stages exist as standard, it is likely that an
    additional page or pages will be added.
    The units are as defined by the Settings
    page. There are no editable setpoints on
    this page.
    The Digital Input page shows the current
    state of the digital (discrete) inputs for the
    system. The number of inputs will vary
    depending upon the number of optional
    inputs purchased. A check in the box to
    the left of the text indicates a TRUE
    condition, whereas, no check indicates a
    FALSE condition. For example, a check
    mark in the “E-Stop Pressed” boxed
    means that the Emergency Stop push
    button has been pressed. It is possible to
    have multiple Digital Input pages.
    SYSTEM
    INFO
    Press
    30.1
    106.6
    20.3
    Stage 1
    Stage 2
    Oil
    Loaded
    SYSTEM
    SETTINGS
    INFO
    Temp
    95.8
    93.5
    105.5
    Vib
    0.25
    0.22
    Load Selected
    Remote
    2/4
    SETTINGS
    Digital Inputs
    Starter Feedback
    E-Stop Pressed
    Low Seal Air
    Loaded
    Load Selected
    Remote
    3/4
    System Folder - Pages 2,3: Analog/Digital Inputs
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    31
    CMC TECHNICAL REFERENCE MANUAL
    SYSTEM
    INFO
    SETTINGS
    Digital Outputs
    Prelube Pump Running
    CR1
    Remote Trouble
    Loaded
    Load Selected
    Remote
    4/4
    System Folder - Page 4: Digital Outputs
    The Digital Output page is similar
    to the Digital Input page except
    that it shows the current state of
    the digital (discrete) outputs for the
    system. The number of outputs will
    vary depending upon the number
    of optional items purchased. A
    check in the box to the left of the
    text indicates a TRUE condition,
    whereas, no check indicates a
    FALSE condition. It is possible to
    have multiple Digital Output pages.
    The SYSTEM folder’s four pages
    give the current operating status for the compressor. The User is always within two
    keystrokes of all operating parameters.
    INFO Folder
    The INFO folder contains the OUI key map, the compressor event log, the hour meters, the
    phone number to call for parts or service, a list of part numbers for consumable parts and
    routine start/stop and
    maintenance instructions. There
    INFO
    SETTINGS
    SYSTEM
    are no editable setpoints in this
    Event Name
    Time
    Date
    folder. The OUI key map will be
    1 Low Oil Pressure Trip
    09:18:44 0720
    the default page on power up.
    2 Low Oil Pressure Alarm
    09:18:43 0720
    The keys are labeled in English
    3 Reset key pressed
    09:18:34 0720
    4
    Low
    Oil
    Pressure
    Trip
    09:08:43 0720
    and the local language,
    5 Low Oil Pressure Alarm
    08:58:23 0720
    depending upon the current
    6 Load key pressed
    08:24:01 0720
    language selected.
    7 Start key pressed
    08:23:12 0720
    Trip
    The Event Log details the last
    Remote
    2/6
    two-hundred twenty four (224)
    “events” that have occurred.
    Each “event” has a date and time
    Info Folder - Page 2: Scrollable Event Log
    stamp. This log will list all Alarms
    and Trips and provides first-out indication. Any time an Alarm or Trip is indicated on the
    Status Bar, the detail for that fault is included here.
    Not Ready
    The event labeled as “1” is the newest event and “7” is the oldest event. For events that
    have identical Time and Date values, the order is still correct (newest to oldest, top to
    bottom). Once the list is full, each new event knocks off the last event.
    Pressing the Enter key to initiate Scroll Mode allows access to events 17 through 224.
    Scroll Mode is indicated by the reverse video of the event numbers. Each Down Arrow
    press displays the next seven events. An Up Arrow press will display the previous seven
    events. Any time a Trip occurs, the system will send the display to the first seven events.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    32
    CMC TECHNICAL REFERENCE MANUAL
    Possible Events List
    Event Name
    Description
    * * End of List * *
    Displayed for the event name whenever the event list is not full.
    A/I Alarm
    The actual value for Analog Input “AI” is greater than the Alarm value.
    A/I Trip
    The actual value for Analog Input “AI” is greater than the Trip value.
    Acknowledge (Location)
    An Acknowledge command has been issued from Location.
    Auto Dual Mode Enabled
    The Auto Dual Mode has been enabled
    Auto Start
    An automatic start occurred (typically from Auto Hot or Cold Start).
    Auto Stop
    An automatic stop occurred (typically from Running Unloaded Shutdown Timer).
    BCM 2 Failure Alarm
    Communications have been lost to Base Control Module #2.
    BCM 3 Failure Alarm
    Communications have been lost to Base Control Module #3.
    Compressor Started
    The compressor has started.
    DI Alarm
    The Discrete Input “DI” is in an alarm condition.
    Discrete Surge
    A discrete surge switch has detected a surge.
    DI Trip
    The Discrete Input “DI” is in a trip condition.
    Driver Trip
    Drive controller feedback was not received after a start command was issued
    Edit-x AI Alarm SP
    The Analog Input “AI” Alarm setpoint value has been edited from location x.
    Edit-x AI Trip SP
    The Analog Input “AI” Trip setpoint value has been edited from location x.
    Edit-x A/D Reload Pct
    The AutoDual Reload Percent value has been edited from location x.
    Edit-x A/D Unload Dly
    The value has been edited from location x.
    Edit-x A/D Unload Pt
    The AutoDual Unload Point value has been edited from location x.
    Edit-x AHS Pressure
    The Auto Hot Start Pressure value has been edited from location x.
    Edit-x Auto Stop Time
    The Auto Stop Timer value has been edited from location x.
    Edit-x BV Position
    The Bypass Valve Position value has been edited while in Manual from location x.
    Edit-x BV-PID D
    The Bypass Valve Pressure PID Derivative value has been edited from location x.
    Edit-x BV-PID It
    The Bypass Valve Pressure PID Integral Time value has been edited from location x.
    Edit-x BV-PID Pb
    The Bypass Valve Pressure PID Proportional Band value has been edited from location x.
    Edit-x Coasting Timer
    The Coasting Timer value has been edited from location x.
    Edit-x CT Ratio
    The CT Ratio value has been edited from location x.
    Edit-x Day
    The Day value for the Date field has been edited from location x.
    Edit-x IV Position
    The Inlet Valve Position value when in Manual has been edited from location x.
    Edit-x IV Unload Pos
    The Inlet Valve Unload Position value has been edited from location x.
    Edit-x IV-PID D
    The Inlet Valve Pressure PID Derivative value has been edited from location x.
    Edit-x IV-PID It
    The Inlet Valve Pressure PID Integral Time value has been edited from location x.
    Edit-x IV-PID Pb
    The Inlet Valve Pressure PID Proportional Band value has been edited from location x.
    Edit-x MaxLoad SP
    The MaxLoad Setpoint value has been edited from location x.
    Edit-x MaxLoad-PID D
    The Inlet Valve MaxLoad PID Derivative value has been edited from location x.
    Edit-x MaxLoad-PID It
    The Inlet Valve MaxLoad PID Integral Time value has been edited from location x.
    Edit-x MaxLoad-PID Pb
    The Inlet Valve MaxLoad PID Proportional Band value has been edited from location x.
    Edit-x MinLoad Index
    The MinLoad Surge Index Increment value has been edited from location x.
    Edit-x MinLoad SP
    The MinLoad Setpoint value has been edited from location x.
    Edit-x MinLoad-PID D
    The Bypass Valve Pressure PID Derivative value has been edited from location x.
    Edit-x MinLoad-PID It
    The Bypass Valve Pressure PID Integral Time value has been edited from location x.
    Edit-x MinLoad-PID Pb
    The Bypass Valve Pressure PID Proportional Band value has been edited from location x.
    Edit-x Month
    The Month value for the Date field has been edited from location x.
    Edit-x PSP Ramp Rate
    The Pressure Setpoint Ramp Rate value has been edited from location x.
    Edit-x Process SP
    The Process Set Point value has been edited from location x.
    Edit-x Sensitivity
    The Surge Sensitivity value has been edited from location x.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    CMC TECHNICAL REFERENCE MANUAL
    Edit-x Starting Timer
    The Starting Timer value has been edited from location x.
    Edit-x Sys Press SP
    The System Pressure Setpoint value has been edited from location x.
    Edit-x Time
    The Time value has been edited from location x.
    Edit-x Waiting Timer
    The Wait Timer has be edited from location x.
    Edit-x Year
    The Year value for the Date field has been edited from location x.
    E-Stop pressed
    Emergency Stop push button has been pressed.
    Fail to Roll
    Did not achieve minimum slow roll speed in allotted time
    Illegal Rotation
    Unexpected rotation from driver
    Load (Location)
    A Load command has been issued from network communications.
    Loss of Motor Current
    Motor current feedback was lost while running.
    MinLoad Clamped
    The MinLoad Control or User Setpoint value has been limited to the MaxLoad Setpoint value.
    MinLoad Incremented
    The MinLoad Control Setpoint value has been incremented as a result of surge.
    MinLoad Reset
    The MinLoad Control Setpoint value has been reset to the MinLoad User Setpoint value.
    Modulate Mode Enabled
    The Modulate Mode has been enabled.
    Power Down
    The Base Control Module (BCM) was de-energized.
    Power Up
    The Base Control Module (BCM) was energized.
    Reset (Location)
    A Reset command has been issued from Location.
    Start (Location)
    A Start command has been issued from Location.
    Starter Failure
    Starter feedback was not received after a Start command was issued.
    Starter Fault-Closed
    Motor stopped but feedback present for 2 seconds
    Starting Fail
    Driver feedback was not received after a Start command was issued.
    Stop (Location)
    A Stop command has been issued from Location.
    Surge
    The controller has detected a Surge.
    Surge Unload Alarm
    The alarm condition when the compressor has unloaded as a result of multiple surges.
    TTV Switch Fault
    Trip Limit Switch Stuck
    Unload (Location)
    An Unload command has been issued from Location.
    NOTE 1: “Location” is replaced by “Comm” for communications network, “Local” for local compressor display and “Remote” for
    hardwired remote communications.
    NOTE 2: “x” is replaced by “C” for edits from a communication network and “L” for edits from the local display.
    NOTE 3: All Analog Inputs that have alarm and trip sepoints get edit local, edit communications, alarm and trip event
    messages.
    NOTE 4: All Discrete Inputs for Alarm or Trip get alarm and trip event messages.
    This next page of the INFO Folder shows the hour meters and number of starts. Power On
    Hours is the time that the panel
    INFO
    SETTINGS
    power has been on. The Running
    SYSTEM
    Hours are the amount of time that
    Power On Hours
    12338
    the compressor has been
    Running Hours
    11445
    Loaded Hours
    11223
    operating between all start and
    Number of Starts
    35
    stop sequence. The Loaded
    Hours is the amount of time that
    the compressor has been running
    BCM Ver: 3.00
    and not running unloaded. It can
    also be defined as the number of
    Load Selected
    Remote
    3/6
    hours that the inlet valve is not in
    the Inlet Unload Position. The
    Info Folder – Page 3: Hour Meters and Version
    Number of (Compressor) Starts is
    self-explanatory.
    Loaded
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    33
    34
    CMC TECHNICAL REFERENCE MANUAL
    NOTE
    Most electric motors are only rated for two cold starts or one hot start per hour. It is
    the operator’s responsibility not to exceed the electric motor’s limitation. The control
    system allows the compressor to be started when the compressor is ready, not the
    motor.
    The last item on this page is the Base Control Module Version number. This will be used by
    field personnel for quick reference to determine if newer software is available.
    This page of the INFO folder
    shows the phone number to call for
    parts or service. This is the
    number of the local Ingersoll-Rand
    representative. The number can be
    changed only by use of Service
    Tool.
    INFO
    SYSTEM
    SETTINGS
    For parts or service contact your
    local Ingersoll-Rand representative
    at the following number:
    39 02 950 56499
    Trip
    Remote
    Ready
    4/6
    Info Folder – Page 4: Phone Number
    This page provides a list of
    consumable parts found on the
    compressor package. These parts
    may also be located in the
    compressor bill of materials. In the
    event of a discrepancy, the
    compressor’s bill of materials always
    takes precedence over this page. In
    the event that the part numbers are
    not available, such as retrofitting the
    CMC on a competitive machine, this
    screen may not be visible.
    INFO
    SYSTEM
    R E P
    Part No.
    12345678
    12345678
    12345678
    12345678
    12345678
    12345678
    SETTINGS
    L A C E M E N T
    P A R T S
    Description
    Inlet Filter Element Primary
    Inlet Filter Element Secondary
    Oil Filter
    Demister Element
    Lubricant, 55 gallon drum
    Lubricant, 5 gallons
    Ready
    Trip
    Remote
    5/6
    Info Folder – Page 5: Replacement Parts
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    35
    CMC TECHNICAL REFERENCE MANUAL
    Basic operator instructions are provided on the Routine Start/Stop and Maintenance pages.
    Pressing the Enter key to initiate Scroll Mode allows access to the entire instructions.
    Scroll Mode is indicated by the reverse
    video of a slide bar. Each Down Arrow
    INFO
    SETTINGS
    SYSTEM
    press displays the next eight lines of
    R O U T I N E
    S T A R T / S T O P
    instructions. An Up Arrow press will
    Prior to starting, the operator should
    display the previous eight lines of
    become familiar with the operation of
    the main driver. Refer to the driver
    instructions. The slide bar on the page
    manufacturer's instructions in the
    indicates current location within the text.
    Operation Manual. The operator should
    If a Trip occurs while on this page, the
    also be familiar with all the accessory
    system will send the display to the event
    and optional equipment contained on the
    log page.
    Trip
    Ready
    Remote
    6/6
    Info Folder – Page 6: Operator Instructions
    SETTINGS Folder
    The SETTINGS folder is used for compressor setup. In this folder, the User will enter
    performance and control operating parameters, analog health monitoring settings for Alarm
    and Trip conditions, control mode selection, setpoint changes, password, and user interface
    language. This folder is the primary location for editing setpoints.
    The Password is used for determining
    whether Setpoint Changes can be
    made. The Password takes four
    numbers. If the Password is entered
    properly, Changes will be enabled (a
    check will be in the box); otherwise,
    they are disabled. This enabling and
    disabling applies to all changeable
    setpoints except, Pressure Setpoint,
    Throttle Limit, language selection and
    the Password, these items are always
    modifiable.
    SYSTEM
    INFO
    SETTINGS
    Password
    * * *
    Setpoint Changes Enabled
    Language and Units
    English
    degF mils amps psi
    English
    degC mils amps kg/cm2
    Date, yyyy/mm/dd
    Time, hh:mm:ss
    Loaded
    *
    1999/08/31
    12:30:00
    Load Selected
    Remote
    1/6
    Settings Folder - Page 1: Password, Language,
    Each control system is shipped with
    Time and Date
    two languages and units of measure
    combinations. The first set is for the English language, pressures in units of PSIG,
    temperatures in units of degrees F and vibrations in units of mils. The other set will be
    localized for the customer. The default alternate language is English with Metric units.
    Language support will be provided for those listed in the Technical Specification located at
    the end of the manual. Others will be available as required and translations can be
    obtained. This system has the ability for any language because of the graphics display.
    Asian character support will require additional screens because these characters require
    four times the number of pixels. There are no limitations on the units of measure. Each
    analog input has its own scaling factor and offset.
    The Date is set with three separate values (1) Year, including century (2) Month and (3)
    Day. The Time is also set with three values (1) Hour, (2) Minutes and (3) Seconds.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
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    CMC TECHNICAL REFERENCE MANUAL
    Settings Folder Page 1 Edit Parameters Table
    Variable
    Units
    Minimum
    Value
    Maximum
    Value
    Step
    Size
    1
    Password Digit
    dimensionless
    0
    9
    Date (Year)
    years
    1990
    2089
    1
    Date (Month)
    months
    1
    12
    1
    Date (Day)
    days
    1
    31
    1
    Time (Hour)
    hours
    0
    23
    1
    Time (Minute)
    minutes
    0
    59
    1
    Time (Second)
    seconds
    0
    59
    1
    The Anti-surge Settings and Driver Over-Load Protection Page has all of the settings for
    controlling and detecting surge conditions and protecting the main driver from over load
    conditions.
    The MaxLoad (HLL) setpoint
    prevents the compressor driver
    SYSTEM
    INFO
    from overloading. MinLoad User
    MaxLoad (HLL), amps
    400.0
    Setpoint (TL) is the value used to
    MinLoad
    determine what the initial (before
    User Setpoint (TL), amps
    100.0
    Control Setpoint, amps
    100.0
    indexing) motor current value will
    Surge Index Increment, amps
    1.0
    be when constant pressure control
    operation switches from the inlet
    Surge Absorber Enabled
    valve to the bypass valve.
    Surge Sensitivity
    9.0
    MinLoad Control Setpoint is the
    Load Selected
    Remote
    2/6
    actual value used to determine
    when the bypass valve begins
    Settings Folder - Page 2: Anti-Surge and Driver
    constant pressure control in lieu of
    Over-Load Protection
    the inlet valve. This value equals
    the MinLoad User Setpoint plus the
    number of surges times the index increment value. MinLoad Surge Index Increment is the
    value that the Control Setpoint is indexed after a surge has been detected. If the value for
    Surge Index Increment is equal to zero, Surge Indexing is disabled.
    SETTINGS
    Loaded
    To reset the MinLoad Control Setpoint to the MinLoad User Setpoint, hold the reset key for
    at least five seconds. The indication that it has been reset will be in the event log. The
    event message “MinLoad Reset” will be displayed. Another indication is when the MinLoad
    User Setpoint value equals the MinLoad Control Setpoint value.
    The Surge Absorber Enabled checkbox allows the user to turn off or on the Surge Absorber
    feature. When disabled, the compressor will Unload on any surge condition.
    The Surge Sensitivity setting has a range from zero (0.0) to ten point nine (10.9) where one
    is not sensitive (a “soft” surge condition could exist without being identified) and ten is very
    sensitive (a “soft” surge condition would be identified). We ship the machine with a default
    value of nine (9). This setting will pick up most surge conditions.
    22204796 Rev. B, Version 3.10
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    CMC TECHNICAL REFERENCE MANUAL
    Settings Folder Page 2 Edit Parameters Table
    Variable
    Units
    Minimum
    Value
    Maximum
    Value
    Step
    Size
    MaxLoad (HLL)
    amps
    0.0
    9999.9
    0.1
    MinLoad User Setpoint (TL)
    amps
    0.0
    100.0
    0.1
    MinLoad Surge Index Increment
    amps
    0.0
    9999.9
    0.1
    Surge Sensitivity
    dimensionless
    0.0
    10.9
    0.1
    NOTE
    MinLoad Control Setpoint is the motor amperage value used to determine when the
    bypass valve opens. MinLoad Control Setpoint will always be equal to or greater than
    the Throttle Limit value.
    CAUTION
    The MaxLoad (HLL) value should not exceed the value determined in the
    section titled Setting MaxLoad. Failure to set this properly could result in damage to
    the motor.
    CAUTION
    When Surge Indexing is enabled and the compressor surges several times,
    the compressor will begin bypassing air sooner than when Surge Indexing is
    disabled. You should periodically reset the MinLoad Control Setpoint to prevent
    excessive air bypass.
    CAUTION
    Repeated surging can cause damage to the compressor; therefore, use
    caution when desensitizing the Surge Sensitivity setting.
    22204796 Rev. B, Version 3.10
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    38
    CMC TECHNICAL REFERENCE MANUAL
    The Control Parameters Page is
    used for matching the control
    SETTINGS
    SYSTEM
    INFO
    system to the local application.
    PB
    IT
    D
    The Proportional Band (PB),
    rep/sec
    sec
    Integral Time (IT) and Derivative
    Inlet Valve
    (D) settings are provided for
    Pressure
    10.0
    0.50
    0.00
    both the inlet valve and bypass
    MinLoad (TL)
    25.00
    0.50
    0.00
    MaxLoad (HLL)
    99.99
    0.50
    0.00
    valves. This gives the controller
    Bypass Valve
    precise control for modeling the
    Pressure
    10.0
    0.50
    0.00
    air system over the entire
    Load Selected
    operating range of the
    Remote
    3/6
    compressor. With this release,
    the Derivative constant has
    Settings Folder - Page 3: Control Parameters
    (PID Settings)
    been added to give even more
    capability to match the control
    system to the air system. However, we recommend that this value remain at zero unless
    you have full understanding of how this parameter works.
    Loaded
    Settings Folder Page 3 Edit Parameters Table
    Variable
    Minimum
    Value
    Units
    Maximum
    Value
    Step
    Size
    Each PB (Proportional Band)
    dimensionless
    0.0
    99.99
    0.1
    Each It (Integral Band)
    repeats/second
    0.0
    99.99
    0.1
    Each D (Derivative Band)
    seconds
    0.0
    99.99
    0.1
    CAUTION
    Setting the Derivative parameter to a value other than zero for any of the PID
    settings may cause the valve output to change rapidly. Please change this value with
    caution.
    The Control Mode Selection Page
    allows the User to select between
    the two standard control modes,
    Modulate and Autodual. This
    selection process is performed
    with the radio button selector. To
    change the selection, press the
    Up or Down arrow key.
    Reload Percent, Unload Point
    and Unload Delay Time are all
    setpoints for Autodual control.
    SYSTEM
    INFO
    SETTINGS
    Control Mode
    Manual
    Modulate
    Autodual
    Reload Pressure, % of Setpoint
    Unload Point, BV % Open
    Unload Delay Timer, seconds
    Loaded
    98
    1
    1
    Load Selected
    Remote
    4/6
    Settings Folder - Page 4: Control Mode Selection
    Checking the Manual checkbox enables manual valve control. In this mode, the inlet valve
    may be stroked when the compressor is not running, and the bypass valve can be stroked
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    39
    CMC TECHNICAL REFERENCE MANUAL
    at any time. If a surge condition occurs while manually controlling these valves, the CMC
    will automatically take over the valves.
    Settings Folder Page 4 Edit Parameters Table
    Variable
    Units
    Minimum
    Value
    Maximum
    Value
    Step
    Size
    1
    Autodual Reload Pressure
    % of Setpoint
    0
    99
    Autodual Unload Point
    BV % Open
    1
    99
    1
    Autodual Unload Delay Timer
    seconds
    0
    999
    1
    CAUTION
    Manual should only be used for compressor setup.
    Starting Timer is the length of time prior to enabling the loading of the compressor.
    Typically, this time includes the starter transition time (Y-D time) and the prelube pump
    shutdown. When this timer expires, the prelube pump will turn off and the compressor is
    enabled for loading.
    Coasting Timer is the length of time that it takes for the driver to stop rotating.
    SYSTEM
    INFO
    SETTINGS
    Starting Timer, seconds
    Coasting Timer, seconds
    CT Ratio
    Motor Failure Trip Enable
    Inlet Valve Unload Position, %
    Setpoint Ramp Rate, pressure/scan
    Loaded
    20
    240
    60
    15
    5.0
    Load Selected
    Remote
    5/6
    Settings Folder - Page 5: Miscellaneous
    CT Ratio is the ratio of the current
    transformer primary to the
    secondary; i.e., if the CT primary
    winding is 300 and the secondary
    winding is 5, then the CT Ratio is
    60.
    When checked, Motor Failure Trip
    Enable tests that the zero_amp
    motor_current variable has been
    reached after a start command has
    been initiated and that motor
    current is not lost while the
    compressor is running. Uncheck
    this box for dry run conditions.
    The Inlet Unload Position is the position of the inlet valve when in the unload state.
    Setpoint Ramp Rate is used to prevent system pressure overshoot during compressor
    loading.
    Additional settings will be added to this page for “special” features.
    22204796 Rev. B, Version 3.10
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    Date of Issue: March 24, 2003
    40
    CMC TECHNICAL REFERENCE MANUAL
    Settings Folder Page 5 Edit Parameters Table
    Variable
    Minimum
    Value
    Units
    Maximum
    Value
    Step
    Size
    Starting Timer
    seconds
    5
    60
    1
    Coasting Timer
    seconds
    60
    9999
    1
    CT Ratio
    dimensionless
    60
    9999
    1
    Inlet Valve Unload Position
    percent
    0
    100
    1
    Setpoint Ramp Rate
    pressure/scan
    0
    999.9
    0.1
    WARNING
    Failure to set the Coast Timer for a period greater than or equal to the actual
    coasting time can result in compressor damage.
    The Alarm and Trip Settings Page
    provides the means for changing
    the analog health monitoring
    values. The number of inputs
    varies depending upon the number
    of compression stages and
    optional inputs. Additional pages
    will be added as needed after this
    page. All line items are changeable
    for the Alarm and Trip setpoints.
    SYSTEM
    INFO
    SETTINGS
    Stage 1 Temperature
    Stage 1 Vibration
    Stage 2 Temperature
    Stage 2 Vibration
    Oil Pressure
    High Oil Temperature
    Low Oil Temperature
    Loaded
    Alarm
    120
    0.80
    120
    0.75
    18
    120
    100
    Trip
    125
    1.00
    125
    0.95
    16
    125
    95
    Load Selected
    Remote
    6/6
    Settings Folder - Page 6: Alarm and Trip
    WARNING
    Setting Trip values outside the range specified on the drawings can result in
    compressor damage.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    41
    CMC TECHNICAL REFERENCE MANUAL
    General Sequence of Operation
    To start and load a
    compressor follow
    steps 1, 2, 3 and 4
    CENTAC  Microcontroller
    SYSTEM
    System
    Pressure
    1
    Press
    Reset
    Pressure
    Setpoint
    Motor
    Current
    2 Look for
    INFO
    SETTINGS
    105.3
    105.0
    173.4
    Inlet
    Valve
    Bypass
    Valve
    22JUL96
    Loaded
    "Ready"
    95
    0
    12:00:00
    Load Selected
    Remote
    1/2
    3 Press Start
    4 Press Load
    Press Unload,
    5 wait 20 seconds
    To unload and stop
    a compressor follow
    steps 5 and 6
    6 Press Stop
    Compressor Operating States
    Motor
    Current
    Coasting
    Unloaded
    Unloading
    MaxLoad Setpoint Amps
    Motor Full Load Amps
    Load
    No
    Stops or
    Trips
    MinLoad Setpoint Amps
    Any
    Stops or
    Trips
    Start
    Unloaded Amps
    Zero Amp Offset
    0
    Power
    On
    MaxLoad
    Loaded
    Full Load
    Loaded
    Unload
    Motor Full Load Amps Plus Service Factor
    amps, %
    100
    MinLoad
    Loading
    Unloaded
    Starting
    Ready
    Not Ready
    Waiting
    for Motor Driven Packages
    Stopped
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Rotating
    42
    CMC TECHNICAL REFERENCE MANUAL
    Indicator, Switch and Light Layout
    In addition to the CMC OUI there may be a variety of indicators, switches, and lights
    mounted on the control panel door. In conjunction with the CMC OUI these devices make
    up the User Interface for the CMC. A typical device layout consists of the following lights,
    push buttons, and selector switches.
    Lights
    The lights provided are the green CONTROL POWER ON light, which is integral to the
    CONTROL POWER OFF/ON switch, the amber PRELUBE PUMP RUNNING light and the
    red TROUBLE INDICATION light.
    Push Buttons
    The red EMERGENCY STOP push button stops the compressor any time that it is pressed.
    This push button is used to initiate a stop in the case of an emergency.
    Switches
    The CONTROL POWER OFF/ON selector switch turns the panel power on or off
    CMC Tuning Procedures
    When commissioning a new compressor, troubleshooting an existing compressor, or tuning
    a system, the following procedures may be required. The procedures are performed, and
    any changes required are made through the CMC OUI. For instructions on how to use the
    OUI refer to the section titled User Interface. The following figure will be referenced in the
    procedures.
    PT
    1
    PT
    2
    Bypass
    Valve
    Pneumatic Tubing
    Check
    Valve
    4-20 mA
    Base
    Control
    Module
    CT
    Block
    Valve
    Starter
    Motor
    Compressor
    Plant Air System
    4-20 mA
    Inlet
    Valve
    Inlet Filter
    Figure 18: Plant Air System
    Setting MaxLoad
    The MaxLoad Setpoint keeps the motor within the allowable current range. To determine
    the value for MaxLoad, an Adjusted Service Factor (ASF) is multiplied by the motor full load
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
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    43
    CMC TECHNICAL REFERENCE MANUAL
    amps (FLA). The (ASF) is found by obtaining the motor service factor from the motor
    nameplate and selecting the adjustment factor from the table below. The motor full load
    amps is found on the motor nameplate.
    Motor Service Factor
    1.15
    1.25
    Example:
    FLA:
    Adjusted service factor:
    MaxLoad:
    Adjusted Service Factor
    1.05
    1.10
    MaxLoad = FLA X ASF
    134 Amps
    1.05
    140
    Setting MinLoad
    MinLoad establishes the minimum flow through the machine when loaded; it is the
    maximum point of inlet valve throttling. If system demand is below this throttle point, the
    compressor must bypass air or unload. If flow were allowed to go below MinLoad, the
    machine would eventually cross the surge line and surge. By stopping inlet valve throttling
    at MinLoad the machine is kept out of surge. To find the MinLoad setting, the machine is
    run into the surge line, and the value of load (amps, kilowatts, SCFM) at surge is recorded.
    The recorded value is then incremented by five percent and set as the value for MinLoad.
    1. Before continuing this procedure, verify the following:
    a) The inlet and bypass control valves have been calibrated.
    b) The machine is running unloaded.
    c) The block valve at the inlet to the plant air system (Figure 18) is closed.
    d) The pressure setpoint is set to the pressure at which the machine is going to
    operate.
    2. Set initial MinLoad estimates.
    a) In the Settings Folder, select the Edit Data cell for MinLoad.
    b) Increment or decrement the value to achieve a value of approximately 95% of full
    load amps.
    3. Preset the manual bypass valve position to 100.
    a) On the OUI select the Settings Folder and enable manual valve control by
    highlighting the manual check box.
    NOTE
    When Manual is enabled, both control valves can be positioned while stopped, while
    only the Bypass Valve can be positioned when Loaded.
    b) Switch to the System Folder Page 1 and press the Enter Key to enable edit mode.
    c) Use the horizontal navigation keys to select the bypass valve.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
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    44
    CMC TECHNICAL REFERENCE MANUAL
    d) Increment the value to position the valve to 100 percent.
    4. Load the compressor by pressing the Load Key.
    5. Find the throttled surge point.
    a) Slowly decrement the bypass valve position until the last stage discharge pressure
    equals the pressure setpoint.
    b) Allow the system to stabilize at MinLoad. It the system does not stay at MinLoad,
    slightly decrement the valve position to force the machine to throttle to MinLoad.
    c) Decrement (MinLoad) 2%.
    d) Verify the last stage pressure equals the pressure setpoint and adjust the bypass
    valve position if necessary.
    e) Repeat c) and d) until the compressor surges.
    6. Increase MinLoad by five percent.
    7. Exit MinLoad editing by pressing the Enter Key.
    8. Unload the machine.
    9. Disable manual valve control by unchecking the manual check box.
    Setting MinLoad Surge Index Increment
    When Surge Indexing is enabled (MinLoad Surge Index Increment is greater than zero), the
    Index Increment value is the amount added to the MinLoad Control Setpoint upon a surge.
    The MinLoad Control Setpoint will stop being incremented when and if the value reaches
    MaxLoad.
    Setting Surge Sensitivity
    The Surge Sensitivity setting should be set sensitive enough to detect a surge, yet not
    trigger on spurious noise in the system. To set the surge sensor the machine is forced to
    surge by running the machine at MinLoad and the MinLoad setpoint is dropped until the
    machine audibly surges. The process is repeated until the correct setting is found.
    1. Before continuing this procedure, verify the following:
    a) The plant can tolerate a pressure disturbance when the machine surges.
    b) Surge Indexing (by placing MinLoad Surge Index Increment to zero) is disabled.
    c) Surge Absorber is disabled.
    d) The pressure setpoint is set to the pressure at which the machine is going to
    operate.
    e) The machine is running unloaded.
    2. Set the initial Surge Sensitivity setting to 9.
    a) In the Settings Folder, select the Edit Data cell for Surge Sensitivity.
    b) Increment or decrement the value to achieve a setting of 9.
    3. Press the Load Key.
    22204796 Rev. B, Version 3.10
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    CMC TECHNICAL REFERENCE MANUAL
    4. Run the compressor at MinLoad and system pressure setpoint pressure. The
    machine can be forced to MinLoad and to maintain system pressure setpoint by either.
    a) Running the plant at a higher pressure than pressure setpoint.
    b) Decreasing load in the plant.
    c) Verify the compressor is at pressure by observing the last stage pressure on
    Page 2 of the Settings Folder.
    5. Find the throttled surge point.
    a) Select the MinLoad cell in the Settings Folder and slowly decrement the value until
    the machine surges. Typically the machine will make a puffing or popping noise
    upon surge, this is your indication surge has occurred.
    6. Press the Unload Key.
    7. Determine if Surge was recorded.
    a) Inspect the Status Bar. If the message Surge Unload is displayed surge was
    recorded, if the message is not displayed surge was not recorded.
    8. Check the Surge Sensitivity setting.
    a) If the surge was recorded, the setting may be correct or the Surge Sensor may be
    too sensitive, skip to the too sensitive step, which follows.
    b) If the surge was not recorded, the setting is not sensitive enough, skip to the not
    sensitive enough step, which follows.
    9. Surge Sensor too sensitive.
    a) Select the Surge Sensitivity Setting in the Settings Folder.
    b) Decrease the value for Surge Sensitivity by 0.1.
    c) Press the Reset Key.
    d) Skip to step 11.
    10. Surge Sensor not sensitive enough.
    a) Select the Surge Sensitivity Setting in the Settings Folder.
    b) Increase the value for Surge Sensitivity by 0.1.
    c) Press the Reset Key.
    11. Repeat the procedure until the Surge Sensitivity setting is found which just catches a
    surge but does not miss a surge.
    a) Return to step 3.
    12. Restore MinLoad value.
    Tuning Stability
    The CMC controls stability with four Proportion Integral Derivative (PID) control loops.
    When the machine is running above the MinLoad point and below the MaxLoad point,
    pressure is regulated with the Inlet Valve Pressure control loop. When the machine is
    running at the MinLoad point, pressure is regulated with the Bypass Valve Pressure control
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    45
    46
    CMC TECHNICAL REFERENCE MANUAL
    loop and motor current is regulated with the Inlet Valve MinLoad control loop. When the
    machine is running at MaxLoad motor current is regulated with the Inlet Valve MaxLoad
    control loop. For each PID loop, Proportional, Integral and Derivative parameters are used
    to stabilize the system. For a definition of the parameters and their effect on stability, refer
    to the section titled “How does Constant Pressure Modulation Work.” The proportional and
    integral terms are labeled by their respective loops, Inlet Valve, Bypass Valve, MinLoad,
    and MaxLoad.
    Calibrating the Control Valves
    The purpose of this procedure is to position the inlet and bypass valves by opening and
    closing each valve from the CMC analog outputs. The valves should be adjusted to
    physically correspond with the valve positions displayed on the OUI.
    1.
    Stop the compressor.
    NOTE
    Performing this procedure while the compressor is operating may cause serious
    damage.
    2.
    On the OUI enable Setpoint changes by entering the password on the Settings Folder.
    3.
    Verify the OUI status bar displays “Ready” or “Not Ready”.
    4.
    On the OUI select the Settings Folder and enable manual valve control by highlighting
    the manual check box.
    NOTE
    When Manual is enabled, both control valves can be positioned while stopped, while
    only the Bypass Valve can be positioned when Loaded.
    5.
    Switch to the System Folder Page 1 and press the Enter Key to enable edit mode.
    6.
    Use the horizontal navigation keys to select the valve requiring positioning.
    7.
    Use the vertical arrows to increment and decrement the valve position sent to the
    valve.
    NOTE
    For the Inlet and Bypass Valves, the displayed position corresponds to percent open.
    8.
    Disable manual valve control by blanking the manual check box.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    47
    CMC TECHNICAL REFERENCE MANUAL
    Autodual Control Settings
    For a detailed definition of the Autodual control mode refer to the section titled “Control
    Methodology”. The procedure for tuning Autodual requires the setting of the following
    variables:
    Unload Point (Bypass Valve % Open)
    The Bypass Valve Unload Point is selected to correspond to the check valve closing as
    shown in Figure 18, since at this point the machine is not supplying the system. This
    position is found by running the machine at MinLoad and monitoring the System and
    Discharge pressures. When the System pressure is 5% of setpoint greater than the last
    stage pressure as shown in the System Folder, the check valve is assumed to be closed.
    Example: Given the following conditions the Unload Point would be set at 35.
    Variable
    Pressure Setpoint
    PT1 (system pressure)
    PT2 (last stage pressure)
    Bypass Valve Position
    Assumed check valve position
    Case 1
    100
    100
    100
    13
    Open
    Case 2
    100
    100
    94
    35
    Closed
    1. Run the machine at MinLoad by elevating the system pressure no more than 3% or
    decrease the pressure setpoint no more than 3%.
    2. Monitor the difference between the Discharge and System Pressures by using the
    System Folder Pages 1 and 2.
    3. When the Discharge Pressure is approximately 95% of setpoint, record the Bypass
    Valve Position.
    4. Enter the recorded Bypass Valve Position as the Unload Point.
    Unload Delay Time (seconds)
    The Unload Delay Timer should be set to prevent unloading during short excursions
    through the Unload Point. Typically, when the check valve closes, system demand requires
    the check valve to open again soon thereafter due to the demand being on the verge of
    requiring the compressor. If the compressor had unloaded when the check valve first
    closed, a reload would be immediately required and the machine would go through the
    automatic unload/load cycle until demand was consistently low enough to keep the check
    valve closed. For this reason, the timer is used to inhibit Unload until demand has
    consistently remained low. This value should be set according to the customer’s
    observation experience as to how often system demand changes impact the reloading of
    the compressor.
    Reload Percent
    The Reload Percent determines the System Pressure at which the machine will
    automatically load into the system. This value should be set according to the customer’s
    minimum acceptable system pressure.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    48
    CMC TECHNICAL REFERENCE MANUAL
    Setting the Start Time
    The Start Time is set to the transition time of a built-in reduced voltage starter or the
    acceleration time of a customer supplied starter. This procedure requires the Inlet Unload
    Position to have been set.
    CAUTION
    Damage to the starter contacts could result if starter transition occurs before
    the compressor is up to full speed.
    1.
    Initially set the Start Time to 25 Seconds.
    2.
    Stop the compressor. Allow compressor to coast to a stop.
    3.
    On the OUI record the time and press the start button.
    4.
    Wait for the compressor to stop accelerating and again record the time.
    5.
    Calculate the difference between the two values and enter as the Start Time.
    Setting the CT Ratio
    Locate the CT and find the rating, which is typically printed, on the side of the CT. Divide
    the primary by the secondary and enter the value as the CT Ratio.
    Example: CT is printed with 600:5, the value entered is 120.
    Inlet Unload Position
    The purpose of this variable is to set the inlet valve position when the machine is running
    unloaded. For a description of the Unloaded state refer to the section titled “Unload”.
    1.
    If the inlet valve is a butterfly type, enter an initial value for Inlet Unload Position of 15. If
    the inlet valve is a inlet guide vane type, enter an initial value for Inlet Unload Position of
    5.
    2.
    Start the machine. If during startup the motor trips on overload, draws what is
    considered excessive amperage or sounds labored, stop the machine and decrease the
    Unload Position by 2 and restart the machine.
    3.
    Run the machine in the Unloaded state and monitor the first stage pressure.
    4.
    Adjust the Unload Position to achieve 1 PSIG on the first stage discharge, or until a
    positive pressure is felt at the first stage condensate trap bypass.
    5.
    If the inlet air temperature is relatively cold, increase the setting 2%, this will
    accommodate hot day operation.
    Setting Set Point Ramp Rate
    Setpoint ramp rate determines the rate at which the machine transitions from unloaded to
    loaded. The setting should be set as high as possible without creating excessive overshoot
    when the machine enters the system.
    1.
    Verify the machine is unloaded by the “Unloaded” message in the OUI Status Bar.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    CMC TECHNICAL REFERENCE MANUAL
    2.
    3.
    4.
    5.
    Determine overshoot.
    a)
    Load the machine.
    b)
    Monitor the pressure overshoot.
    If overshoot is excessive.
    a)
    Decrease the Setpoint Ramp Rate.
    b)
    Repeat step 2.
    If overshoot is satisfactory and time to load is excessive.
    a)
    Increase the Setpoint Ramp Rate.
    b)
    Repeat step 2.
    If overshoot is satisfactory and time to load is satisfactory the Setpoint Ramp Rate is
    correct.
    Alarm and Trip Settings
    The values for vibration, temperature, pressure etc. alarm and trip setpoints are located on the
    electrical schematic. These values determine when the controller will indicate an alarm or trip
    condition.
    WARNING
    Setting Trip values outside the range specified on the drawings can result in
    compressor damage.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    49
    50
    CMC TECHNICAL REFERENCE MANUAL
    Troubleshooting
    The following procedures provide direction on troubleshooting the CMC System, control
    panel, and associated instrumentation. Faults are either Event Logged, which means the
    fault is displayed in the INFO Folder on the OUI, or Non-Event Logged. The distinction
    helps to expedite the troubleshooting process.
    When a control system fault is suspected, the following diagram is used to categorize the
    fault. The section following the diagram breaks each category down into specific items,
    which can cause a particular fault.
    A CONTROL
    SYSTEM FAULT IS
    SUSPECTED
    THE FAULT IS LOGGED IN
    THE EVENT LOG.
    COMPRESSOR RELATED
    I/O FAULT
    Event correctly indicates a problem.
    Temperature, pressure, load, valve, etc.
    readings incorrect.
    (Refer to the compressor operating manual)
    THE FAULT IS NOT LOGGED IN
    THE EVENT LOG
    CONTROL PROBLEMS
    Compressor fails to Load, fails to trip, fails to
    start, surging, etc.
    (Refer to the CMC Tuning Procedures section)
    (Refer to the Input/Output (I/O) System)
    STABILITY PROBLEMS
    CONTROLLER PROBLEMS
    Inlet valve, bypass valve, or control variables
    (mass flow, system pressure, Kw, amps) are
    unstable.
    OUI failed, BCM failed, UCM failed,
    Communications failed.
    (Refer to Controller Problems Section)
    (Refer to the CMC Tuning Procedures Section)
    Figure 19: Troubleshooting Tree
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    51
    CMC TECHNICAL REFERENCE MANUAL
    Troubleshooting Example
    The following example will serve as a guide to follow when troubleshooting specific
    problems.
    Problem Indication:
    Plant air pressure is low and the CMC OUI is found
    as shown.
    Probable Cause Determination:
    1.
    SYSTEM
    1
    2
    3
    4
    5
    6
    7
    INFO
    SETTINGS
    Event Name
    Low Oil Pressure Trip
    Low Oil Pressure Alarm
    Reset key pressed
    Low Oil Pressure Trip
    Low Oil Pressure Alarm
    Load key pressed
    Start key pressed
    Not Ready
    Time
    Date
    09:18:44 0720
    09:18:43 0720
    09:18:34 0720
    09:08:43 0720
    08:58:23 0720
    08:24:01 0720
    08:23:12 0720
    Trip
    Remote
    2/6
    The machine Tripped on Low Oil Pressure, which means the oil pressure, was below
    the Oil Pressure Trip Value. Figure 19 leads to the assumption that the problem is
    either compressor or I/O related, because the fault is Event Logged. There are two
    most likely causes for this event.
    a) Actual oil pressure is low.
    i)
    The prelube pump is found to be running and installation of a calibrated
    pressure sensor shows the actual oil pressure to be above the Oil Pressure Trip
    Value. Therefore, the mechanical system is operating correctly.
    b) The value read by the CMC is incorrect.
    i)
    The oil pressure value displayed on Page 2 of the System Folder shows the oil
    pressure to be below the test sensor reading and erratic. Additionally, all other
    analog input readings are normal and not erratic. Therefore, the problem can be
    isolated to the oil pressure, analog input circuit.
    ii)
    The Pressure Monitoring System (PMS) troubleshooting table, found in the
    following section “The Pressure Monitoring System” identifies the probable
    cause for an erratic reading as a loose wire/terminal/connector and specifies
    Troubleshooting Procedure PMS #1 and 2 as the appropriate procedures.
    Trouble Procedure Execution:
    Step 1 of PMS #1 requires disconnecting of the pressure transducer (PT) wires at the
    terminal strip. When this step is performed, one of the connections is found to be
    intermittent. When the poor connection is corrected, the erratic reading on the OUI
    becomes solid.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    52
    CMC TECHNICAL REFERENCE MANUAL
    Input/Output (I/O) System
    Vibration Monitoring System (VMS)
    Description:
    The vibration transmitter is used to convert the proximity probe signal into a 4 -20 mA
    signal, which is monitored by the CMC. The system is based on a 5 meter total electrical
    length (vibration probe electrical length plus extension cable electrical length).
    Component specifications: (5 meter)
    Transmitter:
    •
    200 mv/mil = 0.2 volt per 0.001 in (0.0254 mm)
    •
    4 mil (0.1016 mm) scale
    •
    4-20 mA output
    Probe:
    •
    Gap setting 0.030 to 0.060 in (0.762 to 1.524 mm), see Service Hints for nominal gap
    •
    Probe gap corresponds to 6 to 12 volts VDC
    •
    Ohm value of 0.5 meter Probe is 4 ohms, +/- 0.5 ohm
    Troubleshooting:
    The following table identifies typical problems, probable causes, and appropriate
    procedures for verifying the probable cause:
    Typical Problem
    Zero OUI readout
    (when compressor is
    running)
    Erratic OUI readout
    Incorrect OUI readout
    Probable Cause
    Open circuit/cable disconnected
    Loss of power to transmitter
    Malfunctioning transmitter
    Transmitter not calibrated
    Loose wire/terminal/connector
    Any
    Troubleshooting Procedure
    VMS #2, 3, 4
    VMS #1
    VMS #2
    VMS #2
    VMS #2, 3, 4
    VMS #1, 2, 3, 4, 5
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    53
    CMC TECHNICAL REFERENCE MANUAL
    Checking Vibration Transmitter Power
    VMS #1
    1. Connect a DC voltmeter to the +
    and
    terminals
    of
    the
    transmitter.
    2. With control power on, there
    should be approximately 24
    VDC present at the terminals.
    3. If approximately 24 VDC is not
    present; see the section titled
    “Control Power System”.
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    VDC
    mA
    VAC
    Ω
    mA COM V Ω
    NOTE: Under no circumstances
    should the vibration transmitter zero
    or span be adjusted. Calibration of
    the vibration transmitter requires
    special tooling and calibration
    fixtures. Contact the factory if
    calibration is required.
    (See electrical
    schematic for point).
    Vibration
    transmitter
    Checking Vibration Circuit
    1. With control power on, check the dc
    voltage at the COM and TEST terminals
    on the transmitter. A reading of 6 to 12
    VDC should be present [this corresponds
    to a 0.030 to 0.060 inches (0.762 to
    1.524 mm)] probe gap.
    2. If less than 6 volts is present the probe
    gap may be incorrect, or a short circuit
    may exist. Check the cable connections
    and cable.
    3. If more than 12 volts is present the probe
    gap may be incorrect, or an open circuit
    may exist. Check the cable connections
    and cable.
    4. If no voltage exists, the transmitter may
    be faulty. Remove control power and
    swap connections with another
    transmitter and test.
    VMS #2
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    VDC
    mA
    VAC
    Ω
    mA COM V Ω
    Compressor casing
    Vibration transmitter
    Vibration probe
    Probe extension cable
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    54
    CMC TECHNICAL REFERENCE MANUAL
    Check the Vibration Probe, and Cable
    VMS #3
    1. Turn control power off and disconnect
    the probe extension cable from the
    transmitter.
    2. Check resistance of the extension cable
    and probe together, the reading should
    be 5.3 ohms, +/- 0.7 ohm (5 meter
    system)
    Probe connector
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    VDC
    mA
    VAC
    Ω
    Probe cable
    mA COM V Ω
    Compressor
    casing
    Connect test lead
    to outer shell.
    Connect test lead
    to inner pin.
    Probe extension
    cable
    Vibration probe
    Checking the Vibration Probe
    1. Turn control power off and disconnect
    the probe extension cable from the
    transmitter.
    2. Check resistance of the probe alone, the
    reading should be 4.0 ohms, +/- 0.5 ohm
    (0.5 meter probe)
    VMS #4
    Connect test lead
    to outer shell.
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    Probe connector
    XXXXX
    XXXXX
    VDC
    mA
    VAC
    Ω
    Probe cable
    mA COM V Ω
    Vibration probe
    Connect test lead
    to inner pin.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    55
    CMC TECHNICAL REFERENCE MANUAL
    Check the BCM
    VMS #5
    1. With control power off connect a 4-20 mA simulator at the input points of the suspected
    faulty device at connector J1, (see electrical schematic for connection points).
    2. Turn control power on and vary the signal. If the value tracks according to the table
    below, the wiring is faulty.
    3. Verify the connector at J1 is fully seated. If the value does not track correctly, the BCM
    may be faulty.
    BCM
    J2-Floating Analog Inputs, (4-20mA) Channels 1-2
    J1-Grounded Analog Inputs,
    (4-20mA) Channels 3-23
    Pin 25
    Pin 1
    4-20 mA SURCE OR
    2 WIRE SIMULATOR
    LOOP
    ON
    DIAL
    100%
    BATTERY
    CHECK
    OFF
    2 WIRE
    mA OUT
    00.0% - 100%
    00.0%
    XXXXXX
    MODEL CL-XXX
    555
    mA percent
    (from simulator)
    100%
    50%
    0%
    Conversion chart
    Mils
    (on OUI)
    4.0
    2.0
    0.0
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    mA
    (from simulator)
    20
    12
    4
    56
    CMC TECHNICAL REFERENCE MANUAL
    Temperature Monitoring System (TMS)
    Description:
    An RTD (Resistance Temperature Detector-2 Wire) with external transmitter is used by the
    CMC for temperature monitoring. An RTD resistance (ohmic value) varies with temperature.
    A transmitter for monitoring by the CMC analog input channel converts the resistance to a
    4-20 mA signal.
    Component specification:
    Probe:
    •
    100 ohm Platinum resistance at 32 °F (0°C) with Temperature Coefficient Rating (TCR)
    of 0.00385 Ohm/Ohm/Deg C
    Transmitter:
    •
    The transmitter may be mounted in the RTD connection head fitting or in the control
    panel enclosure. The transmitter is supplied 24 VDC and outputs 4-20mA over a fixed
    range of either 0 to 200°F (-17.7 to +93.3°C), or 0-500°F (-17.7 to +260°C).
    Troubleshooting:
    The following table identifies typical problems, probable causes, and appropriate
    procedures for verifying the probable cause:
    Typical Problem
    High OUI readout
    Probable Cause
    High resistance connection
    Transmitter not calibrated
    RTD failure
    Transmitter failure
    Low OUI readout
    Transmitter failure
    RTD failure
    Transmitter not calibrated
    Erratic OUI readout
    Loose terminal connection
    RTD internal wire fault
    Transmitter failure
    Incorrect OUI readout Transmitter not calibrated
    RTD or transmitter failure
    Any
    Troubleshooting
    Procedure
    TMS #4
    TMS #3
    TMS #2
    TMS #3
    TMS #3
    TMS #2
    TMS #3
    TMS #4
    TMS #2
    TMS #3
    TMS #3
    TMS #2, 3
    TMS #1, 2, 3, 4
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    57
    CMC TECHNICAL REFERENCE MANUAL
    Checking for Power to the Temperature Transmitter
    TMS #1
    1. Disconnect the wires at terminals #1 and #2 on the transmitter and connect a voltmeter
    to these wires.
    2. With control power on, there should be approximately 24 VDC present at the terminals.
    3. If approximately 24 VDC is not present, see the section titled “Control Power System”.
    BCM
    J2-Floating Analog Inputs, (4-20mA) Channels 1-2
    J1-Grounded Analog Inputs,
    (4-20mA) Channels 3-23
    Pin 25
    Pin 1
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    VDC
    XXXXX
    XXXXX
    mA
    123 4
    VAC
    Ω
    mA COM V Ω
    RTD
    Temperature transmitter
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    58
    CMC TECHNICAL REFERENCE MANUAL
    Checking for a Faulty RTD
    TMS #2
    1. Turn control power off.
    2. Check ohms versus temperature. Use an
    Ohmmeter and the following tables to
    determine if the RTD is faulty. Vary the
    temperature to the RTD and check the
    ohms around the normal operating
    range.
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    VDC
    mA
    VAC
    Ω
    mA COM V Ω
    Thermometer
    RTD
    32 DEGF
    Ice water
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    59
    CMC TECHNICAL REFERENCE MANUAL
    Degrees Fahrenheit versus Ohms value chart for 100 OHM Platinum RTD
    °F
    0
    10
    20
    30
    40
    50
    60
    70
    80
    90
    100
    110
    120
    130
    140
    150
    160
    170
    180
    190
    200
    210
    220
    230
    240
    250
    260
    270
    280
    290
    300
    310
    320
    330
    340
    350
    360
    370
    380
    390
    400
    410
    420
    430
    440
    450
    460
    470
    480
    490
    500
    0
    93.01
    95.20
    97.38
    99.56
    101.70
    103.90
    106.10
    108.20
    110.40
    112.50
    114.70
    116.80
    119.00
    121.10
    123.20
    125.40
    127.50
    129.60
    131.70
    133.90
    136.00
    138.10
    140.20
    142.30
    144.40
    146.50
    148.60
    150.70
    152.70
    154.80
    156.90
    159.00
    161.00
    163.10
    165.20
    167.20
    169.30
    171.30
    173.40
    175.40
    177.50
    179.50
    181.50
    183.60
    185.60
    187.60
    189.70
    191.70
    193.70
    195.70
    197.70
    1
    93.22
    95.42
    97.60
    99.78
    102.00
    104.10
    106.30
    108.40
    110.60
    112.70
    114.90
    117.00
    119.20
    121.30
    123.40
    125.60
    127.70
    129.80
    132.00
    134.10
    136.20
    138.30
    140.40
    142.50
    144.60
    146.70
    148.80
    150.90
    153.00
    155.00
    157.10
    159.20
    161.30
    163.30
    165.40
    167.40
    169.50
    171.50
    173.60
    175.60
    177.70
    179.70
    181.80
    183.80
    185.80
    187.80
    189.90
    191.90
    193.90
    195.90
    197.90
    2
    93.44
    95.63
    97.82
    100.00
    102.20
    104.30
    106.50
    108.70
    110.80
    113.00
    115.10
    117.30
    119.40
    121.50
    123.60
    125.80
    127.90
    130.00
    132.20
    134.30
    136.40
    138.50
    140.60
    142.70
    144.80
    146.90
    149.00
    151.10
    153.20
    155.20
    157.30
    159.40
    161.50
    163.50
    165.60
    167.60
    169.70
    171.80
    173.80
    175.80
    177.90
    179.90
    182.00
    184.00
    186.00
    188.00
    190.10
    192.10
    194.10
    196.10
    198.10
    3
    93.66
    95.85
    98.04
    100.20
    102.40
    104.60
    106.70
    108.90
    111.00
    113.20
    115.30
    117.50
    119.60
    121.70
    123.90
    126.00
    128.10
    130.30
    132.40
    134.50
    136.60
    138.70
    140.80
    142.90
    145.00
    147.10
    149.20
    151.30
    153.40
    155.40
    157.50
    159.60
    161.70
    163.70
    165.80
    167.80
    169.90
    172.00
    174.00
    176.00
    178.10
    180.10
    182.20
    184.20
    186.20
    188.20
    190.30
    192.30
    194.30
    196.30
    198.30
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    4
    93.88
    96.07
    98.26
    100.40
    102.60
    104.80
    106.90
    109.10
    111.20
    113.40
    115.50
    117.70
    119.80
    122.00
    124.10
    126.20
    128.30
    130.50
    132.60
    134.70
    136.80
    138.90
    141.00
    143.10
    145.20
    147.30
    149.40
    151.50
    153.60
    155.70
    157.70
    159.80
    161.90
    163.90
    166.00
    168.10
    170.10
    172.20
    174.20
    176.30
    178.30
    180.30
    182.40
    184.40
    186.40
    188.40
    190.50
    192.50
    194.50
    196.50
    198.50
    5
    94.10
    96.29
    98.47
    100.70
    102.80
    105.00
    107.10
    109.30
    111.50
    113.60
    115.80
    117.90
    120.00
    122.20
    124.30
    126.40
    128.60
    130.70
    132.80
    134.90
    137.00
    139.10
    141.20
    143.30
    145.40
    147.50
    149.60
    151.70
    153.80
    155.90
    157.90
    160.00
    162.10
    164.10
    166.20
    168.30
    170.30
    172.40
    174.40
    176.50
    178.50
    180.50
    182.60
    184.60
    186.60
    188.60
    190.70
    192.70
    194.70
    196.70
    198.70
    6
    94.32
    96.51
    98.69
    100.90
    103.00
    105.20
    107.40
    109.50
    111.70
    113.80
    116.00
    118.10
    120.20
    122.40
    124.50
    126.60
    128.80
    130.90
    133.00
    135.10
    137.20
    139.30
    141.40
    143.50
    145.60
    147.70
    149.80
    151.90
    154.00
    156.10
    158.10
    160.20
    162.30
    164.30
    166.40
    168.50
    170.50
    172.60
    174.60
    176.70
    178.70
    180.70
    182.80
    184.80
    186.80
    188.80
    190.90
    192.90
    194.90
    196.90
    198.90
    7
    94.54
    96.73
    98.91
    101.10
    103.30
    105.40
    107.60
    109.70
    111.90
    114.00
    116.20
    118.30
    120.50
    122.60
    124.70
    126.90
    129.00
    131.10
    133.20
    135.30
    137.40
    139.60
    141.70
    143.80
    145.90
    147.90
    150.00
    152.10
    154.20
    156.30
    158.40
    160.40
    162.50
    164.60
    166.60
    168.70
    170.70
    172.80
    174.80
    176.90
    178.90
    180.90
    183.00
    185.00
    187.00
    189.00
    191.10
    193.10
    195.10
    197.10
    199.10
    8
    94.76
    96.95
    99.13
    101.30
    103.50
    105.60
    107.80
    109.90
    112.10
    114.30
    116.40
    118.50
    120.70
    122.80
    124.90
    127.10
    129.20
    131.30
    133.40
    135.50
    137.70
    139.80
    141.90
    144.00
    146.10
    148.20
    150.20
    152.30
    154.40
    156.50
    158.60
    160.60
    162.70
    164.80
    166.80
    168.90
    170.90
    173.00
    175.00
    177.10
    179.10
    181.10
    183.20
    185.20
    187.20
    189.20
    191.30
    193.30
    195.30
    197.30
    199.30
    9
    94.98
    97.17
    99.35
    101.50
    103.70
    105.80
    108.00
    110.20
    112.30
    114.50
    116.60
    118.80
    120.90
    123.00
    125.20
    127.30
    129.40
    131.50
    133.60
    135.80
    137.90
    140.00
    142.10
    144.20
    146.30
    148.40
    150.50
    152.50
    154.60
    156.70
    158.80
    160.80
    162.90
    165.00
    167.00
    169.10
    171.10
    173.20
    175.20
    177.30
    179.30
    181.30
    183.40
    185.40
    187.40
    189.40
    191.50
    193.50
    195.50
    197.50
    199.50
    60
    CMC TECHNICAL REFERENCE MANUAL
    Degrees Celsius versus Ohms value chart for 100 OHM Platinum RTD
    °C
    -17.78
    -12.22
    -6.67
    -1.11
    4.44
    10.00
    15.56
    21.11
    26.67
    32.22
    37.78
    43.33
    48.89
    54.44
    60.00
    65.56
    71.11
    76.67
    82.22
    87.78
    93.33
    98.89
    104.44
    110.00
    115.56
    121.11
    126.67
    132.22
    137.78
    143.33
    148.89
    154.44
    160.00
    165.56
    171.11
    176.67
    182.22
    187.78
    193.33
    198.89
    204.44
    210.00
    215.56
    221.11
    226.67
    232.22
    237.78
    243.33
    248.89
    254.44
    260.00
    0.00
    93.01
    95.20
    97.38
    99.56
    101.74
    103.90
    106.07
    108.22
    110.38
    112.53
    114.68
    116.83
    118.97
    121.11
    123.22
    125.37
    127.50
    129.62
    131.74
    133.86
    135.97
    138.08
    140.18
    142.29
    144.39
    146.48
    148.57
    150.66
    152.74
    154.82
    156.90
    158.98
    161.05
    163.11
    165.17
    167.23
    169.29
    171.34
    173.39
    175.44
    177.48
    179.51
    181.55
    183.58
    185.60
    187.63
    189.65
    191.67
    193.68
    195.69
    197.69
    0.62
    93.22
    95.42
    97.60
    99.78
    101.95
    104.12
    106.28
    108.44
    110.60
    112.75
    114.89
    117.04
    119.18
    121.32
    123.43
    125.58
    127.71
    129.83
    131.95
    134.07
    136.18
    138.29
    140.39
    142.50
    144.59
    146.69
    148.78
    150.87
    152.95
    155.03
    157.11
    159.18
    161.25
    163.32
    165.38
    167.44
    169.49
    171.55
    173.59
    175.64
    177.68
    179.72
    181.75
    183.78
    185.81
    187.83
    189.85
    191.87
    193.88
    195.89
    197.89
    1.23
    93.44
    95.63
    97.82
    100.00
    102.17
    104.34
    106.50
    108.66
    110.81
    112.96
    115.11
    117.25
    119.39
    121.53
    123.65
    125.79
    127.92
    130.04
    132.16
    134.28
    136.39
    138.50
    140.60
    142.71
    144.80
    146.90
    148.99
    151.08
    153.16
    155.24
    157.32
    159.39
    161.46
    163.52
    165.59
    167.64
    169.70
    171.75
    173.80
    175.84
    177.88
    179.92
    181.95
    183.98
    186.01
    188.03
    190.05
    192.07
    194.08
    196.09
    198.09
    1.85
    93.66
    95.85
    98.04
    100.22
    102.39
    104.55
    106.71
    108.87
    111.03
    113.18
    115.32
    117.47
    119.61
    121.75
    123.87
    126.01
    128.13
    130.26
    132.38
    134.49
    136.60
    138.71
    140.81
    142.92
    145.01
    147.11
    149.20
    151.28
    153.37
    155.45
    157.52
    159.60
    161.67
    163.73
    165.79
    167.85
    169.90
    171.96
    174.00
    176.05
    178.09
    180.12
    182.16
    184.19
    186.21
    188.24
    190.25
    192.27
    194.28
    196.29
    198.29
    2.47
    93.88
    96.07
    98.26
    100.43
    102.60
    104.77
    106.93
    109.09
    111.24
    113.39
    115.54
    117.68
    119.82
    121.96
    124.08
    126.22
    128.35
    130.47
    132.59
    134.70
    136.81
    138.92
    141.02
    143.13
    145.22
    147.32
    149.41
    151.49
    153.58
    155.66
    157.73
    159.80
    161.87
    163.94
    166.00
    168.06
    170.11
    172.16
    174.21
    176.25
    178.29
    180.33
    182.36
    184.39
    186.41
    188.44
    190.46
    192.47
    194.48
    196.49
    198.49
    3.09
    94.10
    96.29
    98.47
    100.65
    102.82
    104.98
    107.14
    109.30
    111.46
    113.61
    115.75
    117.90
    120.04
    122.17
    124.30
    126.43
    128.56
    130.68
    132.80
    134.91
    137.02
    139.13
    141.24
    143.34
    145.43
    147.53
    149.61
    151.70
    153.78
    155.86
    157.94
    160.01
    162.08
    164.14
    166.20
    168.26
    170.32
    172.37
    174.41
    176.46
    178.49
    180.53
    182.56
    184.59
    186.62
    188.64
    190.66
    192.67
    194.68
    196.69
    198.70
    3.70
    94.32
    96.51
    98.69
    100.87
    103.04
    105.20
    107.36
    109.52
    111.67
    113.82
    115.97
    118.11
    120.25
    122.39
    124.51
    126.65
    128.77
    130.89
    133.01
    135.12
    137.24
    139.34
    141.45
    143.55
    145.64
    147.73
    149.82
    151.91
    153.99
    156.07
    158.15
    160.22
    162.29
    164.35
    166.41
    168.47
    170.52
    172.57
    174.62
    176.66
    178.70
    180.73
    182.77
    184.80
    186.82
    188.84
    190.86
    192.87
    194.88
    196.89
    198.90
    4.32
    94.54
    96.73
    98.91
    101.08
    103.25
    105.42
    107.58
    109.73
    111.89
    114.04
    116.18
    118.32
    120.46
    122.60
    124.73
    126.86
    128.98
    131.10
    133.22
    135.34
    137.45
    139.55
    141.66
    143.76
    145.85
    147.94
    150.03
    152.12
    154.20
    156.28
    158.35
    160.42
    162.49
    164.56
    166.62
    168.67
    170.73
    172.78
    174.82
    176.86
    178.90
    180.94
    182.97
    185.00
    187.02
    189.04
    191.06
    193.08
    195.09
    197.09
    199.10
    4.94
    94.76
    96.95
    99.13
    101.30
    103.47
    105.63
    107.79
    109.95
    112.10
    114.25
    116.40
    118.54
    120.68
    122.81
    124.94
    127.07
    129.20
    131.32
    133.43
    135.55
    137.66
    139.76
    141.87
    143.97
    146.06
    148.15
    150.24
    152.33
    154.41
    156.49
    158.56
    160.63
    162.70
    164.76
    166.82
    168.88
    170.93
    172.98
    175.03
    177.07
    179.11
    181.14
    183.17
    185.20
    187.22
    189.25
    191.26
    193.28
    195.29
    197.29
    199.30
    5.56
    94.98
    97.17
    99.35
    101.52
    103.69
    105.85
    108.01
    110.16
    112.32
    114.47
    116.61
    118.75
    120.89
    123.03
    125.16
    127.28
    129.41
    131.53
    133.65
    135.76
    137.87
    139.97
    142.08
    144.18
    146.27
    148.36
    150.45
    152.54
    154.62
    156.69
    158.77
    160.84
    162.91
    164.97
    167.03
    169.08
    171.14
    173.19
    175.23
    177.27
    179.31
    181.35
    183.38
    185.40
    187.43
    189.45
    191.46
    193.48
    195.49
    197.49
    199.50
    NOTE: This chart converted from Fahrenheit chart using formula °C= ((°F-32)/1.8)
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    61
    CMC TECHNICAL REFERENCE MANUAL
    Checking the RTD Transmitter
    TMS #3
    1. With control power off, connect a 100-ohm resistor to terminals #3 and #4 of the
    transmitter.
    2. Turn control power on, the OUI reading should be 32°F (0°C) ±5%.
    3. If the reading is not within specification, the transmitter may be faulty.
    BCM
    J2-Floating Analog Inputs, (4-20mA) Channels 1-2
    J1-Grounded Analog Inputs,
    (4-20mA) Channels 3-23
    Pin 25
    Pin 1
    100
    123 4
    OHM
    5%
    Temperature transmitter
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    62
    CMC TECHNICAL REFERENCE MANUAL
    Checking proper operation of the BCM and wiring
    TMS #4
    1. Ensure control power is off. At the affected RTD transmitter, disconnect the wires at
    transmitter terminal #1 and #2. Connect a 4-20mA source to these terminals (Observe
    correct polarity). Power up the control panel and then vary the simulator output.
    2. At 12 mA (50%) the OUI should read 1/2 the RTD transmitter range; 100 or 250°F (37.7
    or 121.1°C). The readout should change as the simulator output is varied.
    3. If the reading on the OUI is incorrect or does not change, turn control power off and
    reconnect the transmitter, remove the wires for this transmitter from J1 and move the 4
    to 20 mA simulator to the respective terminals at connector J1, (see electrical schematic
    for connection points).
    4. Turn control power on and observe the OUI readout while varying the 4-20mA. If the
    reading is correct there is an open or short in the wire or terminals connecting the CMC
    to the RTD transmitter. If reading is not correct the BCM may be faulty.
    BCM
    J2-Floating Analog Inputs, (4-20mA) Channels 1-2
    J1-Grounded Analog Inputs,
    (4-20mA) Channels 3-23
    Pin 25
    Pin 1
    4-20 mA SURCE OR
    2 WIRE SIMULATOR
    LOOP
    ON
    DIAL
    100%
    BATTERY
    CHECK
    OFF
    2 WIRE
    mA OUT
    00.0% - 100%
    00.0%
    XXXXXX
    MODEL CL-XXX
    555
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    63
    CMC TECHNICAL REFERENCE MANUAL
    Valve Control System (VCS)
    Description:
    The BCM generates a 4-20 mA signal for valve control. The signal is wired to the I/P
    (current to pressure) transducer for conversion to a pneumatic signal for positioning the
    inlet or bypass control valve.
    Specification:
    •
    4-20mA input = 3 to 15 psi output
    •
    60 to 120 PSIG instrument air input to I/P
    Troubleshooting:
    The following table identifies typical problems, probable causes, and appropriate
    procedures for verifying the probable cause:
    Typical Problem
    IV or BV not operating
    Probable Cause
    Failure of BCM
    Positioner or actuator malfunction
    Failure of I/P
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Troubleshooting Procedure
    VCS #1
    VCS #2
    VCS #2
    64
    CMC TECHNICAL REFERENCE MANUAL
    Checking proper operation of the BCM and wiring
    VCS #1
    1. With control power off, lift the wires at J3 for the suspected circuit and install a test meter
    capable of reading milliamps as shown below, (the pin numbers are found on the
    electrical schematic).
    2. Restore control power.
    3. If the meter reads 4 mA , the BCM is satisfactory.
    4. If 4 mA is not present, refer to the section titled “Control Power System”.
    5. Restore connections.
    6. Remove control power.
    7. Lift wires at suspected I/P, and install meter as in previous step.
    8. Restore control power.
    If the meter reads 4 mA, the BCM and wiring is satisfactory.
    BCM
    J3-Analog Outputs, (4-20mA) Channels 1-4
    J1-Grounded Analog Inputs,
    (4-20mA) Channels 3-23
    Pin 25
    Pin 1
    Pin 1
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    VDC
    mA
    VAC
    Ω
    mA COM V Ω
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    65
    CMC TECHNICAL REFERENCE MANUAL
    Checking proper operation of the I/P and positioner
    VCS #2
    1. Connect a 4-20 mA simulator to the I/P.
    2. Ensure instrument air is present at the supply connection on the I/P.
    3. Vary the simulator between 4-20 mA. The output of the I/P and the positioner should
    follow. If the valve tracks the 4-20 mA signal correctly the I/P and the positioner are
    satisfactory.
    BATTERY
    CHECK
    LOOP
    ON
    mA OUT
    100%
    OFF
    DIAL
    2 WIRE
    00.0%
    XXXXXX
    MODEL CL-XXX
    4-20 mA SURCE OR
    2 WIRE SIMULATOR
    00.0% - 100%
    555
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    INGERSOLL-RAND
    Centrifugal Compressor Division
    Highway 45 South
    Mayfield, KY. 42066
    Parts Service (800) 247-8640
    66
    CMC TECHNICAL REFERENCE MANUAL
    Pressure Monitoring System (PMS)
    Description:
    A Pressure Transducer (PT) is used to convert pressure (psi) to a 4-20 mA signal for
    monitoring by the CMC.
    Component specification:
    •
    0-50 PSIG (344.75 kPa) range
    •
    0-200 PSIG (1379 kPa) range
    •
    Power = 24 VDC
    Troubleshooting:
    The following table identifies typical problems, probable causes, and appropriate
    procedures for verifying the probable cause:
    Typical Problem
    Zero OUI readout
    Erratic OUI readout
    Incorrect OUI readout
    Probable Cause
    Open circuit/cable disconnected
    Loss of power to transmitter
    Malfunctioning transmitter
    Loose wire/terminal/connector
    Any
    Troubleshooting Procedure
    PMS #1, 2
    PMS #1
    PMS #3, 4
    PMS #1,2
    PMS #1, 2, 3, 4
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    67
    CMC TECHNICAL REFERENCE MANUAL
    Checking for Power to the Pressure Transmitter
    PMS #1
    1. Ensure control power is off. Disconnect the wires at the suspect PT and connect a
    voltmeter to these wires.
    2. With control power on, there should be approximately 24 VDC present at the terminals.
    3. If approximately 24 VDC is not present, see the section titled “Control Power System”.
    BCM
    J2-Floating Analog Inputs, (4-20mA) Channels 1-2
    J1-Grounded Analog Inputs,
    (4-20mA) Channels 3-23
    Pin 25
    Pin 1
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    SPAN
    VDC
    mA
    ®
    VAC
    Ω
    mA COM V Ω
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    INGERSOLL RAND
    68
    CMC TECHNICAL REFERENCE MANUAL
    Checking proper operation of the BCM and wiring
    PMS #2
    1. Ensure control power is off. Disconnect the wires at the suspect PT and connect a 4-20
    mA source to the lifted wires (Observe correct polarity).
    2. Restore control power and then vary the simulator output.
    3. At 12 mA (50%) the OUI should read 1/2 the PT range. The readout should change as
    the simulator output is varied.
    4. If the reading on the OUI is incorrect or does not change, turn control power off and
    reconnect the transmitter, remove the wires for this transmitter from J1 and move the 420 mA simulator to the respective terminals at connector J1, (see electrical schematic for
    connection points).
    5. Turn control power on and observe the OUI readout while varying the 4-20 mA. If the
    reading is correct there is an open or short in the wire or terminals connecting the CMC
    to the PT. If the reading is not correct the BCM may be faulty.
    BCM
    J2-Floating Analog Inputs, (4-20mA) Channels 1-2
    J1-Grounded Analog Inputs,
    (4-20mA) Channels 3-23
    Pin 25
    Pin 1
    4-20 mA SURCE OR
    2 WIRE SIMULATOR
    LOOP
    ON
    DIAL
    100%
    BATTERY
    CHECK
    OFF
    2 WIRE
    mA OUT
    00.0% - 100%
    00.0%
    XXXXXX
    MODEL CL-XXX
    555
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    69
    CMC TECHNICAL REFERENCE MANUAL
    Quick check of the PT
    PMS #3
    1. Connect an ohmmeter to the disconnected wires coming from the PT.
    2. If there is no continuity either the wiring or the PT is faulty.
    M
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    VDC
    mA
    VAC
    Ω
    mA COM V Ω
    SPAN
    ®
    INGERSOLL RAND
    Functional PT test
    PMS #4
    1. Remove control power.
    2. Remove the PT and connect a regulated air supply to the pressure connection. Power
    up the CMC and vary the regulated air supply. The OUI should read the pressure being
    applied.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    70
    CMC TECHNICAL REFERENCE MANUAL
    Digital Input System (DIS)
    Description:
    The digital input devices associated with the CMC are on/off devices that turn on or off the
    associated CMC digital input.
    Typical digital device name and type:
    1.
    Low seal air pressure (Pressure)
    2.
    Low cooling water flow (Flapper)
    3.
    Low oil level (Float)
    4.
    High condensate level (Float)
    5.
    Dirty inlet filter (Differential pressure)
    6.
    Dirty oil filter (Differential pressure)
    7.
    High motor temperature (Thermistor)
    Troubleshooting:
    The following table identifies typical problems, probable causes, and appropriate
    procedures for verifying the probable cause:
    Typical Problem
    False alarm or trip
    Probable Cause
    Faulty device
    Faulty wiring
    Troubleshooting Procedure
    DIS #1
    DIS #1
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    71
    CMC TECHNICAL REFERENCE MANUAL
    Checking proper operation of the digital devices
    DIS #1
    1. Verify approximately 24 VDC is present as described in the section titled
    “Troubleshooting the Power System”.
    2. If approximately 24 VDC is present, install a multimeter with VDC selected between J4
    or J5 pin1 and the input pin (the input pin can be determined from the electrical
    schematic, or wire number).
    3. Ensure the digital device is not in the trip condition, the meter should read 0 VDC.
    4. Actuate the switch, the meter should read approximately 24 VDC.
    J6-RS232 Serial
    Data Link (Display),
    Female DB9
    BCM
    J5-Digital (Discrete)
    Inputs (24 VDC),
    Channels 9-16
    Pin 1
    XXXXX
    XXXXX
    XXXXX
    XXXXX
    J4-Digital (Discrete)
    Inputs (24 VDC),
    Channels 1-8
    XXXXX
    XXXXX
    VDC
    mA
    VAC
    Ω
    mA COM V Ω
    Pin 1
    Seal Air Switch
    J3-Analog Outputs
    (4-20mA)
    Channels 1-4
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    Control Power System (CPS)
    Description:
    The control power system provides 24 VDC to the CMC system for processing logic,
    displaying data, and monitoring instrumentation. The 24 VDC power supply feeds the Base
    Control Module (BCM) at connector J10. Over current protection and power distribution are
    performed as shown below:
    J2
    +24 VDC pins 11 thru 14
    J1
    AC2 pin 3
    Power Supply
    F1
    AC1 pin 1
    Return pins 7 thru 10
    BCM shown
    cover removed
    Fuse 5A/250VAC, normal blo.
    J12-Digital Output Power 120 VAC (Pin 1)
    To OUI J2 pin 2
    To OUI J2 pin 1
    OUI Power
    To Ground Bar
    J10-Power Input (24 VDC)
    F100
    F101
    F102
    F103
    J9-Current Transformer
    (0-5 amp)
    CPU Power
    All BCM Fuses are 5x20mm,
    GMA 1.5 amp, Fast Blow
    BCM
    Digital Input Power
    J4 & J5 - Digital Input Power 24 VDC (pin 1)
    Analog Input/Output Power
    LEGEND:
    Trace
    Wire
    J3- Analog Output Power 24 VDC (pins 2 & 8)
    J1- Analog Input Power 24 VDC (pin 26)
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    Power Supply:
    •
    Input power: 85-132 VAC, or 180-264 VAC (auto-selecting input), 2.5A RMS max, 47-63
    Hz.
    •
    Output power: 24 VDC, 4.3 A maximum at 50 °C.
    Troubleshooting:
    The following table identifies typical problems, probable causes, and appropriate
    procedures for verifying the probable cause:
    Typical Problem
    Probable Cause
    All analog inputs are zero or negative on System Page
    No AC power
    No DC power
    No analog input
    power
    No CPU power
    OUI displays: “INGERSOLL-RAND Centrifugal
    Compressor Division”
    OUI is black
    Event Log indicates all digital alarms and trips active
    All digital outputs not working
    All analog outputs not working
    BCM problems
    No AC power
    No DC power
    No OUI power
    No AC power
    No DC power
    No digital input
    power
    No AC power
    No DC power
    No digital output
    power
    No AC power
    No DC power
    No analog output
    power
    Troubleshooting
    Procedure
    CPS #1
    CPS #2
    CPS #5
    CPS #8
    CMCS #3
    CPS #1
    CPS #2
    CPS #7
    CPS #1
    CPS #2
    CPS #3
    CPS #1
    CPS #2
    CPS #4
    CPS #1
    CPS #2
    CPS #6
    No AC power
    CPS #1
    1. Ensure control power is off.
    2. Install a multimeter set for VAC between pins 1 and 3 at connector J1 on the power
    supply.
    3. Restore control power, the meter should read 120 VAC or 220 VAC depending upon
    the rated supply power. The rated supply power can be verified from the electrical
    schematic.
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    No DC power
    CPS #2
    1. Ensure control power is off.
    2. Install a multimeter set for VDC between pins 11-14 and 7-10 at connector J2 on the
    power supply.
    3. Restore control power, the meter should read approximately 24 VDC. If approximately
    24 VDC is not present, check F1 on the power supply, if fuse is good, the power supply
    may be faulty.
    4. Ensure control power is off.
    5. Install a multimeter set for VDC between pins 1 and 2 at connector J10 on the BCM.
    6. Restore control power, the meter should read approximately 24 VDC. If approximately
    24 VDC is not present, check the wiring between the power supply and the BCM.
    No digital input power
    CPS #3
    1. Ensure control power is off.
    2. Install a multimeter set for VDC between pin 1 at connector J4 on the BCM and the
    ground bar.
    3. Restore control power, the meter should read approximately 24 VDC. If approximately
    24 VDC is not present, check F103 on the BCM, if F103 is good, check for DC power.
    No digital output power
    CPS #4
    1. Ensure control power is off.
    2. Install a multimeter set for VAC between pin 1 at connector J12 on the BCM and the
    ground bar.
    3. Restore control power, the meter should read 120 VAC.
    No analog input power
    CPS #5
    1. Ensure control power is off.
    2. Install a multimeter set for VDC between pin 26 at connector J1 on the BCM and the
    ground bar.
    3. Restore control power, the meter should read approximately 24 VDC. If approximately
    24 VDC is not present, check F102 on the BCM, if F102 is good, check for DC power.
    No analog output power
    CPS #6
    1. Ensure control power is off.
    2. Install a multimeter set for VDC between pin 2 at connector J3 on the BCM and the
    ground bar.
    3. Restore control power, the meter should read approximately 24 VDC. If approximately
    24 VDC is not present, check F102 on the BCM, if F102 is good, check for DC power.
    No OUI power
    CPS #7
    1. Ensure control power is off.
    2. Install a multimeter set for VDC between pins 1 and 2 at connector J2 on the OUI.
    3. Restore control power, the meter should read approximately 24 VCD. If approximately
    24VDC is present, check F2 on the OUI. If F2 is good, go to next step.
    4. Restore control power, the meter should read approximately 24 VDC. If approximately
    24 VDC is not present, check F101 on the BCM, if F101 is good, check for DC power.
    22204796 Rev. B, Version 3.10
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    No CPU power
    CPS #8
    1. Ensure control power is off.
    2. Verify approximately 24 VDC is present at J10.
    3. Check F100, if F100 is blown the BCM must be replaced, not the fuse.
    4. If F100 is not blown, and the BCM is not functioning, the BCM must be replaced.
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    Controller Problems
    Description:
    The CMC System is generally comprised of a Base Control Module (BCM), Operator User
    Interface (OUI), and Power Supply (PS). There are few user serviceable components within
    the system; however, a brief understanding of the system will help in overall
    troubleshooting. All components require 24 VDC and rely on hardware and software to
    perform correctly, if the problem cannot be isolated to a power problem it is most likely a
    hardware or software problem, which will require Ingersoll-Rand support to correct.
    Component Specification:
    •
    VDC power required
    •
    Software required
    Troubleshooting:
    The following table identifies typical problems, probable causes, and appropriate
    procedures for verifying the probable cause:
    Typical Problem
    Probable Cause
    BCM fault suspected
    OUI is dim
    No power
    Wrong contrast selected
    Backlight failing
    No power
    Cable disconnected
    OUI is black
    OUI displays “INGERSOLL-RAND
    Centrifugal Compressor Division”
    OUI displays “Status XXH”
    Where XX is a specific number
    Many
    MODBUS communications problem No power
    Many
    Troubleshooting
    Procedure
    CMCS #4
    CMCS #1
    CMCS #1
    CMCS #2
    CMCS #3
    Refer to Status Codes
    under System Information
    Section.
    CMCS #5
    Refer to the UCM
    Section.
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    BCM Problems
    BCM is not controlling
    CMCS #4
    1. Check the CPU power as described in the section titled “Control Power System”.
    OUI Problems
    OUI is dim
    CMCS #1
    1. Depress the contrast key to step to the desired brightness.
    2. Replace the OUI backlight as described in the section titled “Backlight Replacement
    Procedure”. If the backlight does not fix the problem the OUI may be faulty.
    OUI is black
    CMCS #2
    1. Check for OUI power as described in the section titled “Control Power System”. If
    approximately 24 VDC is present, check F2. If F2 is O.K. the OUI may be faulty.
    OUI displays “INGERSOLL-RAND Centrifugal Compressor Division”
    1. Check the cabling between OUI J1 and BCM J6.
    2. The BCM may require programming.
    3. Check the BCM CPU power.
    4. The BCM may be faulty.
    CMCS #3
    UCM Problems
    All UCM LED’s are not lit
    1. Check for approximately 24 VDC at pins 1 and 2 at J3 on the UCM.
    2. If power is present at J3 the UCM may be faulty.
    22204796 Rev. B, Version 3.10
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    Options
    This section details the various standard options that are available for the CMC. Some of
    the options listed are provided standard on some models, and will be indicated as such.
    Enclosures
    The CMC has three panel enclosures available; NEMA 12 (IP 64), which is standard, and
    optional NEMA 4 (IP 65) and NEMA 4X (IP 65). The panel is machine mounted. All
    electrical devices are mounted and wired where practical.
    NEMA 12 (IP 64)
    NEMA 12 is the standard enclosure for all compressors with CMC panels. NEMA defines
    this rating as "... intended for indoor use primarily to provide a degree of protection against
    dust, falling dirt, and dripping non-corrosive liquids. They shall meet drip, dust, and rustresistance design tests. They are not intended to provide protection against conditions such
    as internal condensation.” Typically this type of enclosure is applied for most indoor
    applications.
    Cooling Fan
    The cooling fan is supplied on all standard CMC enclosures, where a wye-delta motor
    starter is present, the Control Electrical Package is included, or the ambient temperature
    exceeds 40°C keeps the internal temperature below the maximum operating temperature
    allowed. This action effectively extends the operating life of the control components. A filter
    and gasket are added to attain a NEMA 12 rating.
    NEMA 4 (IP 65)
    This optional enclosure type is applied for most outdoor applications. Indoor applications
    that are subject to hose washing would also apply to this standard. NEMA defines this
    rating as "... intended for indoor and outdoor use primarily to provide a degree of protection
    against windblown dust and rain, splashing water, and hose directed water; and to be
    undamaged by the formation of ice on the enclosure. They shall meet hose down, external
    icing, and rust-resistance design tests. They are not intended to provide protection against
    conditions such as internal condensation or internal icing."
    The standard panel enclosure is replaced with a new box that meets the above
    requirements. The User Terminal vinyl overlay and sealing bezel is door mounted and
    allows direct interface with the environment. NEMA 4 rated lights, switches and buttons are
    mounted directly through the panel door. A panel space heater and Vortex Tube Cooler are
    added to accommodate changes in ambient temperatures.
    NEMA 4X (IP 65)
    Also an optional enclosure type that should be applied in the same type of NEMA 4
    applications within corrosive environments. The basic difference between NEMA 4 and
    NEMA 4X is that the panel enclosure is constructed with stainless steel.
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    Space Heater
    Required for NEMA 4 and NEMA 4X panels to protect the panel from internal condensation.
    This option should also be used with NEMA 12 for unheated building applications.
    Vortex Tube Cooler
    This panel cooler is required on NEMA 4 and NEMA 4X enclosures to maintain the
    operating temperature below the maximum. An adjustable thermostat is provided to open
    and close a solenoid operated valve from the instrument air header in the panel. The cooler
    works by converting filtered compressed air into a hot air stream and cold air stream. The
    hot air stream is vented external to the enclosure and the cold air stream is directed into the
    enclosure.
    Type Z Purge
    The CMC requires a Type Z Purge when the customer environment is Division 2. A Type Z
    Purge reduces the classification within an enclosure from Division 2 too non-hazardous.
    When provided, a NEMA 4 or NEMA 4X enclosure is required. Hand valve selectable quick
    and slow purges, with flow meters are provided to regulate the amount of gas entering the
    panel. A differential pressure switch is wired to a light on the front of the panel to indicate if
    there is a loss of purge gas. A relief valve is installed to prevent over-pressurization and a
    warning label, text below, is affixed to the front of the panel.
    WARNING
    Enclosure shall not be opened unless the area is known to be non-hazardous
    or unless all devices within the enclosure have been de-energized. Power shall not
    be restored after the enclosure has been opened until combustible dusts have been
    removed and the enclosure re-pressurized.
    Fused Control Power Disconnect
    As a safety precaution, this option removes power from the panel before the door is
    opened. By turning the rotary door handle, the panel power is terminated. If the disconnect
    is to include fuse size provisions for the main motor starter, additional information is
    required. The disconnect would have to be mounted external to the panel enclosure. The
    short circuit capacity, maximum ground fault, motor full load amps, motor locked rotor amps
    and motor voltage must be known to size the disconnect properly. Pricing varies depending
    upon the size, amp rating of the fuse, which is required for protection.
    NOTE
    This option does not make fuse size provisions for the main motor starter.
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    Control Electrical Package
    The Control Electrical Package consists of a Control Transformer, Prelube Pump Starter,
    Oil Heater Contactor(s) and Transient Voltage Surge Suppressor. This option allows the
    customer to bring a single source of electrical power to the compressor to run all of the
    compressor package accessories; thereby, making compressor installation easier.
    Stage Data Package
    For monitoring of interstage pressure and temperatures, the Stage Data Package can be
    added. As standard, the CMC comes with temperature readout, alarm and trip for the next
    to last compression stage and compressor discharge pressure indication. When selected,
    each stage gets temperature and pressure measurements on the downstream side of each
    stage's cooler. For compressors without built-in aftercoolers, the last stage diffuser
    temperature is measured. Each temperature has readout, alarm and trip capability while the
    pressures are readout only.
    Alarm Horn
    The optional alarm horn sounds any time there is an alarm or trip situation. The horn output
    will pulse for an alarm and remain constant for a trip. This allows the operator to distinguish
    between each fault type without viewing the OUI. The horn silence push-button is located
    on the CMC faceplate to silence any audible devices connected to the CMC board.
    Running Unloaded Shutdown Timer
    The intent of this option is to save energy by shutting the compressor off during extended
    periods of unloaded operation. When the running unloaded shutdown timer is enabled with
    the RUNNING UNLOADED SHUTDOWN TIMER DISABLED/ENABLED selector switch,
    the auto-dual control mode should be selected, this provides for automatic unloading of the
    machine during periods of low demand.
    Water Solenoid Post Run Timer
    This optional panel function is used to shut off water flow to the air and oil coolers after the
    compressor is stopped. It is accomplished by sending a signal to close the solenoid
    operated water valve(s).
    Panel Mounted Wye-Delta Starter
    Main motor starter enclosed in the CMC panel. This feature allows the customer to wire the
    compressor from a single source; thereby, eliminating most electrical wiring and starter
    installation expense. These starters are available for compressors with motors up to 350
    HP and 575 Volts.
    N.O. Contact for Remote Indication of Common Alarm and
    Trip
    A normally open contact for individual remote indication closes whenever an alarm or trip
    occurs. This allows a customer to have remote indication of compressor alarm, trip or both.
    Power Regulating Constant Voltage Transformer
    If the electrical power supplied to the CMC varies more than ten percent, this transformer
    must be added to bring the voltage within the specification requirements.
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    Automatic Starting
    NOTE
    Most electric motors are only rated for two cold starts or one hot start per hour. It is
    the operator’s responsibility not to exceed the electric motor’s limitation. The control
    system allows the compressor to be started when the compressor is ready, not the
    motor.
    Remote start and stop through hard wiring to the compressor control panel, communicating
    through the MODBUS port via RS422/485, Auto-Hot Start and Auto-Cold Start are the four
    options for automatically starting and stopping with the CMC. With each of these options a
    REMOTE COMMUNICATIONS DISABLED/ENABLED or REMOTE FUNCTIONS
    DISABLED/ENABLED, selector switch is provided on the device plate with a REMOTE
    ENABLED light. Since each option performs basically the same function, only one should
    be purchased for a single CMC. The specific method selected depends upon the
    application.
    Remote Start and Remote Stop – Hardwired
    When this option is purchased, two digital inputs are configured on the CMC Base Control
    Module, one for remote start and one for remote stop.
    Remote Start Digital Input
    This input is driven by a momentary contact closure of at least 120 milliseconds. For the
    start to proceed, the panel power must be on, the compressor must be in the Ready state
    (all utilities must be running and permissive functions satisfied) and the REMOTE
    FUNCTIONS DISABLED/ENABLED selector switch is in ENABLED mode prior to
    energizing the input.
    Remote Stop Digital Input
    This input is driven by a maintained contact closure. The remote stop input is always active;
    that is, the remote stop can be initiated regardless of the REMOTE FUNCTIONS
    DISABLED/ENABLED selector switch position.
    Communications
    Remote starting and stopping can be accomplished through the MODBUS communication
    port in various ways. See the section on Communications that follows for these options.
    Again, panel power must be on, all utilities must be running and permissive functions
    satisfied in order for the start-up to proceed.
    Auto-Hot Start
    Normally purchased in multiple compressor applications where backup air is required, this
    automatic starting option allows the compressor to be started when the system air pressure
    is below a user selected set point pressure.
    Panel power must be on, all utilities must be running, the AUTO HOT START
    DISABLED/ENABLED selector switch must be in the ENABLED position and all permissive
    functions satisfied in order for the start-up to proceed. Solenoid water valve(s) are provided
    for the intercooler(s) to reduce water consumption when the compressor is not running. A
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    post run timer is also included in the Auto Hot Start logic to de-energize the water solenoid
    valves twenty minutes after a compressor stop or trip to allow the oil to cool.
    Auto-Cold Start
    This option is very similar to Auto-Hot Start with the exception that the compressor starts
    with no initial panel power. An additional timer is added to simulate the start button being
    pressed and another timer is added to bypass the low oil temperature function on start-up.
    One additional solenoid valve is included for instrument air supply. The CONTROL POWER
    OFF/ON selector switch label is modified to CONTROL POWER LOCAL/OFF/COLD
    START. When in the COLD START position, the compressor is OFF and can be started
    through the Auto-Cold Start function. As a safety precaution, an optional strobe light can be
    provided to indicate that an automatic start is about to begin.
    Remote 4-20 mA Pressure Setpoint
    When the REMOTE FUNCTIONS DISABLED/ENABLED selector switch is in the ENABLED
    position, the CMC will monitor the specified analog input for pressure setpoint. If this analog
    input’s value minus the Pressure Setpoint (from the display) is greater than or equal to the
    display’s Pressure Setpoint step value (default 0.1 psi), a remote setpoint change will be
    requested. This request will be initiated, as long as there are no analog input error faults for
    this channel, and the change made will rounded to the nearest step value (0.1) size. This
    methodology prevents the control system from chasing an ever-changing analog input
    value.
    Ambient Control plus Parallel Valve Control Logic
    Ambient Control
    This feature uses Polytropic Head (or just Head) as the MinLoad control variable. By using
    Head, a more conservative MinLoad setting can be established which contributes to energy
    efficiency. For additional information on Polytropic Head, see section under SURGE
    CONTROL / Control Methodology.
    Polytropic Head may be selected as the MinLoad control variable for Pressure Control (the
    standard process control for the CMC), or optional Flow Control. Polytropic Head may also
    be selected as the MinLoad control variable for Steam and Gas Turbine Driven and Diesel
    Driven Compressors.
    Parallel Valve Control Logic
    This feature includes a number changes to control logic to improve valve transitions.
    •
    One feature is improved State Transitions. The overall effect will be better
    response to system dynamics requiring state changes.
    An example of this is inlet valve throttling. When the machine is rapidly throttling
    from Loaded State to the MinLoad state, the inlet valve will transition to MinLoad
    before actually reaching the Minload setpoint. The valve transition offset is a
    function of the PID settings for the MinLoad and Loaded loops and the rate at which
    the process control variable is rising. By making this transition early, improved
    control response is achieved. In this case, undershoot of MinLoad would be
    decreased and overshoot of the process variable would be decreased relative to
    previous CMC releases.
    •
    For installations with big, quick swings in load that get the check valve opened and
    closed frequently a new Discharge Pressure Regulation feature may be selected
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    to provide better pressure control. Previously these large changes required the
    MinLoad to be set more conservatively. Otherwise if the controller could not react
    fast enough the system would decay while closing the bypass valve.
    This new control loop will regulate compressor discharge pressure when the
    discharge check valve is closed. Adding this loop also eliminates windup of the
    bypass valve and allow for quicker reentry into the system. This feature requires
    configuration by an Ingersoll-Rand service technician.
    •
    Typically, overshoot can occur when the system being regulated has a significant
    change in dynamic response and the PID parameters are not changed accordingly.
    For compressor control, this happens when the controller used the same bypass
    valve PID values for control regardless of the check valve state. One way to handle
    this is with the above Discharge Pressure Regulation feature previously described.
    If the installation does not warrant setting up Discharge Pressure Regulation, the
    Loading Ramp rate feature is used to accommodate this check valve complication.
    The Loading Ramp feature minimizes overshoot upon a load command.
    •
    An additional feature called Unloading Interrupt is also a part of the CMC. The
    unloading state can now be interrupted by a load command and reload the machine
    without completely unloading it.
    •
    Deadband on Control Variables is another feature of Parallel Valve Control Logic.
    This feature prevents valve oscillations when the Process Variable is steady state.
    Steady state valve oscillation is primarily a result of the control valve’s inability to
    position as finely as required by the PID control loop. A typical scenario would be
    when the CMC commands the valve to open 0.05% and the valve opens 0.1%. The
    valve now needs to close 0.05% but will likely close 0.1% causing the cycle to start
    over. This feature requires configuration by an Ingersoll-Rand service technician.
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    Mass Flow Control
    Constant flow control is a performance control method for Centac air compressors.
    Uncontrolled, the compressor's
    discharge flow would rise and fall
    along the natural performance
    Surge Line
    curve as system flow demand
    changed. Constant Flow control
    Maximum
    satisfies the constant flow
    Throttle Points
    (MinLoad)
    Discharge
    requirement.
    Pressure
    This performance map shows
    Constant Flow control. Constant
    Flow control maintains the
    compressor discharge flow into the
    system at the Flow Setpoint as
    entered into the CMC by the user.
    Once loaded, the compressor will
    operate along the constant flow
    line until the user presses the
    Unload or Stop button.
    Natural
    Pressure
    Curve
    Design
    Point
    Constant
    Flow Line
    Unloaded
    Natural
    Power
    Curve
    Surge Line
    Power at
    Control is accomplished by
    Coupling
    modulating the inlet valve within
    the compressor's operating range.
    When the compressor’s demand is
    Unloaded
    less than the minimum throttled
    capacity, constant flow is
    Capacity
    maintained by modulating the
    bypass valve and venting some or
    all of the air to atmosphere. This
    Figure 20: Constant Flow Control
    valve is opened just prior to reaching
    the surge line. Whenever the bypass valve is open, the inlet valve maintains its position at
    the minimum throttled capacity setting. Constant Flow provides a constant discharge flow
    with variable pressure up to the natural surge point.
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    Measuring the Flow
    In order to maintain constant flow, the system discharge airflow must be measured. A flow
    transducer is mounted in the customer’s piping upstream of the check valve.
    CMC
    4-20 mA
    Bypass
    Valve
    FT
    4-20 mA
    Base
    Control
    Module
    CT
    Starter
    Motor
    4-20 mA
    Check
    Valve
    FE
    Compressor
    PT
    x
    Inlet
    Valve
    4-20 mA
    Figure 21: Measuring Flow
    This transducer sends a 4-20 mA signal to the CMC board. The CMC compares the
    measured flow to the flow setpoint entered into the CMC by the user through the Operator
    User Interface (OUI). Depending upon the difference between these two values the CMC
    will send a 4-20 mA signal to open or close the inlet and/or bypass valve to maintain the
    specified compressor flow setpoint.
    Steam and Gas Turbine Driven Compressors
    The following describes the differences between the motor and turbine driven compressor
    logic.
    Performance Control
    Motor Current, MinLoad and MaxLoad
    Steam and gas turbines do not have motor current, MinLoad and MaxLoad operate
    differently form the normal motor driven compressor. MinLoad uses an inlet valve position,
    instead of amps, to determine when to transition from Inlet Valve Pressure control to
    Bypass Valve Pressure control. When in MinLoad, the controller uses this valve position as
    the setpoint for the Inlet Valve MinLoad PID loop. Since the controlled variable and the
    setpoint variable are identical, the goal of tuning this loop is to get a steady output. The
    default parameters will satisfy most all applications. The procedure for determining the
    MinLoad point is the same for both motor and turbine driven units, except inlet valve
    position is recorded instead of motor amps.
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    CAUTION
    Improperly tuning MinLoad PID values will result in unpredictable compressor
    operation. If this situation arises, reset the PID values to the default values.
    MaxLoad situations are detected on turbine driven compressors by low speed. The
    MaxLoad setpoint is a speed below the rated speed and above the low speed alarm. This
    speed is determined by adding an offset to the low speed alarm. This offset is the speed
    that the governor can accurately control.
    Surge Control
    All surge related issues are identical to motor driven units with the exception of the
    detection methodology.
    How Surge is Detected
    The CMC senses surge when the rate of change in last stage discharge pressure is greater
    than the surge sensitivity setpoint value.
    The difference between this and motor
    Compressor Operating States
    driven units is that the motor driven units
    Turbine Driven Packages
    uses rate of change in motor amps also.
    Compressor Operating Methodology
    Comparing the chart to the right for
    Turbine driven compressor and Motor
    driven compressor, the only state
    differences are the addition of the first
    three states under Rotating. These are
    Accelerate-1, Accelerate-2 and Slow
    Rolling.
    Accelerate-1
    +
    Compressor
    +
    Stopped
    Waiting
    Not Ready
    Ready
    +
    Rotating
    Accelerate-1
    Accelerate-2
    Slow Rolling
    This state is provided to give the operator
    Starting
    five minutes from the time the Start button
    Unloaded
    is pressed to get enough steam to the
    turbine to get the speed above the Zero
    A-D Unloaded
    Offset Speed. This speed is defaulted to
    Surge Unload
    15 rpm. If this speed is not achieved in
    Loading
    this time period, the event message
    MinLoad
    “Accelerate-1 Fail” will appear and the
    controller will trip the compressor. As
    Loaded
    always, the compressor must be “Ready”
    Full Load
    before the start button is pressed. The
    MaxLoad
    reason for the five-minute limitation is to
    Unloading
    prevent the compressor from being ready
    for an indefinite period of time. This
    Coasting
    prevents the operator from forgetting that
    the compressor is ready to accelerate. “Accelerate-1” could also be explained as
    “accelerating to zero speed offset” or “waiting for compressor rotation”.
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    Accelerate-2
    After the transition to Accelerate-1 is complete, this state is initiated when rotation is
    detected and the turbine has not reached the low trip speed. This state may be bypassed if
    the turbine accelerates very quickly.
    Once in this state, a sixty (60) second timer is initiated. If the speed does not get to the
    minimum slow roll speed within this time period, the event message “Accelerate-2 Fail” will
    appear and the controller will trip the package. This state is limited sixty (60) seconds to
    prevent bearing damage from rolling the compressor at too low a speed. The bearing
    design requires a minimum speed to form the oil film thickness required for proper bearing
    operation. “Accelerate-2” could also be explained as “accelerating to minimum slow roll
    speed”.
    Slow Rolling
    After the transition to Accelerate-2 is complete, this state is entered after the previous sixtysecond timer has elapsed and the speed is less than the low trip speed. The compressor
    can operate in this “Slow Rolling” state indefinitely. While in this state, if the speed drops
    below the minimum slow roll speed, the event message “Slow Roll Fail” will appear and the
    controller will trip the compressor. If at any time during “Slow Rolling” the speed exceeds
    the maximum slow roll speed, the compressor will transition to “Starting”. The Starting state
    for turbine driven compressors is the same as for motor driven compressors.
    Quick Start Turbines
    Quick Start turbines may skip “Accelerate-2” and “Slow Rolling” or just “Slow Rolling”
    because of the acceleration characteristics. The acceleration sequence depends upon the
    acceleration characteristics for a given turbine.
    Operator User Interface (OUI)
    Status Bar
    Motor driven compressors have an optional Compressor Status Field for Start Disabled.
    This field is standard for turbine driven compressors and it means that the turbine trip and
    throttle valve limit switch has not been made.
    System Folder
    Replacing “Motor Current “with” Compressor Speed” on Page 1 is the only modification to
    this folder.
    Info Folder
    The events “Starter Failure” and ”Loss of Motor Current have been deleted from the
    possible event list. The following events have been added.
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    Possible Events List
    Event Name
    Description
    Accelerate-1 Fail
    The zero offset speed has not been achieved before the end of the five-minute timer.
    Accelerate-2 Fail
    The minimum slow roll speed has not been achieved before the end of the one-minute timer.
    Driver Trip
    The trip and throttle valve limit switch has been latched, then unlatched.
    Governor Common Trip
    The governor has tripped.
    High Speed Alarm
    The indicated speed is greater than or equal to the High Speed Alarm setting.
    High Speed Trip
    The indicated speed is greater than or equal to the High Speed Trip setting.
    Illegal Rotation
    Rotation has been detected when in “Stopped”.
    Low Speed Alarm
    The indicated speed is less than or equal to the Low Speed Alarm setting.
    Low Speed Trip
    The indicated speed is less than or equal to the Low Speed Trip setting.
    Slow Rolling Fail
    The minimum slow roll speed was not maintained during “Slow Roll”.
    Starting Fail
    The low trip speed was not achieved before the end of the Starting Timer.
    TTV Switch Fault
    The trip and throttle valve (TTV) limit switch is made when the (TTV) solenoid is de-energized.
    Settings Folder
    For Page 2, Anti-Surge and Driver Over-Load Protection …
    1. “MaxLoad (HLL), amps” is replaced with “MaxLoad (HLL), rpm”.
    2. “User Setpoint (TL), amps” is replaced with “User Setpoint (TL), IV Pos %”.
    3. “Control Setpoint, amps” is replaced with “Control Setpoint, IV Pos %”.
    4. “Surge Index Increment, amps” is replaced with “Surge Index Increment, IV Pos %”.
    For Page 5, Miscellaneous
    1. “CT Ratio” is removed.
    2. “Motor Failure Trip Enable” checkbox is removed.
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    General Sequence of Operation
    Compressor Operating States
    Coasting
    Unloaded
    Unloading
    MaxLoad
    Full Load
    Loaded
    MinLoad
    Loading
    Unloaded
    Starting
    Ready
    Not Ready
    Waiting
    for Turbine and Diesel Driven Packages
    Any
    Stops or
    Trips
    Mechanical Trip (110%)
    Overspeed Trip (108%)
    Overspeed Alarm (105%)
    Rated "Full Load" (100%)
    MaxLoad (HLL)
    Low Alarm (95%)
    Low Trip (93%)
    SPEED
    Maximum Slow Roll (50%)
    Minimum Slow Roll (25%)
    No
    Stops or
    Trips and
    Latch
    Start
    Zero Speed Offset (15 rpm)
    (0%)
    Power
    On
    Stopped
    Rotating
    Starting Methodology
    1. The panel power is turned on. The compressor is WAITING.
    2. The CMC Panel mounted switch for DRIVER SPEED RATED/IDLE (when supplied for
    an electronic governor) should be put into the IDLE position. This switch is wired to a
    discrete input (Driver Speed Rated/Idle) in the CMC and is sent on the discrete output
    (Driver Speed Rated/Idle) to the governor.
    3. When the two-minute waiting timer has expired, the compressor is NOT READY.
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    4. Reset the governor to clear any trip signals. This may be accomplished with the digital
    output (Reset – Momentary). If an electronic governor exists, a discrete output signal
    (Common Trip) is sent from the governor to a discrete input signal on the CMC when
    the governor needs to trip the compressor. If no electronic governor exists, a jumper
    must be installed on the CMC board.
    Adaptive StartingTM Techniques
    Low Trip (93%)
    Starting
    Starting
    Starting
    SPEED
    Slow Rolling
    Maximum Slow Roll (50%)
    Accelerate-2
    Accelerate-2
    Minimum Slow Roll (25%)
    Accelerate-1
    Accelerate-1
    Accelerate-1
    Zero Speed Offset (15 rpm)
    (0%)
    5. When NO Trips exist (compressor and turbine), the CMC energizes the turbine’s trip
    and throttle valve (TTV) solenoid. This is accomplished through a discrete output (Driver
    Permissive) from the CMC to the TTV solenoid.
    6. At this point, the compressor is NOT READY, Driver Disabled.
    7. When the TTV solenoid is energized, the turbine trip valve can be latched.
    8. When the turbine trip valve is manually latched, the turbine trip valve’s limit switch will
    be energized. This signal is sent to a discrete input (Trip and Throttle Valve Limit
    Switch) on the CMC.
    9. When the limit switch is energized and no stop command is pending, the compressor
    will be READY. This state may be maintained indefinitely.
    10. The Start Key is pressed on the compressor. The digital output (CR1) is energized to
    actuate the solenoid operated steam valve and the digital output (Start – Momentary) is
    energized. A timer (five minute maximum) is started. At this point, enough steam should
    be applied to the turbine to get the speed above the zero speed offset. This period is
    ACCELERATE-1.
    11. Once the zero speed offset has been established, a one minute timer is provided to
    prevent compressor pinion damage from rotating the pinions at too low a speed for an
    excessive time. The compressor bearings are designed to have a minimum oil film
    pressure created by a minimum rotating pinion speed. Therefore, we must not stay at
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    too slow a speed for an extended period. This is ACCELERATE-2. The turbine must
    reach the Minimum Slow Roll Speed (approximately 25% of Full Speed) to continue.
    12. Once the turbine gets past the Minimum Slow Roll Speed and is less than the Maximum
    Slow Roll Speed (approximately 50% of Full Speed), the turbine is in the slow rolling
    zone and the compressor is SLOW ROLLING. The User may leave the compressor in
    this mode indefinitely. The CMC monitors the compressor speed (through the speed
    analog input) in this mode. The Idle/Rated Driver Speed switch is turned to the Rated
    position.
    13. When the turbine speed exceeds Maximum Slow Roll Speed, the Starting Timer begins
    (60 seconds maximum) and is STARTING. This is the same time for motor driven
    compressors; therefore, the User must put enough steam to the turbine to get the speed
    above the low trip speed before the timer expires. At this point, the compressor has
    started and runs as described elsewhere.
    Instrumentation for Turbine Driven Compressors
    Centac Microcontroller
    Discrete Outputs (DO)
    CR1
    TTV Solenoid Energize (Driver Permissive)
    TTV Limit Switch
    Start - Momentary
    Stop - Momentary
    Reset - Momentary
    Driver Speed Rated/Idle
    DI
    Discrete Inputs (DI)
    DO
    Common Trip
    Electronic
    Governor
    AO
    Driver Speed
    Rated/Idle
    Switch
    on Panel
    Door
    Analog Input (AI)
    Speed
    AI
    Speed
    Turbine
    TTV Solenoid
    Manual Latch
    Limit Switch
    Steam
    Throttle Valve
    Trip Valve
    Solenoid Steam Valve
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    Diesel Driven Compressors
    Diesel driven compressors have similar characteristics as the turbine driven compressors.
    The differences are…
    1. “Idle/Rated Driver Speed” discrete input and discrete output are eliminated.
    2. “Start – Momentary”, “Stop – Momentary” and “Reset – Momentary” discrete outputs
    are eliminated.
    3. “Driver Permissive” discrete output is wired to the “Trip and Throttle Valve Limit
    Switch” discrete input.
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    93
    Communication
    Customers may want to communicate to the CMC control systems for remote compressor
    control and monitoring. This communication capability provides for flexibility in the
    customer's compressed air operation through remote start and stop, data gathering for
    preventative maintenance, and incorporation into plant-wide control system.
    The major avenue for communicating with the CMC is via MODBUS protocol over an
    RS422/485 hardware link. This requires hardware for the control panel, and a
    communications device with the appropriate driver software to perform the desired panel
    functions. The RS422/485 interface can communicate with any serial device that has an
    RS422 or RS485 port. The customer or his representative must write system software to
    suit his individual needs for remote control and monitoring. Since the customer writes this
    interface, the system can be as flexible as the customer desires.
    Human Machine Interface (HMI) Systems
    Air System Controller (ASC) and Air System Manager (ASM) are software packages
    available for compressors with CMC panels.
    ASC and ASM are graphical integration software specifically developed for air compressor
    systems. Both provide energy management through load sharing and reduction of air
    bypass by using a minimum amount of energy to meet the system demand. The primary
    goal of both systems is to maintain stable system pressure, to integrate, monitor and control
    the compressed air system.
    ASM is the integration of compressor control software in an off-the-shelf Supervisor Control
    and Data Acquisition (SCADA) package that is available from various manufacturers. The
    ASM provides more custom features than does ASC.
    Both ASC and ASM provide a window into the compressor room by making the raw data
    from compressors and other equipment available to plant operators and managers in
    formats that are easy to understand.
    Implementing the CMC in any HMI system may require additional hardware and/or software
    upgrade.
    Direct CMC Communications with RS422/485
    For the descriptions that follow, a serial device can be a Personal Computer (PC),
    Programmable Logic Controller (PLC), Distributed Control System (DCS) or any other
    device that can transmit, receive and interpret an RS422/485 formatted signal over a
    hardware link. In the descriptions that follow, the PC and PLC serial devices are not specific
    to manufacturers or operating systems.
    There are many ways of interfacing to CMC control systems through an RS422/485 port.
    Most of the following methodologies are currently available; but please be aware, other
    possible configurations can exist.
    All RS422/485 interfaces require custom interface software and custom application
    software. The interface software allows a specific serial device and operating system to
    transmit, receive and interpret data from a CMC control system. The application software
    tells the CMC control system what to do; for example, start compressor when ready, stop
    compressor after midnight and retrieve the current data and save to a disk file.
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    Currently there are hundreds of different serial devices using different operating systems
    and languages in the industrial equipment world. Therefore, the practicality of having an
    interface for many systems is limited. Custom interfaces must be written as required by the
    hardware and operating system used.
    The capabilities of the hardware and the imagination of the developer only limit the
    application software. For example, one developer may have two compressors. In this
    application the developer wants a screen to display the compressor interstage pressure
    and temperatures for both machines with various other compressor data. A second
    developer has five compressors. He also wants to display the same data, but this time for
    all five machines. The only way this is done is through changing the application software
    (custom modification).
    The developer may write functions to read and display data, log that data to some magnetic
    media for storage, change compressor set points, sequence the compressors for efficient
    operation and network additional devices, such as pumps, dryers, etc., into the system. All
    of these functions require specially written application software for the intended use.
    The CMC-MODBUS Interface
    Introduction
    The CMC can communicate with other devices over a variety of communications standards.
    Supported standards, or protocols, include RS-232, IRBUS (Ingersoll-Rand Proprietary),
    and Modicon’s MODBUS. The built-in ports on the CMC’s optional Universal
    Communication Adapters access communications. The CMC-MODBUS Interface defines
    the message structure that a CMC uses to exist on a MODBUS network. This interface will
    allow the MODBUS network to gather information and control the compressor.
    NOTE
    Unless specified otherwise, numerical values (such as addresses, codes, or data) are
    expressed as decimal values in the text of this section. They are expressed as
    hexadecimal values in the message fields of the examples.
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    In order to communicate over other types of
    networks, a network adapter must be used. The
    information presented in the following sections does
    not include MODBUS protocol details like framing
    messages and calculating checksums. This detailed
    information can be obtained from Schneider
    Automation’s MODBUS PROTOCOL Manual,
    Chapters 1 through 6. This can be obtained through
    the Internet at “www.modicon.com”.
    Query
    Master
    Slave
    Device
    Address
    Device
    Address
    Function
    Code
    Function
    Code
    Data
    Address
    Byte
    Count
    Data
    Data
    CRC
    CRC
    Serial Modes
    MODBUS Controllers can be setup to communicate
    on MODBUS networks using either of two
    transmission modes: ASCII or RTU. The CMC
    supports only the RTU mode. The user must
    specify the serial port communication parameters
    (baud rate, parity mode, etc.) during configuration of
    each CMC. The mode and serial parameters must
    be the same for all devices on a MODBUS network.
    Response
    Figure 22: MODBUS Messages
    MODBUS Messages
    A MODBUS network uses a master-slave relationship. The CMC always acts as a slave
    device. The slave cannot initiate a message, and returns a message (response) only to
    queries (reads) that are addressed to them individually. For example, a force coil command
    (write to module) that is broadcast to all MODBUS devices would not get a response.
    Responses are not returned to broadcast writes from the master.
    Device Address
    This address is the physical address of the Universal Communication Module (UCM) for the
    compressor. This address must be unique in the MODBUS network. The valid range for this
    address is 01-FF (hexadecimal). NOTE: 00 (hexadecimal) is reserved for broadcast.
    Configuration of the slave address is available through the Ingersoll-Rand Service Tool and
    will be provided by a certified Ingersoll-Rand Service Representative.
    Function Code
    The listing below shows the function codes that are supported by the CMC. Additional detail
    about each function is provided in sections that follow.
    Function Code
    (decimal)
    1
    2
    3
    4
    5
    6
    15
    16
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    Function Code
    (hex)
    01
    02
    03
    04
    05
    06
    0F
    10
    Function Name
    Read Coil Status
    Read Input Status
    Read Holding Registers
    Read Input Registers
    Force Single Coil
    Preset Single Register
    Force Multiple Coils
    Preset Multiple Registers
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    CMC TECHNICAL REFERENCE MANUAL
    Data Addresses
    Addresses that contain the data type and a four-digit number are referred to as absolute
    (e.g., address 30232, where 3 is the data type for a input register and 0232 or 232 is the
    address). Software products at the operator or user level use absolute addresses most
    frequently.
    The addresses that do not contain the type and are referenced to zero are referred to as
    relative (e.g., absolute address 30232 would be relative address 231, remove the data type
    3, holding register, and subtract 1 for referencing to zero). All data addresses in MODBUS
    messages (typically, behind the scenes at the programming communication level) are
    referenced to zero; that is, the first occurrence of a data item is addressed as item number
    zero.
    Reference
    Data Type
    0x
    1x
    3x
    4x
    Coils
    Discrete Inputs
    Input Registers
    Holding Registers
    MODBUS Range
    Absolute
    Addresses
    00001-09999
    10001-19999
    30001-39999
    40001-49999
    MODBUS Range
    Relative
    Addresses
    0000-9998
    0000-9998
    0000-9998
    0000-9998
    CMC Range
    Absolute
    Addresses
    00001-09000
    10001-19000
    30001-39000
    40001-49000
    CMC Range
    Relative
    Addresses
    0000-8999
    0000-8999
    0000-8999
    0000-8999
    •
    Absolute address for Coil 00127 decimal is relatively addressed as coil 007E hex (126
    decimal)
    •
    Input register with absolute address of 30001 is relatively addressed as register 0000 in
    the data address field of the message. The function code field that specifies reading or
    writing data already specifies an input register operation; therefore, the 3x reference is
    implicit.
    •
    Holding register with an absolute address of 40108 is relatively addressed as register
    006B hex (107 decimal)
    Single Module Addresses
    The addresses provided in this document are for compressors with a single Base Control
    Module.
    Multiple Module Addresses
    For those systems that require multiple Base Control Modules, the addresses for the first
    module will be as provided within this document. The addresses for the second module will
    be provided as an engineering submittal.
    Data
    For both queries and responses, the data is in sixteen bit (two bytes, one word) chunks. For
    each two byte word, the left most byte is the most significant. For each byte, the left most
    bit is the most significant.
    This portion of the message changes with each function code. See the detail that follows for
    each function for the specifics of this message component.
    Byte Count
    The number of bytes contained in the data portion of the message. This is used on both
    queries (reads) and responses.
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    Cyclical Redundancy Check (CRC)
    This portion of the message is used to prevent incorrect data from being used in the Master
    or Slave because of communication errors.
    Function Details
    Function 01 - Read Coil Status
    This function reads the state of one or more coils (MODBUS 0x references) in the slave
    (CMC Base Control Module). For the CMC, these coils represent the Discrete (Digital)
    Outputs, compressor operating state (see the Operator User Interface Status Bar for
    definition), any compressor Trip condition and any compressor Alarm condition. If the
    function returns a 1, the discrete output is on. If the function returns a 0, the discrete output
    is off. Broadcast is not supported. Refer to the table on the next page for MODBUS
    Absolute Addresses for each coil supported by the CMC-MODBUS Interface.
    Absolute
    Address
    (decimal)
    00187
    00188
    00189
    00190
    00191
    00192
    00193
    00194
    00195
    00196
    00197
    00198
    00199
    00200
    00201
    00202
    Relative
    Address
    (hex)
    00-BA
    00-BB
    00-BC
    00-BD
    00-BE
    00-BF
    00-C0
    00-C1
    00-C2
    00-C3
    00-C4
    00-C5
    00-C6
    00-C7
    00-C8
    00-C9
    Absolute
    Relative
    Address
    Address
    Coil Name - Read Only*
    (decimal)
    (hex)
    Digital Output, Channel 1 (J15-P7,8)
    00203
    00-CA
    Compressor State - Waiting
    Digital Output, Channel 2 (J15-P5,6)
    00204
    00-CB
    Compressor State - Coasting
    Digital Output, Channel 3 (J15-P3,4)
    00205
    00-CC
    Compressor State - Starting
    Digital Output, Channel 4 (J15-P1,2)
    00206
    00-CD
    Compressor State - Not Ready
    Digital Output, Channel 5 (J14-P7,8)
    00207
    00-CE
    Compressor State - Ready
    Digital Output, Channel 6 (J14-P5,6)
    00208
    00-CF
    Compressor State - Surge Unload
    Digital Output, Channel 7 (J14-P3,4)
    00209
    00-D0
    Compressor State - Autodual Unload
    Digital Output, Channel 8 (J14-P1,2)
    00210
    00-D1
    Compressor State - Unloading
    Digital Output, Channel 9 (J13-P7,8)
    00211
    00-D2
    Compressor State - Unloaded
    Digital Output, Channel 10 (J13-P5,6)
    00212
    00-D3
    Compressor State - Min load
    Digital Output, Channel 11 (J13-P3,4)
    00213
    00-D4
    Compressor State - Max load
    Digital Output, Channel 12 (J13-P1,2)
    00214
    00-D5
    Compressor State - Loading
    Digital Output, Channel 13 (J12-P7,8)
    00215
    00-D6
    Compressor State - Loaded
    Digital Output, Channel 14 (J12-P5,6)
    00216
    00-D7
    Compressor State - Full Load
    Digital Output, Channel 15 (J12-P3,4)
    00217
    00-D8
    Compressor State - Analog Input Failed
    Digital Output, Channel 16 (J12-P1,2)
    00218
    00-D9
    Any Compressor Trip
    00219
    00-DA
    Any Compressor Alarm
    NOTE: (J15-P7,8) is interpreted as Connector J15, Pins 7 and 8 on the Base Control Module. * IMPORTANT: These coils are defined as
    read only. If you decide to write to these coils, unexpected results could occur.
    Coil Name - Read Only*
    Example: Reading a Single Coil
    After reviewing the Electrical Schematic for your compressor, you determine that the digital
    output for the prelube pump is located on J12-P7,8 (Channel 13). From the table above, the
    Absolute Address is decimal 00199 (Relative Address is hexadecimal 00C6) for the output
    in question. Therefore, to read the state of the prelube pump output the following command
    is issued (the following data are presented in hexadecimal format):
    Device
    Address
    01
    Function
    Code
    01
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    Address
    Hi
    Lo
    00
    C6
    Number of
    Coils
    Hi
    Lo
    00
    01
    CRC
    Lo
    1D
    Hi
    F7
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    The response from this command is:
    Device
    Address
    01
    Function
    Code
    01
    Byte
    Count
    01
    CRC
    Data
    01
    Lo
    90
    Hi
    48
    The data (01) means that the discrete output is on, or the prelube pump is running.
    Example: Reading Multiple Coils
    To read all sixteen digital (discrete) outputs, the following command is sent:
    Device
    Address
    01
    Function
    Code
    01
    Address
    Hi
    Lo
    00
    BA
    Number of
    Coils
    Hi
    Lo
    00
    10
    CRC
    Lo
    1C
    Hi
    23
    where relative address 00-BA is for digital (discrete) output for Channel 1. The response
    from this command is:
    Device
    Address
    01
    Function
    Code
    01
    Byte
    Count
    02
    CRC
    Data
    04-10
    Lo
    BA
    Hi
    F0
    To determine the state of each output, review the Electrical Schematic for your compressor.
    For this example, you determine that the digital output for the prelube pump is located on
    J12-P7,8 (Channel 13) and the digital output for the remote trouble contact is J15-P3,4
    (Channel 3). The first hexadecimal data byte 04 (0000 0100 binary), represents the states
    of the first eight digital (discrete) outputs (8-1). Therefore, for this example 04 means that
    Channels 8, 7, 6, 5, 4, 2 and 1 are off and Channel 3 (compressor is in an alarm or trip
    condition) is on. For the next eight channels (16-9) the hexadecimal data byte 10 (0001
    0000 binary) means that Channels 16, 15, 14, 12, 11, 10 and 9 are off and Channel 13
    (prelube pump is running) is on. The following table graphically depicts this example:
    Response
    Byte 1
    Address
    8
    0
    C1
    7
    0
    C0
    6
    0
    BF
    5
    0
    BE
    4
    0
    BD
    3
    1
    BC
    2
    0
    BB
    1
    0
    BA
    Response
    Byte 2
    Address
    16
    0
    C9
    15
    0
    C8
    14
    0
    C7
    13
    1
    C6
    12
    0
    C5
    11
    0
    C4
    10
    0
    C3
    9
    0
    C2
    A bit response of 1 means that the output is on and a response of 0 means that the output
    is off.
    Function 02 - Read Input Status
    This function reads the state of one or more discrete inputs (MODBUS 1x references) in the
    slave (CMC Base Control Module). For the CMC, these inputs represent the Discrete
    (Digital) Inputs. If the function returns a 1, the input is on. If the function returns a 0, the
    input is off. Broadcast is not supported. Refer to the table on the next page for MODBUS
    Absolute Addresses for each discrete input supported by the CMC-MODBUS Interface.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    99
    CMC TECHNICAL REFERENCE MANUAL
    Absolute Address
    Relative Address
    Input Name - Read Only*
    (decimal)
    (hex)
    10171
    00-AA
    Digital Input, Channel 1 (J4-P2)
    10172
    00-AB
    Digital Input, Channel 2 (J4-P3)
    10173
    00-AC
    Digital Input, Channel 3 (J4-P4)
    10174
    00-AD
    Digital Input, Channel 4 (J4-P5)
    10175
    00-AE
    Digital Input, Channel 5 (J4-P6)
    10176
    00-AF
    Digital Input, Channel 6 (J4-P7)
    10177
    00-B0
    Digital Input, Channel 7 (J4-P8)
    10178
    00-B1
    Digital Input, Channel 8 (J4-P9)
    10179
    00-B2
    Digital Input, Channel 9 (J5-P2)
    10180
    00-B3
    Digital Input, Channel 10 (J5-P3)
    10181
    00-B4
    Digital Input, Channel 11 (J5-P4)
    10182
    00-B5
    Digital Input, Channel 12 (J5-P5)
    10183
    00-B6
    Digital Input, Channel 13 (J5-P6)
    10184
    00-B7
    Digital Input, Channel 14 (J5-P7)
    10185
    00-B8
    Digital Input, Channel 15 (J5-P8)
    10186
    00-B9
    Digital Input, Channel 16 (J5-P9)
    NOTE: (J4-P2) is interpreted as Connector J4, Pin 2 on the Base Control Module.
    * IMPORTANT: These Digital Inputs are defined as read only. If you decide to
    write to these Inputs, unexpected results could occur.
    Example: Read Single Discrete Input
    After reviewing the Electrical Schematic for your compressor, you determine that the digital
    input for emergency stop push button is located on J4-P5 (Channel 4). From the table
    above, the Absolute Address is decimal 10174 (Relative Address is hexadecimal 00AD) for
    the input in question. Therefore, to read the state of the emergency stop push button the
    following command is issued (the following data are presented in hexadecimal format):
    Device
    Address
    01
    Function
    Code
    02
    Address
    Hi
    Lo
    00
    AD
    Number of
    Digital Inputs
    Hi
    Lo
    00
    01
    CRC
    Lo
    28
    Hi
    2B
    The response from this command is:
    Device
    Address
    01
    Function
    Code
    02
    Byte
    Count
    01
    CRC
    Data
    01
    Lo
    60
    Hi
    48
    The data (01) means that the input is on, or the emergency stop push button is pressed.
    Example: Read Multiple Discrete Inputs
    The method for reading multiple Discrete Inputs is the same as reading multiple coils. See
    the example for “Reading Multiple Coils”.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    100
    CMC TECHNICAL REFERENCE MANUAL
    Function 03 - Read Holding Registers
    Reads the binary content of holding registers (MODBUS 4x references) in the slave (CMC
    Base Control Module). For the CMC, these holding registers contain the Analog Output
    values and Analog Alarm and Trip Setpoint values for all CMC inputs and outputs.
    Broadcast is not supported.
    The CMC is primarily a 32-bit floating-point microprocessor controller. And, since MODBUS
    is designed to be a 16-bit system, the CMC supports two methods for determining the value
    for each holding register (This also applies to Input Registers.)
    NOTE
    Since MODBUS is a 16-bit system, the programmer must get two 16-bit numbers and
    combine them into one 32-bit floating-point number.
    The first method uses two 16-bit integers to represent the integer and fraction part of the
    value. The second method uses one 32-bit IEEE floating point number. (NOTE: For those
    who would like to only get the 16-bit integer value, this will work well for most inputs;
    however, the CMC has some inputs, like vibration, that are typically less than one.
    Since the CMC has programmable analog and discrete inputs and outputs, the programmer
    must use the electrical schematic supplied with the contract to determine which function
    name and units of measure are associated with each input and output.
    Refer to the table below for MODBUS Absolute Addresses for each Holding Register
    supported by the CMC-MODBUS Interface.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    101
    CMC TECHNICAL REFERENCE MANUAL
    Holding Register Name - Read/Write
    Analog Output, Channel 1 (J3-P1,3)
    Analog Output, Channel 2 (J3-P4,6)
    Analog Output, Channel 3 (J3-P7,9)
    Analog Output, Channel 4 (J3-P10,12)
    Analog Input, Channel 1 (J2-P1,3) - High Trip Setpoint
    Analog Input, Channel 1 (J2-P1,3) - High Alarm Setpoint
    Analog Input, Channel 1 (J2-P1,3) - Low Alarm Setpoint
    Analog Input, Channel 1 (J2-P1,3) - Low Trip Setpoint
    Analog Input, Channel 2 (J2-P5,7) - High Trip Setpoint
    Analog Input, Channel 2 (J2-P5,7) - High Alarm Setpoint
    Analog Input, Channel 2 (J2-P5,7) - Low Alarm Setpoint
    Analog Input, Channel 2 (J2-P5,7) - Low Trip Setpoint
    Analog Input, Channel 3 (J1-P1) - High Trip Setpoint
    Analog Input, Channel 3 (J1-P1) - High Alarm Setpoint
    Analog Input, Channel 3 (J1-P1) - Low Alarm Setpoint
    Analog Input, Channel 3 (J1-P1) - Low Trip Setpoint
    Analog Input, Channel 4 (J1-P4) - High Trip Setpoint
    Analog Input, Channel 4 (J1-P4) - High Alarm Setpoint
    Analog Input, Channel 4 (J1-P4) - Low Alarm Setpoint
    Analog Input, Channel 4 (J1-P4) - Low Trip Setpoint
    Analog Input, Channel 5 (J1-P5) - High Trip Setpoint
    Analog Input, Channel 5 (J1-P5) - High Alarm Setpoint
    Analog Input, Channel 5 (J1-P5) - Low Alarm Setpoint
    Analog Input, Channel 5 (J1-P5) - Low Trip Setpoint
    Analog Input, Channel 6 (J1-P8) - High Trip Setpoint
    Analog Input, Channel 6 (J1-P8) - High Alarm Setpoint
    Analog Input, Channel 6 (J1-P8) - Low Alarm Setpoint
    Analog Input, Channel 6 (J1-P8) - Low Trip Setpoint
    Analog Input, Channel 7 (J1-P9) - High Trip Setpoint
    Analog Input, Channel 7 (J1-P9) - High Alarm Setpoint
    Analog Input, Channel 7 (J1-P9) - Low Alarm Setpoint
    Analog Input, Channel 7 (J1-P9) - Low Trip Setpoint
    Analog Input, Channel 8 (J1-P12) - High Trip Setpoint
    Analog Input, Channel 8 (J1-P12) - High Alarm Setpoint
    Analog Input, Channel 8 (J1-P12) - Low Alarm Setpoint
    Analog Input, Channel 8 (J1-P12) - Low Trip Setpoint
    Analog Input, Channel 9 (J1-P13) - High Trip Setpoint
    Analog Input, Channel 9 (J1-P13) - High Alarm Setpoint
    Analog Input, Channel 9 (J1-P13) - Low Alarm Setpoint
    Analog Input, Channel 9 (J1-P13) - Low Trip Setpoint
    Analog Input, Channel 10 (J1-P16) - High Trip Setpoint
    Analog Input, Channel 10 (J1-P16) - High Alarm Setpoint
    Analog Input, Channel 10 (J1-P16) - Low Alarm Setpoint
    Analog Input, Channel 10 (J1-P16) - Low Trip Setpoint
    Analog Input, Channel 11 (J1-P17) - High Trip Setpoint
    Analog Input, Channel 11 (J1-P17) - High Alarm Setpoint
    Analog Input, Channel 11 (J1-P17) - Low Alarm Setpoint
    Analog Input, Channel 11 (J1-P17) - Low Trip Setpoint
    Analog Input, Channel 12 (J1-P20) - High Trip Setpoint
    Analog Input, Channel 12 (J1-P20) - High Alarm Setpoint
    Analog Input, Channel 12 (J1-P20) - Low Alarm Setpoint
    Analog Input, Channel 12 (J1-P20) - Low Trip Setpoint
    Analog Input, Channel 13 (J1-P21) - High Trip Setpoint
    Analog Input, Channel 13 (J1-P21) - High Alarm Setpoint
    Analog Input, Channel 13 (J1-P21) - Low Alarm Setpoint
    Analog Input, Channel 13 (J1-P21) - Low Trip Setpoint
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Signed
    16 Bit Exponent
    Absolute
    Relative
    Address
    Address
    (Decimal)
    (hex)
    40053
    00-34
    40055
    00-36
    40057
    00-38
    40059
    00-3A
    40061
    00-3C
    40063
    00-3E
    40065
    00-40
    40067
    00-42
    40069
    00-44
    40071
    00-46
    40073
    00-48
    40075
    00-4A
    40077
    00-4C
    40079
    00-4E
    40081
    00-50
    40083
    00-52
    40085
    00-54
    40087
    00-56
    40089
    00-58
    40091
    00-5A
    40093
    00-5C
    40095
    00-5E
    40097
    00-60
    40099
    00-62
    40101
    00-64
    40103
    00-66
    40105
    00-68
    40107
    00-6A
    40109
    00-6C
    40111
    00-6E
    40113
    00-70
    40115
    00-72
    40117
    00-74
    40119
    00-76
    40121
    00-78
    40123
    00-7A
    40125
    00-7C
    40127
    00-7E
    40129
    00-80
    40131
    00-82
    40133
    00-84
    40135
    00-86
    40137
    00-88
    40139
    00-8A
    40141
    00-8C
    40143
    00-8E
    40145
    00-90
    40147
    00-92
    40149
    00-94
    40151
    00-96
    40153
    00-98
    40155
    00-9A
    40157
    00-9C
    40159
    00-9E
    40161
    00-A0
    40163
    00-A2
    Unsigned
    16 Bit Fraction
    Absolute
    Relative
    Address
    Address
    (Decimal)
    (hex)
    40054
    00-35
    40056
    00-37
    40058
    00-39
    40060
    00-3B
    40062
    00-3D
    40064
    00-3F
    40066
    00-41
    40068
    00-43
    40070
    00-45
    40072
    00-47
    40074
    00-49
    40076
    00-4B
    40078
    00-4D
    40080
    00-4F
    40082
    00-51
    40084
    00-53
    40086
    00-55
    40088
    00-57
    40090
    00-59
    40092
    00-5B
    40094
    00-5D
    40096
    00-5F
    40098
    00-61
    40100
    00-63
    40102
    00-65
    40104
    00-67
    40106
    00-69
    40108
    00-6B
    40110
    00-6D
    40112
    00-6F
    40114
    00-71
    40116
    00-73
    40118
    00-75
    40120
    00-77
    40122
    00-79
    40124
    00-7B
    40126
    00-7D
    40128
    00-7F
    40130
    00-81
    40132
    00-83
    40134
    00-85
    40136
    00-87
    40138
    00-89
    40140
    00-8B
    40142
    00-8D
    40144
    00-8F
    40146
    00-91
    40148
    00-93
    40150
    00-95
    40152
    00-97
    40154
    00-99
    40156
    00-9B
    40158
    00-9D
    40160
    00-9F
    40162
    00-A1
    40164
    00-A3
    Signed
    IEEE 32-Bit Float
    Absolute
    Relative
    Address
    Address
    (Decimal)
    (hex)
    43053
    0B-EC
    43055
    0B-EE
    43057
    0B-F0
    43059
    0B-F2
    43061
    0B-F4
    43063
    0B-F6
    43065
    0B-F8
    43067
    0B-FA
    43069
    0B-FC
    43071
    0B-FE
    43073
    0C-00
    43075
    0C-02
    43077
    0C-04
    43079
    0C-06
    43081
    0C-08
    43083
    0C-0A
    43085
    0C-0C
    43087
    0C-0E
    43089
    0C-10
    43091
    0C-12
    43093
    0C-14
    43095
    0C-16
    43097
    0C-18
    43099
    0C-1A
    43101
    0C-1C
    43103
    0C-1E
    43105
    0C-20
    43107
    0C-22
    43109
    0C-24
    43111
    0C-26
    43113
    0C-28
    43115
    0C-2A
    43117
    0C-2C
    43119
    0C-2E
    43121
    0C-30
    43123
    0C-32
    43125
    0C-34
    43127
    0C-36
    43129
    0C-38
    43131
    0C-3A
    43133
    0C-3C
    43135
    0C-3E
    43137
    0C-40
    43139
    0C-42
    43141
    0C-44
    43143
    0C-46
    43145
    0C-48
    43147
    0C-4A
    43149
    0C-4C
    43151
    0C-4E
    43153
    0C-50
    43155
    0C-52
    43157
    0C-54
    43159
    0C-56
    43161
    0C-58
    43163
    0C-5A
    102
    CMC TECHNICAL REFERENCE MANUAL
    Holding Register Name - Read/Write
    Analog Input, Channel 14 (J1-P24) - High Trip Setpoint
    Analog Input, Channel 14 (J1-P24) - High Alarm Setpoint
    Analog Input, Channel 14 (J1-P24) - Low Alarm Setpoint
    Analog Input, Channel 14 (J1-P24) - Low Trip Setpoint
    Analog Input, Channel 15 (J1-P25) - High Trip Setpoint
    Analog Input, Channel 15 (J1-P25) - High Alarm Setpoint
    Analog Input, Channel 15 (J1-P25) - Low Alarm Setpoint
    Analog Input, Channel 15 (J1-P25) - Low Trip Setpoint
    Analog Input, Channel 16 (J1-P28) - High Trip Setpoint
    Analog Input, Channel 16 (J1-P28) - High Alarm Setpoint
    Analog Input, Channel 16 (J1-P28) - Low Alarm Setpoint
    Analog Input, Channel 16 (J1-P28) - Low Trip Setpoint
    Analog Input, Channel 17 (J1-P29) - High Trip Setpoint
    Analog Input, Channel 17 (J1-P29) - High Alarm Setpoint
    Analog Input, Channel 17 (J1-P29) - Low Alarm Setpoint
    Analog Input, Channel 17 (J1-P29) - Low Trip Setpoint
    Analog Input, Channel 18 (J1-P32) - High Trip Setpoint
    Analog Input, Channel 18 (J1-P32) - High Alarm Setpoint
    Analog Input, Channel 18 (J1-P32) - Low Alarm Setpoint
    Analog Input, Channel 18 (J1-P32) - Low Trip Setpoint
    Analog Input, Channel 19 (J1-P33) - High Trip Setpoint
    Analog Input, Channel 19 (J1-P33) - High Alarm Setpoint
    Analog Input, Channel 19 (J1-P33) - Low Alarm Setpoint
    Analog Input, Channel 19 (J1-P33) - Low Trip Setpoint
    Analog Input, Channel 20 (J1-P36) - High Trip Setpoint
    Analog Input, Channel 20 (J1-P36) - High Alarm Setpoint
    Analog Input, Channel 20 (J1-P36) - Low Alarm Setpoint
    Analog Input, Channel 20 (J1-P36) - Low Trip Setpoint
    Analog Input, Channel 21 (J1-P37) - High Trip Setpoint
    Analog Input, Channel 21 (J1-P37) - High Alarm Setpoint
    Analog Input, Channel 21 (J1-P37) - Low Alarm Setpoint
    Analog Input, Channel 21 (J1-P37) - Low Trip Setpoint
    Analog Input, Channel 22 (J1-P40) - High Trip Setpoint
    Analog Input, Channel 22 (J1-P40) - High Alarm Setpoint
    Analog Input, Channel 22 (J1-P40) - Low Alarm Setpoint
    Analog Input, Channel 22 (J1-P40) - Low Trip Setpoint
    Analog Input, Channel 23 (J1-P41) - High Trip Setpoint
    Analog Input, Channel 23 (J1-P41) - High Alarm Setpoint
    Analog Input, Channel 23 (J1-P41) - Low Alarm Setpoint
    Analog Input, Channel 23 (J1-P41) - Low Trip Setpoint
    Motor Current
    User Pressure Setpoint
    MinLoad (Throttle Limit, TL)
    MaxLoad (High Load Limit, HLL)
    Autodual Reload Percent
    Autodual Unload Point
    Autodual Unload Timer
    Pressure Setpoint Ramp Rate
    Inlet Valve Unload Position
    Start Timer
    CT Ratio
    Power On Hours
    Running Hours
    Loaded Hours
    Number of Starts
    Signed
    16 Bit Exponent
    Absolute
    Relative
    Address
    Address
    (Decimal)
    (hex)
    40165
    00-A4
    40167
    00-A6
    40169
    00-A8
    40171
    00-AA
    40173
    00-AC
    40175
    00-AE
    40177
    00-B0
    40179
    00-B2
    40181
    00-B4
    40183
    00-B6
    40185
    00-B8
    40187
    00-BA
    40189
    00-BC
    40191
    00-BE
    40193
    00-C0
    40195
    00-C2
    40197
    00-C4
    40199
    00-C6
    40201
    00-C8
    40203
    00-CA
    40205
    00-CC
    40207
    00-CE
    40209
    00-D0
    40211
    00-D2
    40213
    00-D4
    40215
    00-D6
    40217
    00-D8
    40219
    00-DA
    40221
    00-DC
    40223
    00-DE
    40225
    00-E0
    40227
    00-E2
    40229
    00-E4
    40231
    00-E6
    40233
    00-E8
    40235
    00-EA
    40237
    00-EC
    40239
    00-EE
    40241
    00-F0
    40243
    00-F2
    40267
    01-0A
    40269
    01-0C
    40271
    01-0E
    40273
    01-10
    40275
    01-12
    40277
    01-14
    40279
    01-16
    40281
    01-18
    40283
    01-1A
    40285
    01-1C
    40287
    01-1E
    40297
    01-28
    40299
    01-2A
    40301
    01-2C
    40303
    01-2E
    Unsigned
    16 Bit Fraction
    Absolute
    Relative
    Address
    Address
    (Decimal)
    (hex)
    40166
    00-A5
    40168
    00-A7
    40170
    00-A9
    40172
    00-AB
    40174
    00-AD
    40176
    00-AF
    40178
    00-B1
    40180
    00-B3
    40182
    00-B5
    40184
    00-B7
    40186
    00-B9
    40188
    00-BB
    40190
    00-BD
    40192
    00-BF
    40194
    00-C1
    40196
    00-C3
    40198
    00-C5
    40200
    00-C7
    40202
    00-C9
    40204
    00-CB
    40206
    00-CD
    40208
    00-CF
    40210
    00-D1
    40212
    00-D3
    40214
    00-D5
    40216
    00-D7
    40218
    00-D9
    40220
    00-DB
    40222
    00-DD
    40224
    00-DF
    40226
    00-E1
    40228
    00-E3
    40230
    00-E5
    40232
    00-E7
    40234
    00-E9
    40236
    00-EB
    40238
    00-ED
    40240
    00-EF
    40242
    00-F1
    40244
    00-F3
    40268
    01-0B
    40270
    01-0D
    40272
    01-0F
    40274
    01-11
    40276
    01-13
    40278
    01-15
    40280
    01-17
    40282
    01-19
    40284
    01-1B
    40286
    01-1D
    40288
    01-1F
    40298
    01-29
    40300
    01-2B
    40302
    01-2D
    40304
    01-2F
    Signed
    IEEE 32-Bit Float
    Absolute
    Relative
    Address
    Address
    (Decimal)
    (hex)
    43165
    0C-5C
    43167
    0C-5E
    43169
    0C-60
    43171
    0C-62
    43173
    0C-64
    43175
    0C-66
    43177
    0C-68
    43179
    0C-6A
    43181
    0C-6C
    43183
    0C-6E
    43185
    0C-70
    43187
    0C-72
    43189
    0C-74
    43191
    0C-76
    43193
    0C-78
    43195
    0C-7A
    43197
    0C-7C
    43199
    0C-7E
    43201
    0C-80
    43203
    0C-82
    43205
    0C-84
    43207
    0C-86
    43209
    0C-88
    43211
    0C-8A
    43213
    0C-8C
    43215
    0C-8E
    43217
    0C-90
    43219
    0C-92
    43221
    0C-94
    43223
    0C-96
    43225
    0C-98
    43227
    0C-9A
    43229
    0C-9C
    43231
    0C-9E
    43233
    0C-A0
    43235
    0C-A2
    43237
    0C-A4
    43239
    0C-A6
    43241
    0C-A8
    43243
    0C-AA
    43267
    0C-C2
    43269
    0C-C4
    43271
    0C-C6
    43273
    0C-C8
    43275
    0C-CA
    43277
    0C-CC
    43279
    0C-CE
    43281
    0C-D0
    43283
    0C-D2
    43285
    0C-D4
    43287
    0C-D6
    43297
    0C-E0
    43299
    0C-E2
    43301
    0C-E4
    43303
    0C-E6
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    Signed
    16 Bit Exponent
    Absolute
    Relative
    Holding Register Name - Read/Write
    Address
    Address
    (Decimal)
    (hex)
    Inlet Valve, MaxLoad, Proportional Constant
    40313
    01-38
    Inlet Valve, MaxLoad, Integral Constant
    40315
    01-3A
    Inlet Valve, MaxLoad, Derivative Constant
    40317
    01-3C
    Inlet Valve, MinLoad, Proportional Constant
    40319
    01-3E
    Inlet Valve, MinLoad, Integral Constant
    40321
    01-40
    Inlet Valve, MinLoad, Derivative Constant
    40323
    01-42
    Inlet Valve, Pressure, Proportional Constant
    40325
    01-44
    Inlet Valve, Pressure, Integral Constant
    40327
    01-46
    Inlet Valve, Pressure, Derivative Constant
    40329
    01-48
    Bypass Valve, Pressure, Proportional Constant
    40331
    01-4A
    Bypass Valve, Pressure, Integral Constant
    40333
    01-4C
    Bypass Valve, Pressure, Derivative Constant
    40335
    01-4E
    Compressor Control Mode; 1=Modulate, 2=Autodual
    40339
    01-52
    NOTE: (J1-P1) is interpreted as Connector J1, Pin 1 on the Base Control Module.
    Unsigned
    16 Bit Fraction
    Absolute
    Relative
    Address
    Address
    (Decimal)
    (hex)
    40314
    01-39
    40316
    01-3B
    40318
    01-3D
    40320
    01-3F
    40322
    01-41
    40324
    01-43
    40326
    01-45
    40328
    01-47
    40330
    01-49
    40332
    01-4B
    40334
    01-4D
    40336
    01-4F
    40340
    01-53
    Signed
    IEEE 32-Bit Float
    Absolute
    Relative
    Address
    Address
    (Decimal)
    (hex)
    43313
    0C-F0
    43315
    0C-F2
    43317
    0C-F4
    43319
    0C-F6
    43321
    0C-F8
    43323
    0C-FA
    43325
    0C-FC
    43327
    0C-FE
    43329
    0D-00
    43331
    0D-02
    43333
    0D-04
    43335
    0D-06
    43339
    0D-0A
    Example: See example for Function 04.
    Function 04 - Read Input Registers
    Reads the binary content of input registers (MODBUS 3x references) in the slave (CMC
    Base Control Module). For the CMC, these input registers refer to the Analog Input values.
    Broadcast is not supported.
    The CMC is primarily a 32-bit floating-point microprocessor controller. And, since MODBUS
    is designed to be a 16-bit system, the CMC supports two methods for determining the value
    for each holding register. (This also applies to Input Registers.) The first method uses two
    16-bit integers to represent the integer and fraction part of the value. The second method
    uses one 32-bit IEEE floating point number.
    NOTE
    Since MODBUS is a 16-bit system, the programmer must get two 16-bit numbers and
    combine them into one 32-bit floating-point number.
    For those who would like to only get the 16-bit integer value, this will work well for most
    inputs; however, the CMC has some inputs, like vibration, that are typically less than one.
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    Signed
    Unsigned
    Signed
    16-Bit Integer
    16-Bit Fraction
    IEEE 32-Bit Float
    Absolute
    Relative
    Absolute
    Relative
    Absolute
    Relative
    Input Register Name - Read Only*
    Address
    Address
    Address
    Address
    Address
    Address
    (Decimal)
    (hex)
    (Decimal)
    (hex)
    (Decimal)
    (hex)
    Analog Input, Channel 1 (J2-P1,3)
    30003
    00-02
    30004
    00-03
    33003
    0B-BA
    Analog Input, Channel 2 (J2-P5,7)
    30005
    00-04
    30006
    00-05
    33005
    0B-BC
    Analog Input, Channel 3 (J1-P1)
    30007
    00-06
    30008
    00-07
    33007
    0B-BE
    Analog Input, Channel 4 (J1-P4)
    30009
    00-08
    30010
    00-09
    33009
    0B-C0
    Analog Input, Channel 5 (J1-P5)
    30011
    00-0A
    30012
    00-0B
    33011
    0B-C2
    Analog Input, Channel 6 (J1-P8)
    30013
    00-0C
    30014
    00-0D
    33013
    0B-C4
    Analog Input, Channel 7 (J1-P9)
    30015
    00-0E
    30016
    00-0F
    33015
    0B-C6
    Analog Input, Channel 8 (J1-P12)
    30017
    00-10
    30018
    00-11
    33017
    0B-C8
    Analog Input, Channel 9 (J1-P13)
    30019
    00-12
    30020
    00-13
    33019
    0B-CA
    Analog Input, Channel 10 (J1-P16)
    30021
    00-14
    30022
    00-15
    33021
    0B-CC
    Analog Input, Channel 11 (J1-P17)
    30023
    00-16
    30024
    00-17
    33023
    0B-CE
    Analog Input, Channel 12 (J1-P20)
    30025
    00-18
    30026
    00-19
    33025
    0B-D0
    Analog Input, Channel 13 (J1-P21)
    30027
    00-1A
    30028
    00-1B
    33027
    0B-D2
    Analog Input, Channel 14 (J1-P24)
    30029
    00-1C
    30030
    00-1D
    33029
    0B-D4
    Analog Input, Channel 15 (J1-P25)
    30031
    00-1E
    30032
    00-1F
    33031
    0B-D6
    Analog Input, Channel 16 (J1-P28)
    30033
    00-20
    30034
    00-21
    33033
    0B-D8
    Analog Input, Channel 17 (J1-P29)
    30035
    00-22
    30036
    00-23
    33035
    0B-DA
    Analog Input, Channel 18 (J1-P32)
    30037
    00-24
    30038
    00-25
    33037
    0B-DC
    Analog Input, Channel 19 (J1-P33)
    30039
    00-26
    30040
    00-27
    33039
    0B-DE
    Analog Input, Channel 20 (J1-P36)
    30041
    00-28
    30042
    00-29
    33041
    0B-E0
    Analog Input, Channel 21 (J1-P37)
    30043
    00-2A
    30044
    00-2B
    33043
    0B-E2
    Analog Input, Channel 22 (J1-P40)
    30045
    00-2C
    30046
    00-2D
    33045
    0B-E4
    Analog Input, Channel 23 (J1-P41)
    30047
    00-2E
    30048
    00-2F
    33047
    0B-E6
    CT Input (J9-P1,2)
    30049
    00-30
    30050
    00-31
    33049
    0B-E8
    NOTE: (J1-P1) is interpreted as Connector J1, Pin 1 on the Base Control Module. * IMPORTANT: These Input Registers are defined as read only. If
    you decide to write to these Input Registers, unexpected results could occur.
    Example: Read Single Channel 16-Bit Integer and Fraction
    After reviewing the Electrical Schematic for your compressor, you determine that the analog
    input for System Pressure is located on J1-P1 (Channel 3). From the table above, the
    Absolute Address is decimal 30007 (Relative Address is hexadecimal 0006) for the input in
    question. Therefore, to read the 16 Bit Integer and 16 Bit Fraction for System Pressure the
    following command is issued (the following data are presented in hexadecimal format):
    Device
    Address
    01
    Function
    Code
    04
    Number of
    Registers
    Hi
    Lo
    00
    02
    Address
    Hi
    Lo
    00
    06
    CRC
    Lo
    91
    Hi
    CA
    The response from this command is:
    Data
    Device
    Address
    01
    Function
    Code
    04
    Byte
    Count
    04
    Reg-1
    Hi
    00
    Reg-2
    Lo
    64
    Hi
    13
    CRC
    Lo
    4E
    Lo
    37
    Hi
    5F
    Register 1 is the Integer portion of the System Pressure or (0064h, 100 decimal). Register 2
    is the Fraction portion of the System Pressure or (134Eh, 4942 decimal). Each fraction has
    a range between 0 and 9999. So the System Pressure, expressed as a floating point
    number is 100.4942 psi.
    Example: Read Single Channel IEEE 32-Bit Floating Point Number
    To continue with the example, when you decide to get the System Pressure as an IEEE 32
    Bit floating point number you must issue the following command:
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    Device
    Address
    01
    Function
    Code
    04
    Number of
    Registers
    Hi
    Lo
    00
    02
    Address
    Hi
    Lo
    0B
    BE
    CRC
    Lo
    13
    Hi
    CB
    The response from this command is:
    Data
    Device
    Address
    01
    Function
    Code
    04
    Byte
    Count
    04
    Reg-1
    Hi
    42
    Reg-2
    Lo
    DC
    Hi
    D4
    CRC
    Lo
    C6
    Lo
    F1
    Hi
    54
    So the System Pressure, expressed as a floating point number is 110.4155731201 psi.
    IEEE floating-point numbers are represented in 32 bits as shown below.
    31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
    exponent
    9
    8
    7
    6
    5
    4
    3
    2
    1
    0
    mantissa
    sign
    Convert hexadecimal registers 1 and 2 (Reg-1, Reg-2) into decimal values ...
    Register
    1
    1
    2
    2
    Byte
    Hi
    Lo
    Hi
    Lo
    Symbol
    R1HB
    R1LB
    R2HB
    R2LB
    Hex
    42
    DC
    D4
    C6
    Decimal
    66
    220
    212
    198
    Determine the sign (positive = 0 or negative = 1) ...
    Sign = (R1HB And 128) / 128, where And is defined as a bit-wise And
    Sign = (66 And 128) / 128 = 0
    Determine the exponent ...
    Exponent = ((R1HB And 127) ∗ 2) + INT(R1LB / 128), where INT is defined as INTEGER
    Exponent = ((66 And 127) ∗ 2) + INT(220/128) = 133
    Determine the mantissa...
    Mantissa = ((((R1LB And 127) ∗ 256) + R2HB) ∗ 256) + R2LB
    Mantissa = ((((220 And 127) ∗ 256) + 212) ∗ 256) + 198 = 6083782
    Putting the 32 bit IEEE value together...
    Value = (-1sign) ∗ (2(exponent - 127)) ∗ ((Mantissa ∗ 2-23) + 1)
    Value = (-10) ∗ (2(133- 127)) ∗ ((6083782 ∗ 2-23) + 1) = 110.4155731201
    NOTE
    When Sign = Exponent = Mantissa = 0, Value = 0. This is a special case for the
    above equation.
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    Example: Read Multiple Channels
    The procedure for reading multiple channels is the same as reading a single channel with
    the exception of requesting more data. NOTE: You must read a contiguous group of
    registers (channels) for a single command.
    Function 05 - Force Single Coil
    Forces a single coil (MODBUS 0x references) to either ON or OFF. When broadcast, the
    function forces the same coil reference in all attached slaves. Refer to the table below for
    MODBUS Absolute Addresses for each coil supported by the CMC-MODBUS Interface.
    NOTE
    The Force Single Coil command will override the CMC’s current state. The forced
    state will remain valid until the CMC next solves the coil. The coil will remain forced if
    it is not programmed in the CMC logic.
    CAUTION
    For all of the following Remote Coils, the compressor’s REMOTE
    COMMUNICATIONS DISABLED/ENABLED selector switch must be in the ENABLED
    position for these commands to execute. When DISABLED, the CMC ignores (there
    is no exception response) these coils being forced ON or OFF.
    Absolute
    Address
    (decimal)
    00221
    00222
    00223
    00224
    00225
    00226
    Relative
    Address
    (hex)
    00-DC
    00-DD
    00-DE
    00-DF
    00-E0
    00-E1
    Coil Name - Write Only
    Remote Horn Silence (Acknowledge)
    Remote Reset
    Remote Load
    Remote Unload
    Remote Start
    Remote Stop
    Example: Forcing a Coil
    For all MODBUS devices, a value of FF 00 hex requests the coil to be ON. A value of 00 00
    requests it to be OFF. All other values are illegal and will not affect the coil. NOTE: For the
    CMC, forcing the above listed coils OFF is not meaningful because the default state of each
    of the above coils is OFF. When using these commands, they should be sent once
    (momentary) and the CMC will execute the commands. To remotely reset the compressor,
    the following command is issued:
    Device
    Address
    01
    Function
    Code
    05
    Address
    Hi
    Lo
    00
    DD
    Forced
    Data
    Hi
    FF
    CRC
    Lo
    00
    Lo
    1C
    Hi
    00
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    The response from this command is identical to the command sent:
    Device
    Address
    01
    Function
    Code
    05
    Address
    Hi
    Lo
    00
    DD
    Number of
    Registers
    Hi
    Lo
    FF
    00
    CRC
    Lo
    1C
    Hi
    00
    Function 06 - Preset Single Register
    Presets a value into a single holding register (MODBUS 4x reference). When broadcast, the
    function presets the same register reference in all attached slaves. Refer to the table for the
    Holding Register list for the MODBUS Absolute Addresses supported by the CMCMODBUS Interface.
    NOTE
    The Preset Single Register command will override the CMC’s current state. The
    preset value will remain valid in the register until the CMC logic next solves the
    register contents. The register's value will remain if it is not programmed in the
    controller's logic.
    CAUTION
    This function can only set a single 16-bit holding register. Since the CMC
    operates with 32-bit values, you must use Function 16 (10 Hex) - Preset Multiple
    Registers for setting the 32-bit IEEE register values. Also, you may not set the 16-bit
    fraction without its 16-bit integer. Therefore, you must use the Preset Multiple
    Registers function to send this 32-bit pair. See the examples that follow for
    Function 16.
    CAUTION
    The position of the REMOTE COMMUNICATIONS DISABLED/ENABLED
    selector switch is NOT considered when forcing coils or writing registers to the CMC.
    Reads and Writes are always enabled. Repeatedly writing a value to a register or
    forcing a coil without regard to the position of the switch can effectively disable a local
    write. Please use caution when writing registers or forcing coils. The REMOTE
    COMMUNICATIONS DISABLED/ENABLED selector switch is typically located on the
    front door of the Compressor’s Control Panel.
    Example: Presetting a Single Register (16-bit) Integer
    To change the integer value for the User Pressure Setpoint (absolute address 40269,
    relative address 01-0C) to 100 (00-64 hex) psi, send the following command...
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    Device
    Address
    01
    Function
    Code
    06
    Address
    Hi
    Lo
    01
    0C
    Register
    Value
    Hi
    Lo
    00
    64
    CRC
    Lo
    49
    Hi
    DE
    The response from this command is identical to the command sent:
    Device
    Address
    01
    Function
    Code
    06
    Address
    Hi
    Lo
    01
    0C
    Register
    Value
    Hi
    Lo
    00
    64
    CRC
    Lo
    49
    Hi
    DE
    Function 15 (0F Hex) - Force Multiple Coils
    Forces each coil (MODBUS 0x reference) in a series of contiguous coils to either ON or
    OFF. When broadcast, the function forces the same coil references in all attached slaves
    (CMC Base Control Modules). Refer to the table for the Coil list for the MODBUS Absolute
    Addresses supported by the CMC-MODBUS Interface.
    NOTE
    The Force Multiple Coils command will override the CMC’s current state. The forced
    state will remain valid until the CMC next solves the coil. The coil will remain forced if
    it is not programmed in the controller's logic.
    CAUTION
    The position of the REMOTE COMMUNICATIONS DISABLED/ENABLED
    selector switch is NOT considered when forcing coils or writing registers to the CMC.
    Reads and Writes are always enabled. Repeatedly writing a value to a register or
    forcing a coil without regard to the position of the switch can effectively disable a local
    write. Please use caution when writing registers or forcing coils. The REMOTE
    COMMUNICATIONS DISABLED/ENABLED selector switch is typically located on the
    front door of the Compressor’s Control Panel.
    Example: Forcing Multiple Coils
    To force a reset (absolute address 00222, relative address DD) and start (absolute address
    00225, relative address E0) of the compressor the following command is sent...
    Device
    Address
    01
    Function
    Code
    0F
    Address
    Hi
    Lo
    00
    DD
    Number of
    Coils
    Hi
    Lo
    00
    04
    Number
    of Data
    Bytes
    01
    Coil
    Data
    Lo
    09
    CRC
    Lo
    12
    Hi
    83
    The number of contiguous coils is four (00225, 00224, 00223 and 00222). The number of
    data bytes is one because we can set up to eight coils in a single byte. The coil data is nine
    22204796 Rev. B, Version 3.10
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    because we want to set the first bit and fourth bit in the byte (0000-1001, the bytes are
    numbered right to left). All bits not used are padded with zero.
    The response from this command is similar to the command sent except that the number of
    data bytes and the coil data themselves are not echoed:
    Device
    Address
    01
    Function
    Code
    0F
    Address
    Hi
    Lo
    00
    DD
    Number of
    Coils
    Hi
    Lo
    00
    04
    CRC
    Lo
    Hi
    C4
    32
    Function 16 (10 Hex) - Preset Multiple Registers
    Presets values into a sequence of contiguous holding registers (MODBUS 4x references).
    When broadcast, the function presets the same register references in all attached slaves
    (CMC Base Control Modules). Refer to the table for the Input Register list for the MODBUS
    Absolute Addresses supported by the CMC-MODBUS Interface.
    NOTE
    The Preset Multiple Registers command will override the CMC’s current state. The
    forced state will remain valid until the CMC next solves the register. The register will
    remain forced if it is not programmed in the controller's logic.
    CAUTION
    The position of the REMOTE COMMUNICATIONS DISABLED/ENABLED
    selector switch is NOT considered when forcing coils or writing registers to the CMC.
    Reads and Writes are always enabled. Repeatedly writing a value to a register or
    forcing a coil without regard to the position of the switch can effectively disable a local
    write. Please use caution when writing registers or forcing coils. The REMOTE
    COMMUNICATIONS DISABLED/ENABLED selector switch is typically located on the
    front door of the Compressor’s Control Panel.
    Example: Presetting Holding Registers for 32-bit Values
    The difficulty in setting 32-bit values is determining the four data bytes for the number you
    want to send. The process required is...
    1.
    Determine the sign (positive = 0 or negative = 1). This is the first bit.
    2.
    Divide the decimal value by 2 until the result is less than 2, but greater than 1. Count
    the number of iterations required. Add 127 to the number of iterations. This result is the
    exponent. Convert this result to binary. These are the next eight bits.
    3.
    From the result obtained from step 2, subtract 1. Then, multiply this result by 2. If the
    result is less than 1, then the value of the first mantissa bit is 0. Otherwise, the
    mantissa bit is 1. If the result is greater than or equal to 1, then subtract 1 from the
    result and proceed with step 3 until the result is 0 or you have gone through this
    process 23 times.
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    4.
    Combine all 32 bits from the steps above and convert this value to hexadecimal. These
    32 bits are the 4 hexadecimal data bytes needed for the command.
    As an example, we will start with the decimal value
    of 105.4.
    1. Since this is a positive number, the first bit is 0.
    2. Determine the exponent bits by ...
    It took us six iterations to get the result to a number
    that is less than two and greater than or equal to one.
    Now, we must add 127 for an exponent of 133.
    Converting this to binary, the next eight bits are
    represented as 10000101.
    Iteration
    1
    2
    3
    4
    5
    6
    Iteration
    3. Determine the mantissa bits by
    From the table at right, 0100101100110011001100
    represent the next 23 bits.
    4. Combining the bits in sign, exponent and then
    mantissa order ...
    0100-0010-1101-0010-1100-1100-1100-1100
    This converts to 42-D2-CC-CC in hexadecimal.
    To change the holding registers for user pressure
    setpoint (for 32 bit IEEE floating point numbers the
    absolute address is 43269, relative address 0C-C4) to
    105.4, issue the following command...
    Device
    Address
    01
    Function
    Code
    10
    Address
    Hi
    Lo
    0C
    C4
    Number of
    Registers
    Hi
    Lo
    00
    02
    Number
    of Data
    Bytes
    04
    Decimal
    105.40000
    52.70000
    26.35000
    13.17500
    6.58750
    3.29375
    Data Bytes for
    Register #1
    Hi
    Lo
    42
    D2
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    Decimal
    1.646875
    1.29375
    0.5875
    1.175
    0.35
    0.7
    1.4
    0.8
    1.6
    1.2
    0.4
    0.8
    1.6
    1.2
    0.4
    0.8
    1.6
    1.2
    0.4
    0.8
    1.6
    1.2
    0.4
    Data Bytes for
    Register #2
    Hi
    Lo
    CC
    CC
    /
    /
    /
    /
    /
    /
    2
    2
    2
    2
    2
    2
    Operatio
    n
    -1*2=
    -1*2=
    *2=
    -1*2=
    *2=
    *2=
    -1*2=
    *2=
    -1*2=
    -1*2=
    *2=
    *2=
    -1*2=
    -1*2=
    *2=
    *2=
    -1*2=
    -1*2=
    *2=
    *2=
    -1*2=
    -1*2=
    *2=
    Result
    52.700000
    26.350000
    13.175000
    6.587500
    3.293750
    1.646875
    =
    =
    =
    =
    =
    =
    Result
    Bit
    1.29375
    0.5875
    1.175
    0.35
    0.7
    1.4
    0.8
    1.6
    1.2
    0.4
    0.8
    1.6
    1.2
    0.4
    0.8
    1.6
    1.2
    0.4
    0.8
    1.6
    1.2
    0.4
    0.8
    1
    0
    1
    0
    0
    1
    0
    1
    1
    0
    0
    1
    1
    0
    0
    1
    1
    0
    0
    1
    1
    0
    0
    CRC
    Lo
    4A
    Hi
    18
    The response from this command is similar to the command sent except that the number of
    data bytes and the data bytes themselves are not echoed:
    Device
    Address
    01
    Function
    Code
    10
    Address
    Hi
    Lo
    0C
    C4
    Number of
    Registers
    Hi
    Lo
    00
    02
    CRC
    Lo
    03
    Hi
    65
    NOTE
    Sending 32 bit values are typically not necessary. Sending the data as a 16 bit
    integer only or a 16 bit integer and 16 bit fraction will satisfy most requirements. Some
    systems have 32 bit capability built directly into their products. We have provided this
    feature for those systems.
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    CAUTION
    The position of the REMOTE COMMUNICATIONS DISABLED/ENABLED
    selector switch is NOT considered when forcing coils or writing registers to the CMC.
    Reads and Writes are always enabled. Repeatedly writing a value to a register or
    forcing a coil without regard to the position of the switch can effectively disable a local
    write. Please use caution when writing registers or forcing coils. The REMOTE
    COMMUNICATIONS DISABLED/ENABLED selector switch is typically located on the
    front door of the Compressor’s Control Panel.
    Example: Presetting a 16-bit Integer and 16-bit Fraction Holding Register
    Change the integer and fraction value for the user pressure setpoint (absolute address
    40269, relative address 01-0C) to 110.5 psi. The integer portion of the number 110 (00-6E
    hex) is placed at address 40269 and the fraction 0.5 is converted to 5000 (13-88 hex) and
    is placed at address 40270 (or the second data byte). To change the register, issue the
    following command...
    Device
    Address
    01
    Function
    Code
    10
    Address
    Hi
    Lo
    01
    0C
    Number of
    Registers
    Hi
    Lo
    00
    02
    Number
    of Data
    Bytes
    04
    Data Bytes for
    Register #1
    Hi
    Lo
    00
    6E
    Data Bytes for
    Register #2
    Hi
    Lo
    13
    88
    CRC
    Lo
    92
    Hi
    E1
    The response from this command is similar to the command sent except that the number of
    data bytes and the data bytes themselves are not echoed:
    Device
    Address
    01
    Function
    Code
    10
    Address
    Hi
    Lo
    01
    0C
    Number of
    Registers
    Hi
    Lo
    00
    02
    CRC
    Lo
    80
    Hi
    37
    Exception Responses
    Except for broadcast messages, when a master device sends a query to a slave device it
    expects a normal response, in all other cases a time out or exception response is returned.
    The four possible responses to a the master's query are:
    •
    If the slave device receives the query without a communication error, and can handle
    the query normally, it returns a normal response.
    •
    If the slave does not receive the query due to a communication error, no response is
    returned. The master program will eventually process a time-out condition for the query.
    •
    If the slave receives the query, but detects a communication error (parity, or CRC), no
    response is returned. The master program will eventually process a time-out condition
    for the query.
    •
    If the slave receives the query without a communication error, but cannot handle it (for
    example, if the request is to read a nonexistent coil or register), the slave will return an
    exception response informing the master of the nature of the error.
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    The exception response message has two fields that differentiate it from a normal
    response:
    Function Code Field
    For a normal response, the UCM echoes the function code of the original query in the
    function code field of the response. All function codes have their most significant bits set to
    zero; therefore, the values are always below 80 hexadecimal. When an exception response
    occurs, the UCM sets the most significant bit of the function code to 1. This makes the
    function code value in an exception response exactly 80 hexadecimal higher than the value
    would be for a normal response.
    7
    1
    Most Significant Bit
    6
    5
    4
    0
    0
    0
    3
    0
    Least Significant Bit
    2
    1
    0
    0
    0
    0
    With the function code's most significant bit set, the application program can recognize an
    exception response and can examine the data field for the exception code.
    Data Field
    For a normal response, the UCM will return information in the data field (depending upon
    the query message sent). For an exception response, the UCM returns an exception code
    in the data field. This defines the UCM’s condition that caused the exception.
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    Exception Codes Supported by the CMC Microcontroller
    Code
    01
    Name
    Illegal Function
    Meaning
    The function code received in the query is not an allowable action for the slave. This exception code happens when:
    (1) the function code is other than 1, 2, 3, 4, 5, 6, 15 or 16
    (2) a message has the incorrect number of bytes for the function specified
    02
    Illegal Data Address
    The data address received in the query is not an allowable address for the slave. This exception code happens when:
    (1) the address is not programmed into the Base Control Module (BCM)
    (2) the address is outside of the ranges
    (a) 00001-00512 for coils
    (b) 10001-10512 for discrete inputs
    (c) 30001-31024 for integer and fractional analog inputs
    (d) 33001-34024 for floating point analog inputs
    (e) 40001-41024 for integer and fractional input registers
    (f) 43001-44024 for floating point analog input registers
    03
    Illegal Data Value
    A value contained in the query data field is not an allowable value for the slave. This exception code happens when:
    (1) the number of coils, discrete inputs, registers or analog inputs is equal to zero
    (2) request for more than the maximum number of parameters
    (3) the force single coil command, Function 05, is issued and the value is other than FF00 or 0000
    (4) the force multiple coil command, Function 15, is issued and the number of bytes does not equal the number of bits
    to set
    (5) the preset single register command, Function 6, and preset multiple registers commands, Function 16, is issued
    and the starting address is not even, the number of registers specified does not correspond to the number of bytes in
    the message, the integer part of the number is outside the range –32768 to +32767, the fractional part of the number
    is outside of the range 0-9999, or the value is not a valid 32 bit IEEE floating point number
    04
    Slave Device Failure
    An unrecoverable error occurred while the slave was attempting to perform the requested action. This exception code
    happens when:
    (1) no response from the Base Control Module (BCM) since 800 milliseconds from the time the message was sent …
    BCM not wired properly, BCM hardware problem or BCM Module ID not equal to one
    (2) when there is an unexpected response from the BCM … this is the default exception response
    Maximum Query / Response Parameters
    The listing below shows the maximum amount of data that the CMC Microcontroller can
    return in a single slave response from a valid MODBUS command.
    Function
    Dec
    Hex
    01
    01
    02
    02
    03
    03
    04
    04
    05
    05
    06
    06
    15
    0F
    16
    10
    Description
    Read Coil Status
    Read Input Status
    Read Holding Registers
    Read Input Registers
    Force Single Coil
    Preset Single Register
    Force Multiple Coils
    Preset Multiple Registers
    Maximum
    Parameters
    512 coils
    512 inputs
    64 registers
    64 registers
    1 coil
    1 register
    512 coils
    64 registers
    CMC Data
    The CMC Microcontroller supports several data types. They are coil, integer, fraction and
    floating point.
    •
    Coil - 1 bit, 1 means True or Active, 0 means False or Not Active.
    •
    Integer - 16 bit signed integer, –32768 to +32767.
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    •
    Fraction - 16 bit unsigned integer, 0 – 9999, represents the decimal (fractional) part of
    the number (1 represents 0.0001, 10 represents 0.0010, 100 represents 0.0100 and
    1000 represents 0.1000).
    •
    Floating Point - 32 bit IEEE number (requires reading two registers to get full number).
    For example if the System Pressure input is located on Channel 3 (address 30007) and the
    value of the pressure is 100.5 then:
    Address 30007 contains 100
    Address 30008 contains 5000
    Address 33007 contains the high 16 bits of the IEEE value for 100.5
    Address 33008 contains the low 16 bits of IEEE value for 100.5
    Additionally, the type of data in a location determines the commands that can be used to
    access the data. For the previous example of System Pressure addresses 00007, 03007,
    10007, 13007, 40007 and 43023 return errors because coil, input status and holding
    register commands cannot read input register data.
    Scaling and Units of Measure
    The MODBUS data are scaled in English engineering units. All pressures are in psi,
    temperatures in degrees F, vibrations in mils, and current in amps. For example, when the
    CMC Operator User Interface displays the system pressure as 7.73 kg/cm2, the value for
    system pressure obtained through MODBUS communications is 110 psi.
    Communication Parameters
    Configuration of the communication speed (baud rate), parity, number of data bits and
    number of stop bits is available through the Ingersoll-Rand Service Tool and will be
    provided by a certified Ingersoll-Rand Service Representative.
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    115
    The CMC-DF1 Interface
    Introduction
    Customers may want to communicate to the CMC control systems for remote compressor
    control and monitoring through their Allen-Bradley data highway plus (DH+) network.
    Adding Allen-Bradley DF1 protocol to the UCM module allows our customers to incorporate
    our compressors into their plant-wide Allen-Bradley PLC control system. This
    communication capability also provides for flexibility in the customer's compressed air
    operation through remote start, stop, and data gathering for preventative maintenance.
    The customer or his representative must write system software to suit his individual needs
    for remote control and monitoring. Since the customer writes this interface, the system can
    be as flexible as the customer desires.
    One avenue for communicating with the CMC is via DF1 protocol over a full duplex RS-422
    link. This requires an Allen-Bradley interface module 1770-KF2 to link our intelligent RS422A asynchronous device, Universal Communication Module (UCM), to the Allen-Bradley
    DH+ network.
    The CMC Microcontroller can communicate with other devices over a variety of
    communication standards. Supported standards, or protocols, include RS-232, IRBUS
    (Ingersoll-Rand Proprietary), Modicon’s MODBUS, and Allen-Bradley DF1. The built-in
    ports of the CMC’s Universal Communication Module access communications. This UCMDF1 Interface defines the message structure that a CMC Microcontroller uses to exist on a
    DH+ network. This interface will allow the DH+ network to gather information and control
    the compressor.
    The information presented in these sections that follow do not include the Allen-Bradley
    DF1 protocol details. Detailed information can be obtained from “Allen-Bradley Publication
    1770-6.5.117 - October 1996” - DF1 Protocol and Command Set Reference Manual and
    “Data Highway or Data Highway Plus Asynchronous (RS-232-C or RS-422-A) Interface
    Module (Cat. No. 1770-KF2) User’s Manual”.
    A DH+ link implements peer-to-peer communication with a token-passing scheme to rotate
    mastership among the nodes connected to that link. In order to communicate over AllenBradley DH+ network, an Allen-Bradley 1770-KF2 interface module must be used. The
    1770-KF2 always acts as one node on the DH+ network, which translates DH+ messages
    to DF1 format, and passes these messages on to the UCM on the RS-422A asynchronous
    end, or vice versa.
    The following is a picture of 1770-KF2:
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    Full-Duplex Protocol
    The UCM-DF1 interface only supports the point-to-point full-duplex DF1 protocol, which is
    like a two-lane bridge; traffic can travel in both directions at one time. Full-duplex protocol
    also provides higher performance applications to get the highest possible throughput.
    DF1 Full-Duplex Protocol Message Frames
    The following table shows the general format of a DF1 full-duplex message frame. The
    control symbols DLE STX bytes are sender symbols indicating the start of a message
    frame. The control symbols DLE ETX BCC (CRC) bytes are sender symbols that terminates
    a message frame. The bytes comprised in the command data field vary from command to
    command.
    DLE STX DST
    SRC CMD STS TNS
    Command Data
    DLE
    ETX
    BCC(CRC)
    NOTE
    The standard definitions of the control characters used by DF1 full-duplex protocol
    are listed below:
    Abbreviation
    STX
    ETX
    ENQ
    ACK
    DLE
    NAK
    Hexadecimal Value
    02
    03
    05
    06
    10
    0F
    DF1 Device Address
    Configuration of the DF1 device address is available through the Ingersoll-Rand UCMWizard Tool and will be configured by a certified Ingersoll-Rand Service Representative.
    CAUTION
    The UCM must be configured to have the same node address as 1770-KF2
    interface module. Otherwise, the DF1 messages will not be relayed to the IRBUS port
    of the UCM.
    Destination (DST) Byte
    This byte indicates the destination node address for the message. For a command
    message, it will be the address of the 1770-KF2 module. The UCM must have the same
    address as the 1770-KF2, which can be configured using the Ingersoll-Rand UCM-wizard
    software.
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    Source (SRC) Byte
    This byte indicates the source node address of the message. If the command is initiated
    from an Allen-Bradley PLC, the SRC byte will be the address of the processor module.
    Command (CMD) and Function (FNC) Bytes
    The CMD byte defines the command type. The FNC byte defines the specific function
    under that command type. These bytes together define the activity being performed by the
    command message at the destination node. The message format depends on the CMD and
    FNC values.
    CMD Byte
    Bit:
    7
    0
    6
    0:Command msg
    1:Reply msg
    5
    0: normal priority(for DH+)
    1: high priority(only applies to DH link)
    4
    0
    3 2 1 0
    Command code
    From the figure above, the CMD byte of a reply message for DH+ network is always 40h
    ORed with the CMD byte of its original command message.
    Status (STS) Byte - Status Error Code
    Bit:
    7
    6
    5
    4
    Remote Error Nibble
    3
    2
    1
    0
    Local Error Nibble
    Bits 7, 6, 5, and 4 are used to report remote errors - errors that occur when the command
    executor at the destination node tries to execute the command message. Bits 3, 2, 1, and 0
    are used to report local errors - errors found by the local source node and code 09h through
    0Fh are not used. The UCM-DF1 driver uses mainly the higher nibble to report errors occur
    in CMC. A special error code with non-zero local error nibble, 3Fh, is used to report errors
    caused by illegal CMC data table address or count. The maximum number of data table
    entries allowed to be read or set for CMC is 16 currently. If a read command requests more
    than 16 data items from CMC, an exception response of 3Fh will be returned.
    Following is a list of status error code supported by the UCM-DF1 driver:
    Transaction (TNS) Bytes
    The two TNS bytes contain a unique 16-bit transaction identifier. Generate this number by
    maintaining a 16-bit counter. Increment the counter each time your command initiator
    creates a new message, and store the counter value in the two TNS bytes of the new
    message. You must use only one TNS counter in a multi-tasking environment.
    If the command initiator is an Allen-Bradley PLC, the PLC will maintain the counter
    internally. The reply message should have the same TNS value as the original command
    message. The UCM-DF1 driver copies the original TNS field of the command message into
    the TNS field of the corresponding reply message.
    BCC (Block Check Character) and CRC (Cyclic Redundancy Check)
    At the end of each DF1 command message, there is a one-byte BCC field, or a two-byte
    CRC field for error checking. These bytes allow you to verify the accuracy of each message
    frame transmission. SW-1 of 1770-KF2 module allows you to select BCC or CRC error
    checking for the command messages sent to CMC. The Ingersoll-Rand UCM-wizard
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    software allows you to configure BCC or CRC error checking for the UCM-DF1 driver,
    which needs to be the same error checking method as 1770-KF2.
    BCC (One Byte)
    The BCC field contains the 2’s compliment of the 8-bit sum of all data bytes between DLE
    STX and DLE ETX BCC control characters. BCC provides a medium level of data security.
    It cannot detect either the transposition of bytes during transmission nor the insertion or
    deletion of the value zero within a message frame.
    Another way to quickly determine a BCC value, add up the hex values of all data bytes
    between DLE STX and DLE ETX BCC in the message frame. If the total is greater than
    100h, drop the most significant digit, and then subtract the result from 100h. This gives you
    the BCC.
    CRC (Two Bytes)
    This provides a higher level of data security than BCC but is more difficult to implement. All
    the data bytes between DLE STX and DLE ETX CRC plus the ETX byte are used to
    calculate the CRC value.
    The following explains how to calculate the CRC value:
    •
    Before starting the calculation, a 16-bit register used to store the CRC value is cleared
    to be zero.
    •
    As a byte is fetched from the data buffer, it is XORed (least-significant bit to the right)
    with the right eight bits of the CRC register.
    •
    The result is placed in the right eight bits of the CRC register.
    •
    Inserting 0s on the left then shifts the 16-bit CRC Register right eight times. Each time a
    1 is shifted out on the right, the CRC register is XORed with a 16-bit constant A0-01h.
    •
    As each additional byte is fetched, it is included in the value in the register the same
    way.
    •
    After the ETX byte transmitted is also included in the calculation, the CRC calculation is
    complete. The 16-bit CRC value is transmitted low byte first then high byte.
    Comparing the calculated BCC/CRC bytes with the received BCC/CRC bytes always
    validates the DF1 messages received by UCM.
    CAUTION
    To transmit the data value of 10 hex, you must use the data symbol DLE DLE
    (double-stuffing DLEs). However, only one of these DLE bytes is included in the
    BCC/CRC calculation. However, if your BCC check sum is 10 hex, send it as DLE
    and not DLE DLE.
    The rest of this section explains the meaning of the data bytes between DLE STX and DLE
    ETX BCC/CRC control characters.
    Usually, a command message stripping off the control characters has the following format,
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    DST
    SRC
    CMD
    STS
    TNS
    command specific data packet
    a reply message to a read command has the format below,
    SRC
    DST
    CMD
    STS
    TNS
    command specific data packet
    a reply message to a write command has the following format,
    SRC
    DST
    CMD
    STS
    TNS
    The DST and SRC bytes of a reply message are formed by interchanging the DST and
    SRC bytes of the corresponding command message. The combination of SRC, CMD, and
    TNS bytes uniquely identifies every message packet. If all fields are the same, the message
    is considered to be a duplicate. The UCM-DF1 driver does not detect duplicate messages.
    Scaling and Units of Measure
    The MODBUS data are scaled in English engineering units. All pressures are in psi,
    temperatures in degrees F, vibrations in mils, and current in amps. For example, when the
    CMC Operator User Interface displays the system pressure as 7.73 kg/cm2, the value for
    system pressure obtained through MODBUS communications is 110 psi.
    Data Addressing
    The CMC is primarily a 32-bit floating-point microprocessor controller. We support two
    methods for determining the analog data value. These methods are two 16-bit integers
    representing the integer and fraction part of the number and one 32-bit IEEE floating point
    number. (NOTE: If you use the 16-bit system, you must get two 16-bit numbers and
    combine them into one 32-bit floating point number.) The UCM-DF1 interface can prepare
    data as either two 16-bit integers or one 32-bit floating point number with respect to the
    received DF1 command. The Allen-Bradley PLC floating point format is a subset of IEEE
    STD 754-1985.
    Accessing data from the CMC via DF1 interface emulates accessing data from a PLC5 or
    SLC5/04. In SLC 5/04, each data file can hold up to 256 data elements (element number: 0255) and the file number has to be in the same range (0-255). The UCM-DF1 addressing
    scheme uses this file/element structure and complies with the SLC5/04’s limits on file
    number and element number. Please see next section for details.
    A DF1 command initiator is a device on the DH+ network that initiates the query or set
    commands to the CMC. It can be an Allen-Bradley PLC or other device that can
    send/receive a PLC5 Typed Read (Write) or SLC Typed Logical Read (Write)
    command/response.
    CMC as PLC5
    As to treating CMC as a PLC5, the command initiator can issue a PLC5 Typed Read
    (Write) command to the CMC. Please see the section on Supported Functions for detailed
    message format.
    For a PLC5 Typed Write command, the data can be sent as either two 16-bit integers or
    one 32-bit floating point. If a PLC5 or SLC5/04 issues the command, the setpoint data type
    is determined by the local data file type used to store it.
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    The PLC5 Typed Read commands for requesting data in integer or float format is exactly
    the same messages. The UCM-DF1 driver cannot tell the requested data type from the
    command bytes received. Therefore, the returned data type has to be pre-configured in
    UCM via the Ingersoll-Rand UCM-wizard tool. Default is the integer type. If a PLC5 or
    SLC5/04 issues the command, the local data file used to store the gathered data should be
    the same type. Otherwise, you get erroneous data or an error status code due to data type
    mismatch.
    CMC as SLC5/04
    As to treating a CMC as a SLC5/04, the command initiator can issue a SLC Typed Logical
    Read (Write) command to the CMC. Please see the section on Supported Functions for
    detailed message format.
    If the command initiator is another SLC5/04, you can do either integer or float data type.
    However, if the command initiator is a PLC5, only integer type is supported for the time
    being.
    Data File Addressing for PLC5/SLC504
    When RSLogix software is used to program message instructions in PLC for sending
    read/write commands to the CMC, the target data table address is in the form of either
    Fxx:yyy or Nxx:yyy, where xx is the file number (10-14) and yyy (0-255) is the
    corresponding CMC data table address. The target file type (F for float, N for integer)
    should be consistent with the local file type.
    NOTE
    File numbers 10-14 are reserved for address only!
    The UCM-DF1 interface designates file number 10 for discrete usage (READ ONLY). Each
    element represents 16 Boolean data bit-packed together in two bytes. File type can be
    either N (integer) or B (bit) type. The following table shows the address in file 10 for discrete
    values.
    PLC
    File
    Address
    B10:10
    B10:11
    B10:12
    B10:13
    CMC Data Table
    Address
    (decimal)
    160-175
    176-191
    192-207
    208-223
    15
    175
    191
    207
    223
    14
    174
    190
    206
    222
    13
    173
    189
    205
    221
    12
    172
    188
    204
    220
    11
    171
    187
    203
    219
    16 Discretes
    Packed as Binary Bits in Two Bytes
    10
    9
    8
    7
    6
    5
    170
    169
    168
    167
    166
    165
    186
    185
    184
    183
    182
    181
    202
    201
    200
    199
    198
    197
    218
    217
    216
    215
    214
    213
    4
    164
    180
    196
    212
    3
    163
    179
    195
    211
    2
    162
    178
    194
    210
    1
    161
    177
    193
    209
    0
    160
    176
    192
    208
    Bit 10-15 of integer element 10 in data file 10 represents digital input channels 1-6 (CMC
    data table address 170-175). Bit 0-9 of integer element 11 represent digital input channels
    7-16 (CMC data table address 176-185). Bit 10-15 of integer element 11 represents digital
    output channels 1-6 (CMC data table address 186-191). Bit 0-9 of integer element 12
    represent digital output channels 7-16 (CMC data table address 192-201). Bit 10-15 of
    integer element 11 represents digital output channels 1-6 (CMC data table address 186191). Bit 10-15 of integer element 12 and bit 0-10 of integer element 13 represent various
    compressor states (CMC data table address 202-218).
    Currently, CMC data table has 512 entries. In order to satisfy the (0-255) limit of elements
    per data file for SLC5/04, the CMC data table is divided into two segments; each has 256
    22204796 Rev. B, Version 3.10
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    CMC TECHNICAL REFERENCE MANUAL
    121
    entries. File number 11 is designated to the first 256 entries. File number 12 is for the
    second 256 entries. If the CMC data table gets expanded later, the subsequent file number
    will be used.
    According to the above, N11:170 refers to the 170-th item in the CMC data table, which is
    the digital input channel 1. Similarly, N12:170 will be the 426-th = (170+256) item in the
    CMC data table. If an invalid file or element number is used, you will get a 3Fh-status error
    code. See the status error code section for details.
    The number of bytes per element is 2 for integer type and 4 for float type. The assigned
    message length in elements for local data file should be a multiple of 2 for integer type. If it
    is an odd number, only the 2-byte integer (whole) part will be transmitted for the last data
    item.
    Since the CMC has programmable analog and discrete inputs and outputs, the programmer
    must use the electrical schematic supplied with the machine to determine which function
    name and units of measure are associated with each input and output.
    22204796 Rev. B, Version 3.10
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    CMC TECHNICAL REFERENCE MANUAL
    CMC Data Addressing
    Refer to the table below for data addresses supported by the UCM-DF1 Interface.
    Data
    Address
    (decimal)
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    Data
    Address
    (hex)
    01
    02
    03
    04
    05
    06
    07
    08
    09
    0A
    0B
    0C
    0D
    0E
    0F
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    1A
    1B
    1C
    1D
    1E
    1F
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    Analog Input, Ch 1 (J2-P1,3)
    Analog Input, Ch 2 (J2-P5,7)
    Analog Input, Ch 3 (J1-P1)
    Analog Input, Ch 4 (J1-P4)
    Analog Input, Ch 5 (J1-P5)
    Analog Input, Ch 6 (J1-P8)
    Analog Input, Ch 7 (J1-P9)
    Analog Input, Ch 8 (J1-P12)
    Analog Input, Ch 9 (J1-P13)
    Analog Input, Ch 10 (J1-P16)
    Analog Input, Ch 11 (J1-P17)
    Analog Input, Ch 12 (J1-P20)
    Analog Input, Ch 13 (J1-P21)
    Analog Input, Ch 14 (J1-P24)
    Analog Input, Ch 15 (J1-P25)
    Analog Input, Ch 16 (J1-P28)
    Analog Input, Ch 17 (J1-P29)
    Analog Input, Ch 18 (J1-P32)
    Analog Input, Ch 19 (J1-P33)
    Analog Input, Ch 20 (J1-P36)
    Analog Input, Ch 21 (J1-P37)
    Analog Input, Ch 22 (J1-P40)
    Analog Input, Ch 23 (J1-P41)
    CT Input (J9-P1,2)
    Reserved
    Analog Output, Ch 1 (J3-P1,3)
    Analog Output, Ch 2 (J3-P4,6)
    Analog Output, Ch 3 (J3-P7,9)
    Analog Output, Ch 4 (J3-P10,12)
    Analog Input, Ch 1 (J2-P1,3) – Hi Trip Setpoint
    Analog Input, Ch 1 (J2-P1,3) – Hi Alarm Setpoint
    Data
    Address
    (decimal)
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    62
    63
    64
    65
    66
    67
    68
    69
    70
    71
    72
    Data
    Address
    (hex)
    2A
    2B
    2C
    2D
    2E
    2F
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    3A
    3B
    3C
    3D
    3E
    3F
    40
    41
    42
    43
    44
    45
    46
    47
    48
    Analog Input, Ch 4 (J1-P4) – Hi Trip Setpoint
    Analog Input, Ch 4 (J1-P4) – Hi Alarm Setpoint
    Analog Input, Ch 4 (J1-P4) - Lo Alarm Setpoint
    Analog Input, Ch 4 (J1-P4) - Lo Trip Setpoint
    Analog Input, Ch 5 (J1-P5) - Hi Trip Setpoint
    Analog Input, Ch 5 (J1-P5) - Hi Alarm Setpoint
    Analog Input, Ch 5 (J1-P5) - Lo Alarm Setpoint
    Analog Input, Ch 5 (J1-P5) - Lo Trip Setpoint
    Analog Input, Ch 6 (J1-P8) - Hi Trip Setpoint
    Analog Input, Ch 6 (J1-P8) - Hi Alarm Setpoint
    Analog Input, Ch 6 (J1-P8) - Lo Alarm Setpoint
    Analog Input, Ch 6 (J1-P8) - Lo Trip Setpoint
    Analog Input, Ch 7 (J1-P9) - Hi Trip Setpoint
    Analog Input, Ch 7 (J1-P9) - Hi Alarm Setpoint
    Analog Input, Ch 7 (J1-P9) - Lo Alarm Setpoint
    Analog Input, Ch 7 (J1-P9) - Lo Trip Setpoint
    Analog Input, Ch 8 (J1-P12) - Hi Trip Setpoint
    Analog Input, Ch 8 (J1-P12) - Hi Alarm Setpoint
    Analog Input, Ch 8 (J1-P12) - Lo Alarm Setpoint
    Analog Input, Ch 8 (J1-P12) - Lo Trip Setpoint
    Analog Input, Ch 9 (J1-P13) - Hi Trip Setpoint
    Analog Input, Ch 9 (J1-P13) - Hi Alarm Setpoint
    Analog Input, Ch 9 (J1-P13) - Lo Alarm Setpoint
    Analog Input, Ch 9 (J1-P13) - Lo Trip Setpoint
    Analog Input, Ch 10 (J1-P16) - Hi Trip Setpoint
    Analog Input, Ch 10 (J1-P16) - Hi Alarm Setpoint
    Analog Input, Ch 10 (J1-P16) - Lo Alarm Setpoint
    Analog Input, Ch 10 (J1-P16) - Lo Trip Setpoint
    Analog Input, Ch 11 (J1-P17) - Hi Trip Setpoint
    Analog Input, Ch 11 (J1-P17) - Hi Alarm Setpoint
    Analog Input, Ch 11 (J1-P17) - Lo Alarm Setpoint
    Analog Input, Ch 1 (J2-P1,3) – Lo Alarm Setpoint
    Analog Input, Ch 1 (J2-P1,3) – Lo Trip Setpoint
    Analog Input, Ch 2 (J2-P5,7) – Hi Trip Setpoint
    Analog Input, Ch 2 (J2-P5,7) – Hi Alarm Setpoint
    Analog Input, Ch 2 (J2-P5,7) – Lo Alarm Setpoint
    Analog Input, Ch 2 (J2-P5,7) – Lo Trip Setpoint
    Analog Input, Ch 3 (J1-P1) – Hi Trip Setpoint
    Analog Input, Ch 3 (J1-P1) – Hi Alarm Setpoint
    Analog Input, Ch 3 (J1-P1) – Lo Alarm Setpoint
    Analog Input, Ch 3 (J1-P1) – Lo Trip Setpoint
    73
    74
    75
    76
    77
    78
    79
    80
    81
    82
    49
    4A
    4B
    4C
    4D
    4E
    4F
    50
    51
    52
    Analog Input, Ch 11 (J1-P17) - Lo Trip Setpoint
    Analog Input, Ch 12 (J1-P20) - Hi Trip Setpoint
    Analog Input, Ch 12 (J1-P20) - Hi Alarm Setpoint
    Analog Input, Ch 12 (J1-P20) - Lo Alarm Setpoint
    Analog Input, Ch 12 (J1-P20) - Lo Trip Setpoint
    Analog Input, Ch 13 (J1-P21) - Hi Trip Setpoint
    Analog Input, Ch 13 (J1-P21) - Hi Alarm Setpoint
    Analog Input, Ch 13 (J1-P21) - Lo Alarm Setpoint
    Analog Input, Ch 13 (J1-P21) - Lo Trip Setpoint
    Analog Input, Ch 14 (J1-P24) - Hi Trip Setpoint
    Description
    Description
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
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    123
    CMC TECHNICAL REFERENCE MANUAL
    Data
    Address
    (decimal)
    83
    84
    85
    86
    87
    88
    89
    90
    91
    92
    93
    94
    95
    96
    97
    98
    99
    100
    101
    102
    103
    104
    105
    106
    107
    108
    109
    110
    111
    112
    113
    114
    115
    116
    117
    118
    119
    120
    121
    122
    123
    124
    125
    126
    127
    128
    129
    130
    131
    132
    133
    134
    135
    136
    137
    138
    139
    140
    141
    Data
    Address
    (hex)
    53
    54
    55
    56
    57
    58
    59
    5A
    5B
    5C
    5D
    5E
    5F
    60
    61
    62
    63
    64
    65
    66
    67
    68
    69
    6A
    6B
    6C
    6D
    6E
    6F
    70
    71
    72
    73
    74
    75
    76
    77
    78
    79
    7A
    7B
    7C
    7D
    7E
    7F
    80
    81
    82
    83
    84
    85
    86
    87
    88
    89
    8A
    8B
    8C
    8D
    Description
    Analog Input, Ch 14 (J1-P24) - Hi Alarm Setpoint
    Analog Input, Ch 14 (J1-P24) - Lo Alarm Setpoint
    Analog Input, Ch 14 (J1-P24) - Lo Trip Setpoint
    Analog Input, Ch 15 (J1-P25) - Hi Trip Setpoint
    Analog Input, Ch 15 (J1-P25) - Hi Alarm Setpoint
    Analog Input, Ch 15 (J1-P25) - Lo Alarm Setpoint
    Analog Input, Ch 15 (J1-P25) - Lo Trip Setpoint
    Analog Input, Ch 16 (J1-P28) - Hi Trip Setpoint
    Analog Input, Ch 16 (J1-P28) - Hi Alarm Setpoint
    Analog Input, Ch 16 (J1-P28) - Lo Alarm Setpoint
    Analog Input, Ch 16 (J1-P28) - Lo Trip Setpoint
    Analog Input, Ch 17 (J1-P29) - Hi Trip Setpoint
    Analog Input, Ch 17 (J1-P29) - Hi Alarm Setpoint
    Analog Input, Ch 17 (J1-P29) - Lo Alarm Setpoint
    Analog Input, Ch 17 (J1-P29) - Lo Trip Setpoint
    Analog Input, Ch 18 (J1-P32) - Hi Trip Setpoint
    Analog Input, Ch 18 (J1-P32) - Hi Alarm Setpoint
    Analog Input, Ch 18 (J1-P32) - Lo Alarm Setpoint
    Analog Input, Ch 18 (J1-P32) - Lo Trip Setpoint
    Analog Input, Ch 19 (J1-P33) - Hi Trip Setpoint
    Analog Input, Ch 19 (J1-P33) - Hi Alarm Setpoint
    Analog Input, Ch 19 (J1-P33) - Lo Alarm Setpoint
    Analog Input, Ch 19 (J1-P33) - Lo Trip Setpoint
    Analog Input, Ch 20 (J1-P36) - Hi Trip Setpoint
    Analog Input, Ch 20 (J1-P36) - Hi Alarm Setpoint
    Analog Input, Ch 20 (J1-P36) - Lo Alarm Setpoint
    Analog Input, Ch 20 (J1-P36) - Lo Trip Setpoint
    Analog Input, Ch 21 (J1-P37) - Hi Trip Setpoint
    Analog Input, Ch 21 (J1-P37) - Hi Alarm Setpoint
    Analog Input, Ch 21 (J1-P37) - Lo Alarm Setpoint
    Analog Input, Ch 21 (J1-P37) - Lo Trip Setpoint
    Analog Input, Ch 22 (J1-P40) - Hi Trip Setpoint
    Analog Input, Ch 22 (J1-P40) - Hi Alarm Setpoint
    Analog Input, Ch 22 (J1-P40) - Lo Alarm Setpoint
    Analog Input, Ch 22 (J1-P40) - Lo Trip Setpoint
    Analog Input, Ch 23 (J1-P41) - Hi Trip Setpoint
    Analog Input, Ch 23 (J1-P41) - Hi Alarm Setpoint
    Analog Input, Ch 23 (J1-P41) - Lo Alarm Setpoint
    Analog Input, Ch 23 (J1-P41) - Lo Trip Setpoint
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Surge Pressure Rate
    Surge Current Rate
    Motor Current
    User Pressure Setpoint
    MinLoad (Throttle Limit, TL)
    MaxLoad (High Load Limit, HLL)
    Autodual Reload Percent
    Autodual Unload Point
    Autodual Unload Timer
    Pressure Setpoint Ramp Rate
    Inlet Valve Unload Position
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Data
    Address
    (decimal)
    142
    143
    144
    145
    146
    147
    148
    149
    150
    151
    152
    153
    154
    155
    156
    157
    158
    159
    160
    161
    162
    163
    164
    165
    166
    167
    168
    169
    170
    171
    172
    173
    174
    175
    176
    177
    178
    179
    180
    181
    182
    183
    184
    185
    186
    187
    188
    189
    190
    191
    192
    193
    194
    195
    196
    197
    198
    199
    200
    Data
    Address
    (hex)
    8E
    8F
    90
    91
    92
    93
    94
    95
    96
    97
    98
    99
    9A
    9B
    9C
    9D
    9E
    9F
    A0
    A1
    A2
    A3
    A4
    A5
    A6
    A7
    A8
    A9
    AA
    AB
    AC
    AD
    AE
    AF
    B0
    B1
    B2
    B3
    B4
    B5
    B6
    B7
    B8
    B9
    BA
    BB
    BC
    BD
    BE
    BF
    C0
    C1
    C2
    C3
    C4
    C5
    C6
    C7
    C8
    Description
    Start Timer
    CT Ratio
    Reserved
    Reserved
    Reserved
    Reserved
    Power on hours
    Running Hours
    Loaded Hours
    Number of starts
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Reserved
    Inlet Valve Proportional Constant
    Inlet Valve Integral Constant
    Reserved
    Bypass Valve Proportional Constant
    Bypass Valve Integral Constant
    Reserved
    Reserved
    Compressor Control Mode
    Digital Input, Ch 1 (J4-P2)
    Digital Input, Ch 2 (J4-P3)
    Digital Input, Ch 3 (J4-P4)
    Digital Input, Ch 4 (J4-P5)
    Digital Input, Ch 5 (J4-P6)
    Digital Input, Ch 6 (J4-P7)
    Digital Input, Ch 7 (J4-P8)
    Digital Input, Ch 8 (J4-P9)
    Digital Input, Ch 9 (J5-P2)
    Digital Input, Ch 10 (J5-P3)
    Digital Input, Ch 11 (J5-P4)
    Digital Input, Ch 12 (J5-P5)
    Digital Input, Ch 13 (J5-P6)
    Digital Input, Ch 14 (J5-P7)
    Digital Input, Ch 15 (J5-P8)
    Digital Input, Ch 16 (J5-P9)
    Digital Output, Ch 1 (J15-P7,8)
    Digital Output, Ch 2 (J15-P5,6)
    Digital Output, Ch 3 (J15-P3,4)
    Digital Output, Ch 4 (J15-P1,2)
    Digital Output, Ch 5 (J14-P7,8)
    Digital Output, Ch 6 (J14-P5,6)
    Digital Output, Ch 7 (J14-P3,4)
    Digital Output, Ch 8 (J14-P1,2)
    Digital Output, Ch 9 (J13-P7,8)
    Digital Output, Ch 10 (J13-P5,6)
    Digital Output, Ch 11 (J13-P3,4)
    Digital Output, Ch 12 (J13-P1,2)
    Digital Output, Ch 13 (J12-P7,8)
    Digital Output, Ch 14 (J12-P5,6)
    Digital Output, Ch 15 (J12-P3,4)
    124
    CMC TECHNICAL REFERENCE MANUAL
    Data
    Address
    (decimal)
    201
    202
    203
    204
    205
    206
    207
    208
    209
    210
    211
    212
    Data
    Address
    (hex)
    C9
    CA
    CB
    CC
    CD
    CE
    CF
    D0
    D1
    D2
    D3
    D4
    Data
    Address
    (decimal)
    213
    214
    215
    216
    217
    218
    220
    221
    222
    223
    224
    225
    Description
    Digital Output, Ch 16 (J12-P1,2)
    Compressor State - Waiting
    Compressor State - Coasting
    Compressor State – Starting
    Compressor State - Not Ready
    Compressor State - Ready
    Compressor State - Surge Unload
    Compressor State - Autodual Unload
    Compressor State - Unloading
    Compressor State - Unloaded
    Compressor State - Min load
    Compressor State - Max load
    Data
    Address
    (hex)
    D5
    D6
    D7
    D8
    D9
    DA
    DC
    DD
    DE
    DF
    E0
    E1
    Description
    Compressor State - Loading
    Compressor State - Loaded
    Compressor State - Full Load
    Compressor State - Analog Input Failed
    Any Compressor Trip
    Any Compressor Alarm
    Remote Acknowledge
    Remote Reset
    Remote Load
    Remote Unload
    Remote Start
    Remote Stop
    Supported Functions
    The listing below shows the DF1 commands supported by the CMC Microcontroller.
    Command
    Code
    (hex)
    0F
    0F
    0F
    0F
    Function
    Code
    (hex)
    68
    67
    A2
    AA
    Function Name
    PLC5 Typed Read
    PLC5 Typed Write
    SLC Typed Logical Read
    SLC Typed Logical Write
    Command 0F/Function 68 - PLC5 Typed Read
    The CMC is treated as a PLC5 when this command is issued. This command reads a block
    of data from CMC starting at a specified data table address.
    As to the format of floating point number, Allen-Bradley DF1 protocol always put low byte
    first then high byte, low word first then high word, which is different from the UCMMODBUS protocol. The byte format for a floating point value, 105.4, is differentiated
    between the two interfaces as below (Byte 1 to 4 is in the order of transmission):
    Protocol
    UCM-MODBUS
    UCM-DF1
    Floating Point Byte Representation
    Byte 1
    Byte 2
    Byte 3
    Byte 4
    42
    D2
    CC
    CD
    CD
    CC
    D2
    42
    Example: Reading an Analog Input
    After reviewing the Electrical Schematic for your compressor, you determine that the analog
    input for system pressure is located on J1-P1 (Channel 3). From the CMC data table above,
    the address is 03h. The UCM should be configured to represent data type as desired.
    Following is a table illustrating how the PLC5 system address is mapped to the CMC data
    table address.
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    CMC TECHNICAL REFERENCE MANUAL
    CMC
    Data
    Address
    3
    254
    255
    256
    259
    PLC5
    Target Data
    Table Address
    N11:3
    N11:254
    N11:255
    N12:0
    N12:3
    07
    07
    07
    07
    07
    00
    00
    00
    00
    00
    PLC5 System Address
    Element
    File
    Number
    0B
    03
    0B
    FE
    0B
    FF
    FF
    0C
    00
    0C
    03
    00
    As 16-Bit Integer and Fraction
    To get the reading of system pressure as 16-bit integer and 16-bit fraction, the following
    command is issued (data are presented in hexadecimal format):
    DLE
    STX
    DST
    SRC
    CMD
    STS
    10
    02
    0D
    11
    0F
    00
    TNS
    21
    FNC
    BD
    68
    Packet
    Offset
    00
    00
    Total
    Trans
    02
    00
    PLC5 System Address
    07
    00
    0B
    03
    Size
    02
    DLE
    ETX
    BCC
    00
    10
    03
    74
    DLE
    10
    ETX
    03
    BCC
    03
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    11
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    21
    BD
    A
    99
    09
    B
    05
    42
    64
    00
    5C
    09
    In the response above, the first two bytes (low byte first then high byte) in field B is the
    integer portion of the system pressure (00-64h, 100 decimal). The second two bytes in field
    B are the fraction portion of the system pressure (09-5Ch, 2396 decimal). Each fraction has
    a range between 0 and 9999. So the system pressure, expressed as a floating-point
    number, is 100.2396 PSIG.
    The following table contains a list of data types and the ID value of each supported by
    Allen-Bradley DF1 protocol:
    Data Type ID
    1
    2
    3
    4
    5
    6
    7
    8
    9
    15
    16
    Data Type
    bit
    bit string
    byte (or character) string
    integer
    Allen-Bradley timer
    Allen-Bradley counter
    Allen-Bradley general control structure
    IEEE floating point
    array of similar elements
    address data
    binary-coded decimal (BCD)
    The first byte, 99h, in field A of the above response message is a flag byte, which has the
    format below:
    Bit:
    7
    1
    Data Type ID
    6
    5
    0
    0
    4
    1
    3
    1
    Data Type Size
    2
    1
    0
    0
    0
    1
    If the data type ID is greater than 7, set bit 7 of this flag byte to 1 and insert the number of
    bytes to follow that contains the data type ID value in bits 4, 5, and 6. These additional ID
    bytes follow directly after the flag byte. In the above response message, the additional one
    byte is 09h, which means array of similar elements.
    22204796 Rev. B, Version 3.10
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    Date of Issue: March 24, 2003
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    If the data type defined uses more than 7 bytes for each data element, enter 1 in bit 3 of the
    flag byte and enter the number of bytes to follow that contains the number of bytes used for
    each data element. These additional size bytes follow the flag byte and any ID bytes.
    The individual bytes in field A and B of the above response message is explained in the
    following table:
    Field
    Byte (hex)
    99
    09
    05
    42
    A
    Definition
    flag byte
    data type ID byte: array of similar elements
    number of bytes to follow
    descriptor byte
    4: type ID for integer
    2: two bytes per element
    64
    00
    5C
    09
    B
    4 data bytes
    As IEEE 32-Bit Floating Point Number
    If the UCM is configured to read data as floating point, the following command is sent:
    DLE
    STX
    DST
    SRC
    CMD
    STS
    10
    02
    0D
    11
    0F
    00
    TNS
    21
    FNC
    BD
    68
    Packet
    Offset
    00
    00
    Total
    Trans
    01
    00
    PLC5 System Address
    07
    00
    0B
    Size
    03
    01
    00
    DLE
    ETX
    10
    03
    BCC
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    11
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    21
    BD
    99
    09
    A
    06
    B
    94
    08
    C6
    D4
    DC
    DLE
    10
    42
    ETX
    03
    BCC
    The individual bytes in field A and B of the above response message is explained in the
    table below:
    Field
    A
    B
    Byte (hex)
    99
    09
    06
    94
    08
    C6
    D4
    DC
    42
    means
    flag byte
    data type ID byte: array of similar elements
    number of bytes to follow
    descriptor byte
    9: one byte to follow
    4: four bytes per element
    type ID for floating point
    4 data bytes
    After the proper byte swapping, the system pressure (42-DC-D4-C6), expressed as a
    floating point number is 110.4155731201 PSIG.
    IEEE floating-point numbers are represented in 32 bits as shown below.
    31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
    exponent
    9
    8
    7
    6
    5
    4
    3
    2
    1
    0
    mantissa
    sign
    Convert hexadecimal words 1 and 2 (W1, W2) into decimal values ...
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    127
    CMC TECHNICAL REFERENCE MANUAL
    Word
    Lo 1
    Lo 1
    Hi 2
    Hi 2
    Byte
    Lo
    Hi
    Lo
    Hi
    Symbol
    W1LB
    W1HB
    W2LB
    W2HB
    Hex
    C6
    D4
    DC
    42
    Decimal
    198
    212
    220
    66
    Determine the sign (positive = 0 or negative = 1) ...
    Sign = (W2HB And 128) / 128, where And is defined as a bit-wise And
    Sign = (66 And 128) / 128 = 0
    Determine the exponent ...
    Exponent = ((W2HB And 127) * 2) + INT (W2LB / 128), where INT is defined as
    INTEGER
    Exponent = ((66 And 127) * 2) + INT (220/128) = 133
    Determine the mantissa...
    Mantissa = ((((W2LB And 127) * 256) + W1HB) * 256) + W1LB
    Mantissa = ((((220 And 127) * 256) + 212) * 256) + 198 = 6083782
    Putting the 32 bit IEEE value together...
    Value = (-1sign) * (2(exponent - 127)) * ((Mantissa * 2-23) + 1)
    Value = (-10) * (2(133- 127)) * ((6083782 * 2-23) + 1) = 110.4155731201
    NOTE
    When Sign = Exponent = Mantissa = 0, Value = 0. This is a special case for the
    above equation.
    Example: Read Multiple Analog Channels
    The procedure for reading multiple channels is the same as reading a single channel with
    the exception of requesting more data. The message length in elements should be set as
    desired but no more than 16 data at a time, because IRBUS can handle at most 16 data in
    one query for the time being.
    NOTE
    A contiguous group of data (channels) must be read for a single command.
    Example: Reading a Discrete Value
    Reading discrete values from file number 11 or higher is the same as reading analog data.
    To read a digital output (Channel 3, 188h) as a two-byte integer, the following command is
    sent:
    DLE
    STX
    DST
    SRC
    CMD
    STS
    10
    02
    0D
    11
    0F
    00
    TNS
    A1
    C2
    FNC
    68
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Packet
    Offset
    00
    00
    Total
    Trans
    01
    00
    PLC5 System
    Address
    07
    00
    0B
    BC
    Size
    01
    00
    DLE
    ETX
    BCC
    10
    03
    38
    128
    CMC TECHNICAL REFERENCE MANUAL
    The response to this command is:
    DLE
    10
    STX
    02
    DST
    11
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    A1
    C2
    A
    99
    09
    B
    03
    42
    01
    DLE
    10
    00
    ETX
    03
    BCC
    48
    Example: Reading Multiple Discrete Values
    To read digital output channels 1-6 as integers, the following command is sent:
    DLE
    STX
    DST
    SRC
    CMD
    STS
    10
    02
    0D
    11
    0F
    00
    TNS
    41
    FNC
    17
    Packet
    Offset
    00
    00
    68
    Total
    Trans
    0C
    00
    PLC5 System
    Address
    07
    00
    0B
    BA
    Size
    0C
    00
    DLE
    ETX
    BCC
    10
    03
    2F
    The response to this command is:
    DLE
    10
    STX
    02
    DST
    11
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    41
    17
    A
    99
    09
    B
    19
    42
    00
    00
    00
    00
    B
    00
    00
    00
    00
    00
    00
    00
    00
    00
    00
    00
    00
    DLE
    10
    00
    00
    00
    ETX
    03
    00
    01
    00
    00
    00
    BCC
    3D
    Example: Reading Bit-Packed Discrete Data
    Reading discrete values from file number 10 is to read the 16 bit-packed discrete values in
    a two-byte integer format. When the following command is sent,
    DLE
    STX
    DST
    SRC
    10
    02
    0D
    11
    CMD
    STS
    0F
    00
    TNS
    61
    C4
    FNC
    68
    Packet
    Offset
    00
    00
    Total
    Trans
    01
    00
    PLC5 System Address
    07
    00
    0A
    Size
    0B
    01
    00
    DLE
    ETX
    BCC
    10
    03
    28
    the response from this command is:
    DLE
    10
    STX
    02
    DST
    11
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    61
    C4
    A
    99
    09
    03
    42
    28
    B
    10
    10
    DLE
    10
    ETX
    03
    BCC
    4F
    NOTE
    The data value 10h in field B is transmitted as 10h 10h to be distinguished from the
    control character DLE. Please see the DF1 Full-Duplex Protocol Message Frames
    section for more details.
    In the above example, the local data file type can be either bit or integer types. Local data
    element B10:11 covers CMC data table address 176-191. Bit 10-15 is for digital output
    channels 1-6. You can determine the remote trouble contact (Channel 3, J15-P3,4) by bit
    12 in the returned integer. The table below graphically depicts the individual bit value for the
    returned two-byte integer.
    Response (hex)
    Byte 1
    Bit
    CMC Data Address
    28
    Bit
    CMC Data Address
    Byte 2
    10
    7
    183
    0
    15
    191
    0
    6
    182
    0
    14
    190
    0
    5
    181
    1
    13
    189
    0
    4
    180
    0
    12
    188
    1
    3
    179
    1
    11
    187
    0
    2
    178
    0
    10
    186
    0
    1
    177
    0
    9
    185
    0
    0
    176
    0
    8
    184
    0
    A bit response of 1 means that the output is ON and a response of 0 means that the output
    is OFF.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    129
    CMC TECHNICAL REFERENCE MANUAL
    Command 0F/Function 67 - PLC5 Typed Write
    CAUTION
    The position of the REMOTE COMMUNICATIONS DISABLED/ENABLED
    selector switch is NOT considered when forcing coils or writing registers to the CMC.
    Reads and Writes are always enabled. Repeatedly writing a value to a register or
    forcing a coil without regard to the position of the switch can effectively disable a local
    write. Please use caution when writing registers or forcing coils. The REMOTE
    COMMUNICATIONS DISABLED/ENABLED selector switch is typically located on the
    front door of the Compressor’s Control Panel.
    The CMC is treated as a PLC5 when this command is issued. This command writes data to
    the CMC starting at the specified data table address. You can write to a setpoint with either
    an integer or floating point number.
    Example: Presetting Analog Setpoints for 32-bit Values
    To write 105.4 PSIG as a floating point number to the user pressure setpoint (CMC data
    table address, 86h), issue the following command:
    DLE
    STX
    DST
    SRC
    CMD
    STS
    10
    02
    0D
    11
    0F
    00
    81
    CE
    67
    A
    06
    94
    08
    CD
    CC
    99
    09
    TNS
    FNC
    Packet
    Offset
    00
    00
    B
    D2
    42
    Total
    Trans
    01
    00
    DLE
    10
    ETX
    03
    PLC5 System
    Address
    07
    00
    0B
    86
    BCC
    93
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    11
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    81
    CE
    DLE
    10
    ETX
    03
    BCC
    44
    The difficulty in setting 32-bit values is determining the four data bytes for the number you
    want to send. The process required is ...
    1. Determine the sign (positive = 0 or negative = 1). This is the first bit.
    2. Divide the decimal value by 2 until the result is less than 2, but greater than 1. Count
    the number of iterations required. Add 127 to the number of iterations. This result is the
    exponent. Convert this result to binary. These are the next eight bits.
    3. From the result obtained from step 2, subtract 1. Then, multiply this result by 2. If the
    result is less than 1, then the value of the first mantissa bit is 0. Otherwise, the mantissa
    bit is 1. If the result is greater than or equal to 1, then subtract 1 from the result and
    proceed with step 3 until the result is 0 or you have gone through this process 23 times.
    4. Combine all 32 bits from the steps above and convert this value to hexadecimal. These
    32 bits are the 4 hexadecimal data bytes needed for the command.
    As an example, we will start with the decimal value of 105.4.
    1. Since this is a positive number, the first bit is 0.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    130
    CMC TECHNICAL REFERENCE MANUAL
    2. Determine the exponent bits by ...
    Iteration
    1
    2
    3
    4
    5
    6
    Decimal
    105.40000
    52.70000
    26.35000
    13.17500
    6.58750
    3.29375
    /
    /
    /
    /
    /
    /
    2
    2
    2
    2
    2
    2
    =
    =
    =
    =
    =
    =
    Result
    52.700000
    26.350000
    13.175000
    6.587500
    3.293750
    1.646875
    It took us six iterations to get the result to a number that is less than two and greater than or
    equal to one. Now, we must add 127 for an exponent of 133. Converting this to binary, the
    next eight bits are represented as 10000101.
    3. Determine the mantissa bits by ...
    Iteration
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    Decimal
    1.646875
    1.29375
    0.5875
    1.175
    0.35
    0.7
    1.4
    0.8
    1.6
    1.2
    0.4
    0.8
    1.6
    1.2
    0.4
    0.8
    1.6
    1.2
    0.4
    0.8
    1.6
    1.2
    0.4
    Operation Result
    - 1 * 2 = 1.29375
    -1*2=
    0.5875
    *2=
    1.175
    -1*2=
    0.35
    *2=
    0.7
    *2=
    1.4
    -1*2=
    0.8
    *2=
    1.6
    -1*2=
    1.2
    -1*2=
    0.4
    *2=
    0.8
    *2=
    1.6
    -1*2=
    1.2
    -1*2=
    0.4
    *2=
    0.8
    *2=
    1.6
    -1*2=
    1.2
    -1*2=
    0.4
    *2=
    0.8
    *2=
    1.6
    -1*2=
    1.2
    -1*2=
    0.4
    *2=
    0.8
    Bit
    1
    0
    1
    0
    0
    1
    0
    1
    1
    0
    0
    1
    1
    0
    0
    1
    1
    0
    0
    1
    1
    0
    0
    From the table above, 10100101100110011001100 represent the next 23 bits.
    4. Combining the bits in sign, exponent and then mantissa order ...
    0100-0010-1101-0010-1100-1100-1100-1100
    This converts to 42-D2-CC-CC in hexadecimal. To conform to DF1 floating point format, the
    bytes are swapped as CC-CC-D2-42.
    Example: Presetting a 16-bit Integer and 16-bit Fraction Analog Setpoint
    To change the integer and fraction value for the user pressure setpoint to 105.4 PSIG,
    issue the command below. The integer portion of the number 105 (00-69h) and the fraction
    0.4 is converted to 4000 (0F-A0h). These four bytes are placed in field B in the order of (6900-A0-0F).
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    131
    CMC TECHNICAL REFERENCE MANUAL
    DLE
    STX
    DST
    SRC
    CMD
    STS
    10
    02
    0D
    11
    0F
    00
    TNS
    41
    FNC
    D0
    67
    A
    99
    09
    Packet
    Offset
    00
    00
    B
    05
    42
    69
    00
    A0
    0F
    Total
    Trans
    02
    00
    DLE
    10
    ETX
    03
    PLC5 System Address
    07
    00
    0B
    86
    BCC
    C0
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    11
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    41
    D0
    DLE
    10
    ETX
    03
    BCC
    82
    Example: Forcing a Coil
    Forcing a single coil to either ON or OFF. Refer to the table below for each coil supported
    by the UCM-DF1 interface. An integer value of one or greater forces the coil to be ON. An
    integer value of zero forces the coil to be OFF.
    CMC Data Table
    Address (decimal)
    220
    221
    222
    223
    224
    225
    CMC Data Table
    Address (hex)
    DC
    DD
    DE
    DF
    E0
    E1
    Coil Name
    (Write only)
    Remote Acknowledge
    Remote Reset
    Remote Load
    Remote Unload
    Remote Start
    Remote Stop
    NOTE
    For the CMC, forcing the above listed coils OFF is not meaningful because the
    default state of each of the above coils is OFF. When using these commands, they
    should be sent once (momentary) and the CMC will execute the commands.
    NOTE
    The Forcing Coil command will override the CMC’s current state. The forced state will
    remain valid until the CMC next solves the coil. The coil will remain forced if it is not
    programmed in the controller's logic.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    132
    CMC TECHNICAL REFERENCE MANUAL
    CAUTION
    For all of the Remote Coils, the compressor’s REMOTE COMMUNICATIONS
    DISABLED/ENABLED selector switch must be in the ENABLED position for these
    commands to execute. When DISABLED, the CMC ignores these coils being forced
    ON. The REMOTE COMMUNICATIONS DISABLED/ENABLED selector switch is
    typically located on the front door of the Compressor’s Control Panel.
    To remotely acknowledge the compressor’s alarm or trip condition, the following command
    is issued:
    DLE
    STX
    DST
    SRC
    CMD
    STS
    10
    02
    0D
    11
    0F
    00
    TNS
    E1
    FNC
    F8
    67
    A
    99
    09
    Packet
    Offset
    00
    00
    B
    03
    42
    01
    Total
    Trans
    01
    00
    DLE
    10
    ETX
    03
    BCC
    BC
    TNS
    E1
    F8
    DLE
    10
    ETX
    03
    00
    PLC5 System Address
    07
    00
    0B
    DC
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    11
    SRC
    0D
    CMD
    4F
    STS
    00
    BCC
    BA
    The following command works the same:
    DLE
    STX
    DST
    SRC
    CMD
    STS
    10
    02
    0D
    11
    0F
    00
    TNS
    41
    FNC
    E3
    67
    A
    99
    09
    Packet
    Offset
    00
    00
    B
    05
    42
    01
    00
    00
    00
    Total
    Trans
    02
    00
    DLE
    10
    ETX
    03
    PLC5 System Address
    07
    00
    0B
    DC
    BCC
    6E
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    11
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    41
    E3
    DLE
    10
    ETX
    03
    BCC
    6F
    Example: Forcing Multiple Coils
    Forces each coil in a series of contiguous coils to either ON or OFF. Refer to the data table
    above for a coil list supported by the UCM-DF1 Interface.
    NOTE
    The Forcing Multiple Coils command will override the CMC’s current state. The forced
    state will remain valid until the CMC next solves the coil. The coil will remain forced if
    it is not programmed in the controller's logic.
    To force a reset (CMC data table address, DDh) and start (CMC data table address, E0h)
    of the compressor the following command is sent:
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    133
    CMC TECHNICAL REFERENCE MANUAL
    DLE
    STX
    DST
    SRC
    CMD
    STS
    10
    02
    0D
    11
    0F
    00
    TNS
    21
    FNC
    0C
    Packet
    Offset
    00
    00
    67
    A
    99
    09
    11
    42
    01
    00
    00
    00
    01
    00
    00
    Total
    Trans
    08
    00
    B
    01
    00
    PLC5 System Address
    07
    00
    00
    00
    00
    DLE
    10
    ETX
    03
    BCC
    66
    0B
    01
    DD
    00
    00
    00
    DLE ETX
    10
    03
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    11
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    21
    0C
    The number of contiguous coils is four (DD, DE, DF, and E0h). The message length of
    integer elements is 8 and the number of data bytes in field B is 16.
    Command 0F/Function A2 - SLC Typed Logical Read
    The CMC is treated as an SLC5/04 when this command is issued. This function reads a
    block of data from CMC starting at a specified data table address.
    Example: Reading an Analog Value
    To read the pressure setpoint (CMC data table address 86h) as a floating point number, the
    following command is issued:
    DLE
    STX
    DST
    10
    02
    0D
    SRC CMD STS
    0B
    0F
    00
    TNS
    D4
    19
    FNC Byte
    Size
    A2
    04
    File
    No.
    0B
    File
    Type
    8A
    Ele
    No.
    86
    S/Ele
    No.
    00
    DLE ETX
    10
    03
    BCC
    2B
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    0B
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    D4
    19
    CD
    CC
    Data
    D2
    42
    DLE
    10
    ETX
    03
    BCC
    FF
    The important command bytes are explained below:
    Field
    Byte Size
    File Number
    Description
    The number of data bytes to be read.
    Address files 0-255 only. For CMC, file 10 is designated for discrete
    only. File (11+N) is for the (N+1) th 256 entries in the CMC data table.
    85h: bit
    89h: integer
    8Ah: float
    Address elements 0-255 only. The address byte format is the same as
    PLC5 for CMC.
    254: (FE)
    255: (FF-FF-00)
    Not used, always 00h.
    File Type
    Element Number
    Sub-Element Number
    The four bytes in data field of the response message are converted to a floating point
    number, 105.4 PSIG.
    To read the pressure setpoint value as integer, the following command is sent:
    DLE
    STX
    DST
    10
    02
    0D
    SRC CMD STS
    0B
    0F
    00
    TNS
    D4
    The response from this command is:
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    27
    FNC Byte
    Size
    A2
    04
    File
    No.
    0B
    File
    Type
    89
    Ele
    No.
    86
    S/Ele
    No.
    00
    DLE ETX
    10
    03
    BCC
    1E
    BCC
    4F
    134
    CMC TECHNICAL REFERENCE MANUAL
    DLE
    10
    STX
    02
    DST
    0B
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    D4
    27
    69
    00
    Data
    A0
    DLE
    10
    0F
    ETX
    03
    BCC
    86
    The first two bytes in data field represent the integer portion, 106 (00-69h), of the setpoint.
    The second two bytes represent the fraction portion, 4000 (0F-A0h), of the setpoint.
    Example: Reading Multiple Analog Values
    The following command reads analog inputs channels 3-9 as integer:
    DLE
    STX
    DST
    10
    02
    0D
    SRC CMD STS
    0B
    00
    0F
    TNS
    D5
    A9
    FNC Byte
    Size
    1C
    A2
    File File
    No. Type
    0B
    89
    Ele
    No.
    03
    21
    00
    0A
    S/Ele
    No.
    00
    DLE ETX
    10
    03
    BCC
    06
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    0B
    SRC
    0D
    CMD
    4F
    STS
    00
    00
    00
    TNS
    D5
    A9
    FF
    63
    0B
    00
    5C
    Data
    00
    66
    2E
    14
    09
    BC
    00
    0F
    83
    Data
    20
    00
    DLE
    10
    1E
    D6
    ETX
    03
    00
    62
    00
    E7
    0B
    BCC
    C0
    Example: Reading Single Discrete Data
    After reviewing the Electrical Schematic for your compressor, you determine that the digital
    input for emergency stop push button is located on J4-P5 (Channel 4). The CMC data table
    address is ADh for the input in question. Therefore, to read the state of the emergency stop
    push button as a two byte integer, the following command is issued:
    DLE
    STX
    DST
    10
    02
    0D
    SRC CMD STS
    0B
    0F
    00
    TNS
    D6
    79
    FNC Byte
    Size
    02
    A2
    File File
    No. Type
    0B
    89
    TNS
    D6
    79
    Data
    01
    00
    Ele
    No.
    AD
    S/Ele
    No.
    00
    DLE ETX
    10
    03
    BCC
    A5
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    0B
    SRC
    0D
    CMD
    4F
    STS
    00
    DLE
    10
    ETX
    03
    BCC
    49
    The data response (01) means that the input is ON, or the emergency stop push button is
    pressed.
    Example: Reading 16 Bit-Packed Discrete Data
    To read 16 bit-packed discrete values for digital outputs as a two-byte integer, the following
    command is sent:
    DLE
    STX
    DST
    10
    02
    0D
    SRC CMD STS
    0B
    0F
    00
    TNS
    E1
    41
    FNC Byte
    Size
    02
    A2
    File File
    No. Type
    0A
    85
    Ele
    No.
    0B
    S/Ele
    No.
    00
    DLE ETX
    10
    03
    BCC
    79
    Note that the file number must be 10. The local data file used to store the returned data can
    be either bit (85h) or integer (89h) type. The response from this command is:
    DLE
    10
    STX
    02
    DST
    0B
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    E1
    41
    28
    Data
    10
    10
    DLE
    10
    ETX
    03
    BCC
    3F
    Please refer to the PLC5 Typed Read command section for the method to interpret the 16bit discrete values.
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    CMC TECHNICAL REFERENCE MANUAL
    Command 0F/Function AA - SLC Typed Logical Write
    The CMC is treated as a SLC5/04 when this command is issued. This command writes a
    block of data to CMC starting at a specified data table address. You can write to a setpoint
    with either an integer or floating point number.
    Example: Presetting Analog Setpoint for 32-bit Value
    To write 105.4 PSIG as a floating point number to the user pressure setpoint (CMC data
    table address, 86h), issue the following command:
    DLE
    STX
    DST
    10
    02
    0D
    SRC CMD STS
    0B
    0F
    TNS
    00
    E1
    FNC Byte
    Size
    04
    AA
    70
    File File
    No. Type
    0B
    8A
    Ele
    No.
    86
    S/Ele
    No.
    00
    Data
    CD
    CC
    D2
    DLE
    42
    10
    ETX BCC
    03
    12
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    0B
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    E1
    70
    DLE
    10
    ETX
    03
    BCC
    48
    Example: Presetting a 16-bit Integer and 16-bit Fraction Analog Setpoint
    To change the integer and fraction value for the user pressure setpoint to 105.4 PSIG,
    issue the command below. The integer portion of the number 105 (00-69h) and the fraction
    0.4 is converted to 4000 (0F-A0h). These four bytes are placed in field B in the order of (6900-A0-0Fh).
    DLE
    STX
    DST
    10
    02
    0D
    SRC CMD STS
    0B
    0F
    TNS
    00
    E1
    FNC Byte
    Size
    04
    AA
    82
    File File
    No. Type
    0B
    89
    Ele
    No.
    86
    S/Ele
    No.
    00
    Data
    69
    00
    A0
    DLE
    0F
    10
    ETX BCC
    03
    96
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    0B
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    E1
    82
    DLE
    10
    ETX
    03
    BCC
    36
    Example: Forcing a Coil
    Forces a single coil to either ON or OFF. Refer to the CMC data table for each coil
    supported by the UCM-DF1 interface. See the same example in the PLC5 Typed Write
    command section for more details.
    To remotely acknowledge the compressor’s alarm or trip condition, the following command
    is issued:
    DLE
    STX
    DST
    10
    02
    0D
    SRC CMD STS
    0B
    0F
    00
    TNS
    E1
    FNC Byte
    Size
    AA
    04
    A3
    File
    No.
    0B
    File
    Type
    89
    Ele
    No.
    DC
    S/Ele
    No.
    00
    Data
    01
    00
    00
    DLE
    00
    10
    ETX BCC
    03
    36
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    0B
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    E1
    A3
    DLE
    10
    ETX
    03
    BCC
    15
    To remotely acknowledge the compressor’s alarm or trip condition, the following command
    works the same:
    DLE
    STX
    DST
    10
    02
    0D
    SRC CMD STS
    0B
    0F
    00
    TNS
    E1
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    AD
    FNC Byte
    Size
    AA
    02
    File
    No.
    0B
    File
    Type
    89
    Ele
    No.
    DC
    S/Ele
    No.
    00
    Data
    01
    00
    DLE
    10
    ETX BCC
    03
    2E
    136
    CMC TECHNICAL REFERENCE MANUAL
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    0B
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    E1
    AD
    DLE
    10
    ETX
    03
    BCC
    0B
    Example: Forcing Multiple Coils
    Forces each coil in a series of contiguous coils to either ON or OFF. Refer to the CMC data
    table for a list of coils supported by the UCM-DF1 interface. To force a reset (CMC data
    table address, DDh) and start (E0h) of the compressor, the following command is sent:
    DLE
    STX
    DST
    10
    02
    0D
    SRC CMD STS
    0B
    0F
    00
    TNS
    E2
    FNC
    3A
    AA
    Byte
    Size
    10 10
    File
    No.
    0B
    File
    Type
    89
    Ele
    No.
    DD
    Data
    01
    00
    00
    00
    01
    00
    00
    00
    S/Ele
    No.
    00
    DLE
    10
    ETX
    03
    Data
    01
    00
    00
    00
    01
    00
    00
    00
    BCC
    8E
    NOTE
    The byte size value 10h is transmitted as 10h 10h to be distinguished from the control
    character DLE.
    The response from this command is:
    DLE
    10
    STX
    02
    DST
    0B
    SRC
    0D
    CMD
    4F
    STS
    00
    TNS
    E2
    3A
    DLE
    10
    ETX
    03
    BCC
    7D
    The number of contiguous coils is four (DD, DE, DF, and E0h). The assigned local
    message buffer length is 8 integer elements, which is 16-byte long.
    Allen-Bradley SLC 504 Example
    Data Files
    RSLogix 500 Ladder Diagram
    The following ladder logic example is the fastest and most reliable method for gathering
    data from a CMC.
    22204796 Rev. B, Version 3.10
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    137
    CMC TECHNICAL REFERENCE MANUAL
    First Pass
    S2:1
    N7:0
    U
    15
    0000
    15
    MSG
    Read/Write Message
    Peer-To-Peer
    Type
    Read
    Read/Write
    500CPU
    Target Device
    Local
    Local/Remote
    N7:0
    Control Block
    14
    Control Block Length
    Setup Screen
    0001
    N7:0
    N7:0
    12
    10
    EN
    DN
    ER
    N7:0
    U
    15
    0002
    MSG
    Read/Write Message
    Peer-To-Peer
    Type
    Read
    Read/Write
    500CPU
    Target Device
    Local
    Local/Remote
    N7:20
    Control Block
    14
    Control Block Length
    Setup Screen
    N7:0
    0003
    13
    N7:20
    N7:20
    12
    10
    N7:20
    N7:0
    N7:20
    13
    13
    10
    EN
    DN
    ER
    N7:20
    U
    15
    0004
    N7:0
    U
    15
    0005
    0006
    END
    UCM STS Error Codes
    STS Code
    (hex)
    00
    10
    30
    3F
    D0
    E0
    Definition
    Success - no error
    Illegal command or function
    Remote node host is missing, disconnected, or shutdown
    Illegal CMC data address or count
    Illegal data type
    Cannot form CMC data table query/set list
    NOTE
    The UCM-DF1 driver does not support EXT STS. According to Allen-Bradley DF1
    protocol convention, EXT STS is part of the message only if STS = F0h.
    22204796 Rev. B, Version 3.10
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    CMC TECHNICAL REFERENCE MANUAL
    When the CMC receives a DF1 command without any communication error and the
    command is executed successfully, a normal response with status code 00h is returned.
    If the UCM does not receive the command due to a communication error, no response is
    returned and the command initiator will eventually time out.
    If the UCM does receive the command, but detects error (invalid BCC/CRC...), control
    characters DLE NAK is returned to the command initiator, which in turns retransmits the
    command message and restarts a time out to wait for the response. This can be repeated a
    few times depending on the limit preset for retransmission. Once the limit is exceeded, the
    command initiator is informed of the failure and proceeds to the next command.
    If the time out expired before a response is received, the command initiator sends out DLE
    ENQ control characters to request a retransmission of the last response. It restarts a time
    out and wait for the response. There is a limit on the number of inquiries allowed per
    command message. When this limit is exceeded, the command initiator proceeds to the
    next command.
    When UCM receives DLE ENQ or DLE NAK message, it resends the last response to the
    command initiator. When DLE ACK message is received by the UCM, no response is
    returned.
    When the UCM receives a command without any communication error, but cannot handle
    it, the UCM will return an exception response with the appropriate status code informing the
    command initiator of the nature of failure.
    NOTE
    The table below explains the meanings of different control symbols for DF1 protocol:
    Control Symbol
    DLE ACK
    DLE NAK
    DLE ENQ
    Definition
    a message frame has been successfully received
    a message frame was not received successfully
    request retransmission of a response from the destination node
    Communication Parameters
    Configuration of the UCM RS-422 port’s communication speed (baud rate), parity, number
    of data bits, number of stop bits... is available through the Ingersoll-Rand Service Tool for
    the UCM and will be configured by a certified Ingersoll-Rand Service Representative. The
    settings should be the same as the 1770-KF2 interface module.
    Network Setup
    The network diagram that follows depicts the communication interface between AllenBradley DF1 network and Ingersoll-Rand CMC Microcontroller.
    The 1770-KF2 always acts as a slave. The slave cannot initiate a command; i.e., the UCM
    cannot initiate a command over DH+ network. It only returns response messages to queries
    that are addressed to them individually. Broadcast is not supported over the DF1 network.
    22204796 Rev. B, Version 3.10
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    139
    CMC TECHNICAL REFERENCE MANUAL
    CMC Panel
    CENTAC  Microcontroller
    RS-232 Network for
    Operator User Interface,
    Twisted Pair Wires with
    Common (3 Wires)
    IRBUS (RS-485) Network
    for Base Control Modules
    and Universal
    Communication Modules,
    Twisted Pair Wires with
    Ground (3 Wires)
    Base
    Control
    Module
    (BCM)
    IRBUS
    Address: 1
    Serial Port
    (COM1)
    INGERSOLL-RAND
    Service Tool
    470
    ohm
    IRBUS IN
    (For IR Use)
    IRBUS OUT
    (For IR Use)
    Base
    Control
    Module
    (BCM)
    Service Tool
    Plug on
    Panel Door
    Universal
    Communication
    Module (UCM)
    IRBUS
    Address 4
    Network Card
    Comm Port on
    Server
    IRBUS
    Address: 2
    INGERSOLL-RAND
    Air System Controller
    (ASC)
    Universal
    Comm.
    Module
    (UCM)
    IRBUS
    Address 5
    Universal
    Comm.
    Module
    (UCM)
    IRBUS
    Address 6
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Next CMC Panel(s) for
    use in ASC
    Modbus Network #1
    Full or Half Duplex
    RS-422 or RS-485
    DF1 Network
    Full Duplex RS-422A
    Cat5
    Cable
    Ethernet to
    Modbus
    Bridge
    To DH+
    Network
    Allen-Bradley
    1770-KF2
    Interface Module
    140
    CMC TECHNICAL REFERENCE MANUAL
    1770-KF2 Setup
    A 1770-KF2 module links asynchronous devices (RS-422A or RS-232C) to an AllenBradley Data Highway or Data Highway Plus network. The 1770-KF2 module has 8 switch
    assemblies that let you select various communication options. The switch assemblies are
    shown in the diagram below:
    Switch Assembly
    SW-1
    SW-2, SW-3, SW-4
    SW-5
    SW-6
    SW-7
    SW-8
    Communication Option
    Asynchronous link features
    Node number
    Network link communication rate
    Asynchronous link communication rate
    DH/DH+ network link section
    RS-232C/RS-422A selection
    CAUTION
    The 1770-KF2 module reads the status of these communication option
    switches only at power up, so you need to change switch settings with 1770-KF2
    powered off.
    SW-1 (Asynchronous Link Features)
    The following table shows the different combinations available for setting the asynchronous
    link with the 5 dipswitches of SW-1.
    Protocol
    Error
    Check
    Parity
    Embedded
    Response
    1
    2
    Full Duplex
    Full Duplex
    Full Duplex
    Full Duplex
    Full Duplex
    BCC
    BCC
    BCC
    BCC
    CRC
    None
    Even
    None
    Even
    None
    No
    No
    Yes
    Yes
    Yes
    OFF
    ON
    OFF
    ON
    OFF
    OFF
    OFF
    ON
    ON
    ON
    SW-1 Settings
    3
    (Duplicate
    Message)
    ON: ignore
    OFF: accept
    OFF
    OFF
    OFF
    OFF
    OFF
    4
    (Hand
    Shake)
    5
    OFF
    OFF
    OFF
    OFF
    OFF
    OFF
    OFF
    OFF
    OFF
    ON
    CAUTION
    Only the UCM-DF1 driver supports the full duplex options. Half duplex is not
    supported.
    SW-2, SW-3, SW-4 (Node Address)
    These three switch assemblies are used to set the network node number of the 1770-KF2
    module. Set both switches in SW-2 OFF for DH+ link because the node number should be
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    CMC TECHNICAL REFERENCE MANUAL
    a 2-digit octal number that identifies the 1770-KF2 as a unique node on DH+. Valid node
    numbers for 1770-KF2 in DH+ network are 00 to 77 octal.
    First digit (SW-2) should always be set to zero.
    SW-2 Setting
    1
    2
    OFF
    OFF
    OFF
    ON
    ON
    OFF
    ON
    ON
    Digit
    0
    1
    2
    3
    Second and third digits:
    1
    OFF
    OFF
    OFF
    OFF
    ON
    ON
    ON
    ON
    SW-3, SW-4 Setting
    2
    OFF
    OFF
    ON
    ON
    OFF
    OFF
    ON
    ON
    3
    OFF
    ON
    OFF
    ON
    OFF
    ON
    OFF
    ON
    Digit
    0
    1
    2
    3
    4
    5
    6
    7
    SW-5 (Network Link Communication Rate)
    Switch assembly SW-5 lets you select the communication rate for the 1770-KF2 module’s
    network link (DH+). Set both switches ON for a network communication rate of 57,600 bits
    per second. Be sure to set all modules on the same DH+ network for this communication
    rate.
    SW-6 (Asynchronous Link Communication Rate and Diagnostic Commands)
    Switches #1, #2, #3 of SW-6 let you select the communication rate for the 1770-KF2
    module’s asynchronous port. Meanwhile, switch #4 determines how 1770-KF2 module
    treats diagnostic commands sent by a remote DH+ node. It is recommended to set at 9600
    baud or higher, and execute received diagnostic commands.
    Execute received diagnostic commands
    Pass any received diagnostic commands to the attached asynchronous device
    SW-6 Setting
    4
    ON
    OFF
    The available baud rate settings are shown below:
    Baud Rate
    (Bits per second)
    110
    300
    600
    1200
    2400
    4800
    9600
    19200
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    1
    OFF
    ON
    OFF
    ON
    OFF
    ON
    OFF
    ON
    SW-6 Setting
    2
    OFF
    OFF
    ON
    ON
    OFF
    OFF
    ON
    ON
    3
    OFF
    OFF
    OFF
    OFF
    ON
    ON
    ON
    ON
    142
    CMC TECHNICAL REFERENCE MANUAL
    SW-7 (Network Link Selection)
    UCM only supports DH+ network. SW-7 should always select DH+.
    Network
    Mode
    DH
    DH+
    SW-7 Setting
    1
    2
    OFF
    OFF
    ON
    OFF
    SW-8 (RS-232C/RS-422A Selection)
    The UCM-DF1 interface uses RS-422 communication. SW-8 should select RS422.
    Communication
    Type
    RS-232C
    RS-422A
    SW-8 Setting
    1
    2
    OFF
    ON
    ON
    OFF
    Wiring Diagram for RS-422A
    1770 KF2
    Module
    RS-422
    1
    14
    25
    16
    18
    UCM
    RS-422
    GND
    TX+
    TXRX+
    RX-
    Cable not to exceed 4000 feet
    RX+
    RXTX+
    TX-
    4
    5
    6
    8
    20
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    CMC TECHNICAL REFERENCE MANUAL
    143
    Documentation
    An Electrical Schematic drawing is provided as standard after order placement. Control Panel
    Outline drawings are optional. Logic diagrams are considered proprietary and are not available.
    System Information
    Status Codes
    The following table lists the status codes for the Base Control Module (BCM) only. These
    codes indicate every operating condition, both normal and abnormal, for the system. A code
    always exists for the system; for example, Status 05h indicates that the system is running
    properly.
    These codes, except Status 00h and 05h, are shown on a blank screen in the upper left
    hand corner of the Operator User Interface (OUI). Since Status 00h and 05h are normal
    operating conditions, these codes are not displayed. When a code is displayed, contact
    your local Ingersoll-Rand Service Representative.
    Status
    Code
    00h
    Definition
    Booting
    01h
    Stay In Boot
    02h
    ROM CRC Failed
    03h
    Commanded To Boot
    04h
    Invalid Application
    05h
    06h
    Application Running
    Fatal Exit
    07h
    System Error
    08h
    Incompatible Software
    Versions
    A-D System Error
    D-A System Error
    Digital I/O System Error
    Logic Engine System or
    Loop Task Error
    Comparator System Error
    Operator User Interface
    Error
    09h
    0Ah
    0Bh
    0Ch
    0Dh
    0Eh
    0Fh
    Data Logging System Error
    10h
    Low Power
    Comments
    The BCM is in the boot process. This is a normal process during BCM power up.
    This state will not be displayed.
    The BCM is held in boot mode by the hardware configuration. This condition exists
    only when the boot jumper (hardware device) is plugged into the display (OUI) port.
    This hardware jumper is only required when doing system level reprogramming of
    the module.
    The BCM software is not valid. This condition occurs when the CRC (Cyclic
    Redundancy Check) calculated by the module does not equal the CRC value written
    to the module when programmed. This would typically occur when the programming
    process is aborted (halted). The module must be reprogrammed.
    The BCM is currently in the process of being programmed. If this message does not
    disappear after programming is completed, power cycle the unit.
    The BCM software has failed to operate properly. Cycling the power on the module
    will restart the system. Once restarted, the program will operate properly until the
    same condition reoccurs.
    Normal operating condition. This state will not be displayed.
    Operating system error. Cycling the power on the module will restart the system.
    Once restarted, the program will operate properly until the same condition reoccurs.
    Operating system error. Cycling the power on the module will restart the system.
    Once restarted, the program will operate properly until the same condition reoccurs.
    The BCM application software and tables are not compatible. The module must be
    reprogrammed.
    Analog input system error. A hardware malfunction has occurred.
    Analog output system error. A hardware malfunction has occurred.
    Digital input and output system error. A hardware malfunction has occurred.
    Ladder logic processing system or loop task error. The module must be
    reprogrammed.
    Comparator system error. The module must be reprogrammed.
    Operator User Interface system error. Cycling the power on the module will restart
    the system. Once restarted, the program will operate properly until the same
    condition reoccurs.
    Data logging system error. Cycling the power on the module will restart the system.
    Once restarted, the program will operate properly until the same condition reoccurs.
    Power supply voltage (+24 VDC) dropped below minimum operating level. Check
    power supply. Cycle power when voltage is within proper operating limits. Once
    restarted, the program will operate properly until the same condition reoccurs.
    22204796 Rev. B, Version 3.10
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    CMC TECHNICAL REFERENCE MANUAL
    Status
    Code
    11h
    Definition
    Task Overrun
    12h
    Watchdog Failure
    13h
    Intermodule Data Error
    14h
    Calculation Block Error
    15h
    Interpolation System Error
    16h
    Calibration System Error
    Comments
    System processing capabilities do not meet requirements for operation. Cycling the
    power on the module will restart the system. Once restarted, the program will
    operate properly until the same condition reoccurs.
    The internal backup system monitor is not operational. BCM hardware should be
    replaced. Cycling the power on the module will restart the system. Once restarted,
    the program will operate properly until the same condition reoccurs.
    An error has occurred while generating a message to be sent from one BCM to the
    other BCM in a multi-module configuration. The module must be reprogrammed.
    A stack underflow or overflow has occurred in a calculation block. The module must
    be reprogrammed.
    An error has occurred in the interpolation block. The module must be
    reprogrammed.
    Occurs during initialization of the EEPROM block. The module must be
    reprogrammed.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    145
    CMC TECHNICAL REFERENCE MANUAL
    Base Control Module (BCM)
    Module Layout
    J15-Digital Outputs, Channels 4-1
    J14-Digital Outputs, Channels 8-5
    J13-Digital Outputs, Channels 12-9
    J12-Digital Outputs, Channels 16-13
    Pin 1
    J10-Power Input
    (24 VDC)
    Pin 1
    Pin 1
    F102-Fuse for AnalogI/O
    (J1, J2 and J3)
    Pin 1
    J9-Current Transformer
    Input (0-5 Amps)
    Pin 1
    F101-Fuse for Operator
    User Interface (Display)
    F103-Fuse for Digital
    Inputs (J4 and J5)
    F100-Fuse for Base
    Module CPU Card
    J8-Speed Sensor
    Input (1-150 Hz)
    Pin 1
    J7-RS485 Serial
    Data Link (IRBUS)
    Pin 4
    All Fuses are 5x20mm, GMA
    1.5 amp, Fast Blow
    J7-RS232 Serial
    Data Link (Display),
    Pin 1
    J6-RS232 Serial
    Data Link (Display),
    Female DB9
    J5-Digital (Discrete)
    Inputs (24 VDC),
    Channels 9-16
    Pin 1
    J4-Digital (Discrete)
    Inputs (24 VDC),
    Channels 1-8
    Pin 1
    J3-Analog Outputs
    (4-20mA)
    Channels 1-4
    Pin 25
    Pin 7
    Pin 1
    Pin 5
    Pin 1
    Pin 1
    J1-Grounded Analog Inputs,
    (4-20mA) Channels 3-23
    J2-Floating Analog Inputs, (4-20mA) Channels 1-2
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    146
    CMC TECHNICAL REFERENCE MANUAL
    Connector Description
    Tag
    Type
    Channel
    Module Connector
    Mating Connector
    J1
    Grounded Analog Inputs, 4-20 mA
    3-23
    (2) Phoenix MDST
    2, 5/24-3T-5, 08
    J2
    Floating Analog Inputs, 4-20 mA
    1-2
    J3
    Analog Outputs, 4-20 mA
    1-4
    J4
    J5
    J6
    Digital (Discrete) Inputs, 24 VDC
    1-8
    9-16
    na
    (12) Phoenix
    MDSTB 2, 5/2-G-5,
    08
    (2) Phoenix MDSTB
    2, 5/2-G-5, 08
    (3) Phoenix MDSTB
    2, 5/2-G-5, 08
    Phoenix MSTBA 2,
    5/10-G-5, 08
    9 Position “D” Sub
    Miniature (Female)
    Phoenix MSTBA 2,
    5/9-G-5, 08
    Phoenix MSTBA 2,
    5/3-G-5, 08
    Terminal Strip
    Phoenix MSTBA2,
    5/5-G-5, 08
    (4) Phoenix MSTBA
    2, 5/8-G-5, 08
    J7
    J8
    J9
    J10
    J12
    J13
    J14
    J15
    RS232 Serial Data Link (Operator
    User Interface)
    RS232 Serial Data Link (OUI)
    RS485 (IRBUS) Serial Data Link
    Speed Sensor Input, Variable
    Reluctance
    Current Transformer Input
    Power
    Digital Outputs
    na
    na
    na
    13-16
    9-12
    5-8
    1-4
    (2) Phoenix MDST
    2, 5/4-3T-5, 08
    (2) Phoenix MDST
    2, 5/6-3T-5, 08
    Phoenix MSTB 2,
    5/10-ST-5, 08
    9 Position “D” Sub
    Miniature (Male)
    Phoenix MSTB 2,
    5/5-ST-5, 08
    Phoenix MSTB 2,
    5/3-ST-5, 08
    Wire Lugs
    Phoenix MSTB 2,
    5/5-ST-5, 08
    (4) Phoenix MSTB
    2, 5/8-ST-5, 08
    NOTES:
    1. BCM Weight: 1775 ± 177g [3.92 ± .39 lb.]
    2. BCM Size: Length=355.6 mm [14.0 in] x Width=247 mm [9.7 in] x Depth=45 mm [1.8 in]
    3. To ensure chassis ground, install 12-gauge ground strap between this module and the
    NEMA enclosure. Place external tooth lock washer between this module and the ground
    strap.
    4. “na” is defined as “not applicable”.
    5. All Phoenix connectors may be replaced with an equal supplier.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    147
    CMC TECHNICAL REFERENCE MANUAL
    Connector Input and Output (I/O)
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    J1-Grounded Analog Inputs
    Analog Input Channel 3
    Power 24 VDC, Channels 3 & 4
    Shield, Channels 3 & 4
    Analog Input Channel 4
    Analog Input Channel 5
    Power 24 VDC, Channels 5 & 6
    Shield, Channels 5 & 6
    Analog Input Channel 6
    Analog Input Channel 7
    Power 24 VDC, Channels 7 & 8
    Shield, Channels 7 & 8
    Analog Input Channel 8
    Analog Input Channel 9
    Power 24 VDC, Channels 9 & 10
    Shield, Channels 9 & 10
    Analog Input Channel 10
    Analog Input Channel 11
    Power 24 VDC, Channels 11 & 12
    Shield, Channels 11 & 12
    Analog Input Channel 12
    Analog Input Channel 13
    Power 24 VDC, Channels 13 & 14
    Shield, Channels 13 & 14
    Analog Input Channel 14
    Analog Input Channel 15
    Power 24 VDC, Channels 15 & 16
    Shield, Channels 15 & 16
    Analog Input Channel 16
    Analog Input Channel 17
    Power 24 VDC, Channels 17 & 18
    Shield, Channels 17 & 18
    Analog Input Channel 18
    Analog Input Channel 19
    Power 24 VDC, Channels 19 & 20
    Shield, Channels 19 & 20
    Analog Input Channel 20
    Analog Input Channel 21
    Power 24 VDC, Channels 21 & 22
    Shield, Channels 21 & 22
    Analog Input Channel 22
    Analog Input Channel 23
    Power 24 VDC, Channel 23
    Shield, Channel 23
    Spare
    Spare
    Power 24 VDC, Spare
    Shield, Spare
    Spare
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    J2-Floating Analog Inputs
    Analog Input Channel 1+
    Power 24 VDC, Channel 1
    Analog Input Channel 1Shield, Channel 1
    Analog Input Channel 2+
    Power 24 VDC, Channel 2
    Analog Input Channel 2Shield, Channel 2
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    J3-Analog Outputs
    Analog Output Channel 1+
    Power 24 VDC, Channels 1 & 2
    Analog Output Channel 1Analog Output Channel 2+
    Shields, Channels 1 & 2
    Analog Output Channel 2Analog Output Channel 3+
    Power 24 VDC, Channels 3 & 4
    Analog Output Channel 3Analog Output Channel 4+
    Shields, Channels 3 & 4
    Analog Output Channel 4-
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    J4-Digital Inputs
    Power 24 VDC, Channels 1-8
    Digital Input Channel 1
    Digital Input Channel 2
    Digital Input Channel 3
    Digital Input Channel 4
    Digital Input Channel 5
    Digital Input Channel 6
    Digital Input Channel 7
    Digital Input Channel 8
    Ground, Channels 1-8
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    J5-Digital Inputs
    Power 24 VDC, Channels 9-16
    Digital Input Channel 9
    Digital Input Channel 10
    Digital Input Channel 11
    Digital Input Channel 12
    Digital Input Channel 13
    Digital Input Channel 14
    Digital Input Channel 15
    Digital Input Channel 16
    Ground, Channels 9-16
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    9
    J6-RS232 (Display)
    Not Used
    Receive Data (RxD)
    Transmit Data (TxD)
    Not Used
    Signal Ground
    Not Used
    Not Used
    Not Used
    Not Used
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    9
    J7-RS232 (Display) / RS485 (IRBUS)
    Receive Data (RxD)
    (Display)
    Transmit Data (TxD)
    (Display)
    Signal Ground
    (Display)
    Data Link 1+
    (IRBUS)
    Data Link 1(IRBUS)
    Data Link Ground (IRBUS)
    Data Link 1+
    (IRBUS)
    Data Link 1(IRBUS)
    Data Link Ground (IRBUS)
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Pin
    1
    2
    3
    J8-Speed Sensor
    SS+
    SSSS Ground
    Pin
    1
    2
    J9-Current Transformer
    CT+
    CT-
    Pin
    1
    2
    3
    4
    5
    J10-Power
    Power +24V DC
    Power Ground
    Chassis Ground
    Display Power +24VDC
    Display Power Ground
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    J12-Digital Outputs
    Digital Output Channel 16
    Digital Output Channel 16
    Digital Output Channel 15
    Digital Output Channel 15
    Digital Output Channel 14
    Digital Output Channel 14
    Digital Output Channel 13
    Digital Output Channel 13
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    J13-Digital Outputs
    Digital Output Channel 12
    Digital Output Channel 12
    Digital Output Channel 11
    Digital Output Channel 11
    Digital Output Channel 10
    Digital Output Channel 10
    Digital Output Channel 9
    Digital Output Channel 9
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    J14-Digital Outputs
    Digital Output Channel 8
    Digital Output Channel 8
    Digital Output Channel 7
    Digital Output Channel 7
    Digital Output Channel 6
    Digital Output Channel 6
    Digital Output Channel 5
    Digital Output Channel 5
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    J15-Digital Outputs
    Digital Output Channel 4
    Digital Output Channel 4
    Digital Output Channel 3
    Digital Output Channel 3
    Digital Output Channel 2
    Digital Output Channel 2
    Digital Output Channel 1
    Digital Output Channel 1
    148
    CMC TECHNICAL REFERENCE MANUAL
    Operator User Interface Module (OUI)
    Module Layout
    Side View
    J1-RS232 Port
    Pin 1
    J3-RS232 Port
    Pin 1
    Pin 1
    J2-Input Power
    Connector Description
    Tag
    Type
    J1
    RS232 Port
    J2
    Input Power
    J3
    RS232 Port
    Module Connector
    Mating Connector
    9 Position “D” Sub
    Miniature (Female)
    Phoenix MSTBA2,
    5/2-G-5, 08
    Phoenix MC 1.5/5G-3.81
    9 Position “D” Sub
    Miniature (Male)
    Phoenix MSTW2,
    5/2-ST-5, 08
    Phoenix MC 1.5/5ST-3.81
    NOTES:
    1. OUI Weight: 410 g [0.90 lb.]
    2. OUI Size: Length=267 mm [10.5 in] x Width=175 mm [6.9 in] x Depth=60 mm [2.4 in]
    3. All Phoenix connectors may be replaced with an equal supplier.
    Connector Input and Output (I/O)
    Pin
    1
    J1-RS232 Port
    No Connection
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    9
    Transmit (TX)
    Receive (RX)
    No Connection
    Signal Common
    No Connection
    No Connection
    No Connection
    No Connection
    2
    J2-Input Power
    +12 To +24 VDC
    (VPOWER)
    Ground (GND)
    Pin
    1
    J3-RS232 Port
    RS232 Data Link Tx
    2
    3
    4
    5
    RS232 Data Link Rx
    Common (Com)
    IRBUS RS485 Data Link (DL+)
    IRBUS RS485 Data Link (DL-)
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    149
    CMC TECHNICAL REFERENCE MANUAL
    OUI PCB Assembly (Cover Removed)
    Showing replaceable fuse
    J1
    9 Position
    "D" Sub
    Connector
    Fast-Acting, SMF, .75A, 125V
    Littlefuse 0451.750 or 0453.750
    or Equivalent
    J3
    5 Pin
    Connector
    F2
    J2
    2 Pin
    Connector
    CMC User Interface/Bezel Cleaning Instructions
    The following procedure is recommended to clean the CMC User Interface vinyl overlay
    material and/or the User Interface bezel.
    1. Stop the compressor and depress the maintained ‘Emergency Stop’ push-button, this
    will prevent an inadvertent start up or trip of the compressor during the cleaning
    process.
    2. Dampen a soft cloth or paper towel with water and wipe any dust, dirt or liquids from the
    surface of the User Interface, do not use an abrasive pad or brush to clean the surface
    of the User Interface vinyl overlay or bezel.
    3. If more aggressive measures are required to clean the User Interface and/or bezel
    surface use a mild non-abrasive household cleaner (such as Formula 409, Fantastik,
    etc.) sprayed or wiped directly onto the surface to be cleaned. Dampen a soft cloth or
    paper towel with water and wipe any remaining cleaner from the surfaces.
    Ingersoll-Rand Company recommends the following for cleaning the OUI and bezel:
    Cleaners: Water or mild household cleaner, no petroleum or acetone based fluids.
    Cleaning wipes: Soft cotton clothe or paper towels.
    Backlight Replacement Procedure
    Tools Needed:
    1. Flat blade screwdriver with a small tip (1/8 inch)
    2. Number 1 Phillips Screwdriver
    3. Electrostatic Discharge Strap Connected to Earth Ground
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    150
    CMC TECHNICAL REFERENCE MANUAL
    Step 1
    J1
    User
    Terminal
    J3
    User
    Terminal
    Tx
    Rx
    COM
    DL+
    DL-
    Lift cover to remove
    J2
    Loo
    s
    +
    en
    scr
    ew
    s, s
    l
    ide
    righ
    Step 2
    Remove
    cabling
    Unplug connector
    and remove nylon
    cable retainer screws
    Display
    Power
    t
    Step 3
    Step 4
    Remove screws from the
    lower printed circuit
    board, then use a
    screwdriver to gently pry
    the backlight panel loose.
    Use circular stand-offs to
    rest screwdriver shaft
    against while prying
    backlight panel out.
    The backlight is part of a larger panel
    that is removed as an assembly.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    151
    CMC TECHNICAL REFERENCE MANUAL
    Step 5
    Step 6
    Backlight panel is
    inserted into display
    between the circuit board
    and the LCD glass with
    the white plastic backing
    sheet and wires facing
    toward the circuit boards.
    Slide the backlight panel
    in place and align the
    screw holes so the screws
    may be inserted and
    tightened.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Insert screws being careful
    not to over tighten.
    Route wiring, replace nylon cable retainers,
    insert backlight plug, replace main cover
    and connect power and communication
    cable to complete installation.
    152
    CMC TECHNICAL REFERENCE MANUAL
    Universal Communication Module (UCM) Optional
    Module Layout
    Side View
    J2-Service/Modem
    (RS232) Port
    J1-Microcontroller/Network
    (RS422/RS485) Port
    Pin 1
    J3-Input Power
    Pin 1
    Pin 1
    Top View
    RS232 Activity
    Indicator
    IRBUS RS485
    Activity Indicator
    RS422/485 Activity Indicator
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    153
    CMC TECHNICAL REFERENCE MANUAL
    Connector Description
    Tag
    Type
    Module Connector
    Mating Connector
    J1
    Microcontroller/Network
    (RS422/485) Port
    Phoenix MSTBA2,
    5/8-G-5, 08
    Phoenix MSTBW2,
    5/24-ST-5, 08
    J2
    Service/Modem (RS232)
    Port
    9 Position “D” Sub
    Miniature (Female)
    9 Position “D” Sub
    Miniature (Male)
    J3
    Input Power
    Phoenix MSTBA2,
    5/2-G-5, 08
    Phoenix MSTW2,
    5/2-ST-5, 08
    NOTES:
    1. UCM Weight: 410 g [0.90 lb.]
    2. UCM Size: Length=136 mm [5.4 in] x Width=143 mm [5.6 in] x Depth=31 mm [1.2 in]
    3. All Phoenix connectors may be replaced with an equal supplier.
    Connector Input and Output (I/O)
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    J1-Microcontroller/Network Port
    IRBUS RS485 Datalink + (DL+)
    IRBUS RS485 Datalink - (DL-)
    Ground (GND)
    RS422/485 Transmit + (TX+)
    RS422/485 Transmit - (TX-)
    RS422/485 Receive + (RX+)
    RS422/485 Receive - (RX-)
    Ground (GND)
    Pin
    1
    2
    3
    4
    5
    6
    7
    8
    9
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    J2-Service/Modem Port
    No Connection
    Transmit (TX)
    Receive (RX)
    No Connection
    Signal Common
    No Connection
    No Connection
    No Connection
    No Connection
    Pin
    1
    2
    J3-Input Power
    +12 To +24 VDC (VPOWER)
    Ground (GND)
    154
    CMC TECHNICAL REFERENCE MANUAL
    UCM Port Activity LEDs
    The UCM has three light emitting diodes (LEDs) to indicate the activity of the RS232,
    RS422/485 and the IRBUS RS485 ports. The following table indicates the different states of
    these ports.
    RS232
    off
    on
    RS422
    RS485
    off
    off
    IRBUS
    RS485
    off
    off
    on
    on
    blinking
    blinking
    on
    on
    on
    on
    on
    blinking
    blinking
    on
    on
    on
    blinking
    blinking
    blinking
    on
    blinking
    blinking
    blinking
    UCM State
    No power (24 VDC)
    Boot mode, check A1 switch for being non-zero (cycle
    power to exit boot mode)
    Running, but no communication on any port
    Multi-module job with inter-module communication
    Service Tool in use
    Service Tool in use, but no response from BCM … check
    connection between BCM and UCM
    MODBUS communication in use
    RS-422 port in use, but no response from BCM … check
    connection between BCM and UCM or Modbus and DF1
    address
    All blinking together imply a continuous reboot or application
    problem
    UCM Communications Parameters
    The UCM has three communication ports, RS232, RS422/485 and IRBUS RS485. Each of
    these ports has its own communication parameters that it supports.
    Service Tool
    RS-232
    50 feet (15.2 meters)
    9600
    Modbus/DF1
    IRBUS
    Parameter
    RS-422/485
    RS-485
    Distance
    4000 feet (1218.3 Meters) 100 feet (30.4 Meters)
    Baud Rate
    300, 600, 1200, 2400,
    9600
    9600, 19200, 38400
    Parity
    None
    None, Even, Odd
    None
    Data Bits
    8
    8
    8
    Stop Bits
    1
    1, 1.5, 2
    1
    Configurable No
    Yes*
    No
    * A certified Ingersoll-Rand Service Representative will provide this configuration.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    155
    CMC TECHNICAL REFERENCE MANUAL
    RS422/485 Network Wiring Diagram - Full Duplex
    SERVER
    (Modbus Master)
    Compressor Panel #n
    Modbus Address - nn
    IRBUS Address - any
    120 VAC
    To Server's
    Network Card
    Ethernet
    Switch
    Ethernet
    Cable
    Cat5 or
    Better
    Compressor Panel #6
    Modbus Address - 06
    IRBUS Address - any
    Compressor Panel #5
    A terminating resistor
    is not required at the
    end of the network.
    Modbus Address - 05
    IRBUS Address - any
    Rx- Rx+ Tx+ Tx-
    Ethernet /
    Modbus
    Bridge
    The maximum
    distance of a
    MODBUS Network is
    4000 electrical feet;
    i.e., the length of the
    wire from the Ethernet
    Bridge (Location A) to
    the last compressor's
    Universal
    Communication
    Module (Location B).
    The maximum number
    of devices (nodes) on
    a MODBUS Network is
    30.
    3 Com
    120 VAC
    B
    Compressor Panel #4
    RS-422
    2 Twisted Pair Wires
    with Ground (5 Wires)
    Modbus Address - 04
    IRBUS Address - any
    174 CEV
    300
    Compressor Panel #3
    24VDC +
    Fused -
    Modbus Address - 03
    IRBUS Address - any
    RS-422
    2 Twisted
    Pair Wires
    Plus Gnd.
    (5 Wires)
    Connect
    Ground
    One End
    Only
    To
    Power
    Supply
    24+ Gnd
    Power
    To
    Power
    Supply
    To
    BCM
    DL+ DL- Gnd Tx+ Tx- Rx+ Rx- Gnd
    RS-485
    RS-422/485
    RS-232
    DB-9
    Universal Communication Module (UCM)
    Modbus Address - 01
    (Set through software)
    Compressor Panel #1
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    RS-422
    2 Twisted
    Pair Wires
    with Ground
    (5 Wires)
    24+ Gnd
    Power
    To
    BCM
    DL+ DL- Gnd Tx+ Tx- Rx+ Rx- Gnd
    RS-485
    RS-422/485
    RS-232
    DB-9
    Universal Communication Module (UCM)
    Modbus Address - 02
    (Set through software)
    Compressor Panel #2
    156
    CMC TECHNICAL REFERENCE MANUAL
    RS422 Network Wiring Diagram - Half Duplex
    SERVER
    (Modbus Master)
    Compressor Panel #n
    Modbus Address - nn
    IRBUS Address - any
    120 VAC
    To Server's
    Network Card
    Ethernet
    Switch
    Ethernet
    Cable
    Cat5 or
    Better
    Compressor Panel #6
    The maximum
    distance of a
    MODBUS Network is
    4000 electrical feet;
    i.e., the length of the
    wire from the Ethernet
    Bridge (Location A) to
    the last compressor's
    Universal
    Communication
    Module (Location B).
    The maximum number
    of devices (nodes) on
    a MODBUS Network is
    30.
    3 Com
    Modbus Address - 06
    IRBUS Address - any
    120 VAC
    B
    Compressor Panel #5
    A terminating resistor
    is not required at the
    end of the network.
    Modbus Address - 05
    IRBUS Address - any
    Rx- Rx+ Tx+ Tx-
    Compressor Panel #4
    Ethernet /
    Modbus
    Bridge
    RS-422
    Twisted Pair Wires
    with Ground (3 Wires)
    Modbus Address - 04
    IRBUS Address - any
    174 CEV
    300
    24VDC +
    Fused -
    Compressor Panel #3
    A
    Modbus Address - 03
    IRBUS Address - any
    RS-422
    Twisted Pair
    Wires
    With Ground
    (3 Wires)
    Connect
    Ground
    One End
    Only
    To
    Power
    Supply
    24+ Gnd
    Power
    To
    BCM
    DL+ DL- Gnd Tx+ Tx- Rx+ Rx- Gnd
    RS-485
    RS-422/485
    RS-232
    DB-9
    Universal Communication Module (UCM)
    Modbus Address - 01
    (Set through software)
    Compressor Panel #1
    RS-422
    Twisted Pair
    Wires with
    Ground (3
    Wires)
    To
    Power
    Supply
    24+ Gnd
    Power
    To
    BCM
    DL+ DL- Gnd Tx+ Tx- Rx+ Rx- Gnd
    RS-485
    RS-422/485
    RS-232
    DB-9
    Universal Communication Module (UCM)
    Modbus Address - 02
    (Set through software)
    Compressor Panel #2
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    CMC TECHNICAL REFERENCE MANUAL
    157
    Terminating Resistor – Modbus Network
    The RS422/485 circuitry built into each UCM supports Alternate-Fail-safe AC Termination.
    This termination circuitry enhances the UCM's ability to operation in harsher (electrically
    noisier) environments. Since this circuitry is built into the product, no external terminating
    resistor is required. For a thorough discussion of the various termination techniques, please
    refer to "A Comparison of Differential Termination Techniques", National Semiconductor
    Application Note 903 (AN-903), August 1993. This application note can be obtained from
    the Internet at "www.national.com".
    Terminating Resistor – IRBUS Network
    Due to the data rate the RS485 IRBUS is provided with termination resistors mounted
    inside the panel. The value of each resistor is 470 ohms. The purpose of the termination is
    to prevent reflections. Reflections occur when a signal encounters different impedance and
    is reflected back towards the source. This can corrupt the intended data transmission.
    Where IRBUS is networked with other panels two termination resistors are required, one at
    each end of the network.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    158
    CMC TECHNICAL REFERENCE MANUAL
    Typical System Layout
    Operator User Interface (OUI)
    CENTAC 
    Microcontroller
    24 VDC Power
    RS232
    Base Control Module
    (BCM) #1
    470
    ohm
    IRBUS OUT
    IRBUS IN
    IRBUS (RS485)
    IRBUS (RS485)
    24 VDC
    120/240 VAC
    Power
    Universal
    Communications
    Module (UCM)
    Base Control Module
    (BCM) #2
    Power Supply
    24 VDC
    Service Tool
    Port Not Shown
    24 VDC
    Optional
    Equipment
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    159
    CMC TECHNICAL REFERENCE MANUAL
    Network Diagram
    CMC Panel
    CENTAC  Microcontroller
    RS-232 Network for
    Operator User Interface,
    Twisted Pair Wires with
    Common (3 Wires)
    IRBUS (RS-485) Network
    for Base Control Modules
    and Universal
    Communication Modules,
    Twisted Pair Wires with
    Ground (3 Wires)
    Base
    Control
    Module
    (BCM)
    IRBUS
    Address: 1
    Serial Port
    (COM1)
    INGERSOLL-RAND
    Service Tool
    470
    ohm
    IRBUS IN
    (For IR Use)
    IRBUS OUT
    (For IR Use)
    Base
    Control
    Module
    (BCM)
    Service Tool
    Plug on
    Panel Door
    Universal
    Communication
    Module (UCM)
    IRBUS
    Address 4
    Network Card
    Comm Port on
    Server
    IRBUS
    Address: 2
    INGERSOLL-RAND
    Air System Controller
    (ASC)
    Universal
    Comm.
    Module
    (UCM)
    IRBUS
    Address 5
    Universal
    Comm.
    Module
    (UCM)
    IRBUS
    Address 6
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Next CMC Panel(s) for
    use in ASC
    Modbus Network #1
    Full or Half Duplex
    RS-422 or RS-485
    Modbus Network #2
    Full or Half Duplex
    RS-422 or RS-485
    Cat5
    Cable
    Ethernet to
    Modbus
    Bridge
    To next CMC Panel
    or any other
    Modbus compliant
    product
    160
    CMC TECHNICAL REFERENCE MANUAL
    Technical Specification
    DESCRIPTION OF STANDARD
    Switches, Lights and Push Buttons
    Control Power On/Off switch... activates panel power and prelube pump
    Compressor trouble light (red)
    Emergency stop pushbutton
    Microprocessor OUI
    240x128 pixel LCD graphic display window
    Tabbed folders for ease of navigation
    Status Bar with compressor state
    Eighteen screens of compressor information and setup data
    Left/Right/Up/Down/Return push buttons
    Acknowledge/Reset push buttons
    Start/Stop push buttons
    Load/Unload push buttons
    Contrast Button
    Event Log
    Most recent 224 events with name, time, date and value
    Logged events
    Alarms
    Trips
    Command key press (local and remote)
    E-Stop pressed
    Module control power up and down
    MinLoad reset
    Analog input failed
    Setpoint change (local and remote)
    Automatic start and stop (when Auto Hot Start purchased)
    Surge Unload
    Compressor Started
    Driver Failed to Start
    Loss of Motor Power
    Language and Units of Measure
    Language and Units of Measure Sets
    Two Language and Units of Measure sets are select-able from the display.
    NOTE: The English language and psia, degF, mils are standard for all
    units. English and kPA, degC, microns are the default alternate
    language unless otherwise specified. Other Units of Measure are
    available upon request.
    Languages
    Arabic
    Bulgarian
    Chinese
    Croatian
    Czech
    Danish
    Dutch
    French
    Finnish
    German
    Greek
    Hungarian
    Italian
    Norwegian
    Polish
    Portuguese
    Romanian
    Russian
    Slovakian
    Slovenian
    Spanish
    Swedish
    Turkish
    Units of Measure
    Available upon request.
    Control Functions
    Modulate or Autodual
    Manual Valve control for compressor setup
    High motor load limit (controls maximum opening of inlet valve)
    MinLoad (controls minimum opening of inlet valve)
    Partial Unload on Surge
    Moves inlet valve to minimum load setting and bumps the bypass valve
    open to exit the surge condition
    Minimizes duration and magnitude of pressure drop from surge
    Surge Indexing
    Actual/Alarm/Trip Functions
    Low oil pressure
    High/low oil temperature
    High air temperature into last compression stage
    High stage shaft vibrations, single plane
    Alarm Function
    Surge
    Trip Function
    Low seal air (interlocked w/ prelube pump operation)
    PHYSICAL DATA
    Panel Construction
    NEMA 12 enclosure
    Formed and welded 11-gauge carbon steel cabinet, 14 gauge door
    Door gasket with butt type hinges
    Back panel for component mounting
    Dimensions
    Panel1
    Panel2
    Height
    54 in (137.2 cm)
    54 in (137.2 cm)
    Width
    32 in (81.3 cm)
    35 in (88.9 cm)
    Depth
    12 in (30.5 cm)
    14 in (35.6 cm)
    1 - No Starter or size 5 starter panels
    2 - with size 5DP or size 6 starter panels
    Controller Board
    14.0 in (35.5 cm)
    9.7 in (24.6 cm)
    1.0 in (2.5 cm)
    Weight
    Without starter 300 lb. (136.1 kg)
    With size 5 starter 350 lb. (158.8 kg)
    With size 6 starter 375 lb. (170.1 kg)
    Component Data
    Canadian Standard Association (CSA)
    Underwriters Laboratories (UL) approved components
    Control Wiring
    High voltage and low voltage wiring segregation
    TEW wire with PVC insulation (meets NEMA VM-1 for Flame
    Retardant
    105 degC temperature rise on insulation
    600 V rating, 18 gauge for instrumentation and signal, 16 gauge for
    control
    Heat shrink wire markers for harness
    Clip-on wire markers internal to panel
    Wire Ferules
    Terminal Blocks
    300 VAC design for #22 through #10 wire size
    Tubular clamp contacts and tang clamping collar, DIN Rail mounted
    Push Buttons/Selector Switches/Indicating Lights
    Corrosion resistant, Oil-tight
    Designed and manufactured to NEMA 4/12/13
    Pilot lights are 120 VAC full voltage type
    Control Interposing Relays
    Two normally open and Two normally closed contacts rated:
    1/3HP 10AMP 120VAC
    1/2HP 10AMP 240VAC
    10AMP 28VDC
    Coil rated 120 VAC
    Contacts
    Normally Open, 5 amps at 120 VAC
    Pressure Transducers
    Ranges 0-50 PSIG, 0-200 PSIG, 0-500 PSIG, 4-20 mA Output
    Channel
    7/16-20 SAE or 1/4" NPT pressure port fitting
    Hirschmann GSA3000N connection head fitting for machine mounted
    model
    Temperature Transducers
    0-500 degF operating range, 4-20 mA transmitter
    100 ohm platinum, TCR=0.00385
    Four compression type terminals
    NEMA 4 rating
    Vibration Transmitters
    Eddy current probe
    Vibration range 0-4 mils, Frequency range 5-3000 Hz
    Output Channel 4-20 mA and 200 mV/Mil, Supply voltage 18-50 VDC
    Barrier type screw terminals, DIN rail mountable
    Hardened against 150 MHz and 440 MHz radio interference
    Wiring Harness
    One wiring harness per device
    NEMA 4 rated
    Display Functions (Read Only)
    Motor current
    System air pressure
    Copper Ground Bar
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    161
    CMC TECHNICAL REFERENCE MANUAL
    OPTIONS
    Analog Inputs (Monitor, Alarm and Trip)
    Any Temperature
    Any Pressure
    Any Vibration
    Any 4-20 mA signal
    Digital (Discrete) Inputs (Monitor and Alarm or Trip)
    Low water flow
    Dirty inlet filter (switch supplied loose)
    Dirty oil filter
    Low oil level
    High condensate level (common for all traps)
    High motor temperature
    Any Discrete Input
    Panel Enclosures
    Cooing Fan with Filter
    110/115 VAC, 50/60 Hz, 0.24 Amps, 20 Watts
    Air flow with filter 36 CFM (61 M3/Hr)
    NEMA 4 Enclosure
    Space Heater, Vortex Tube Cooler
    NEMA 4X Enclosure
    Space Heater, Vortex Tube Cooler
    Stainless steel or epoxy coated carbon steel
    Space Heater
    120 VAC, 120 Watts, finned strip heater
    Bimetallic baseboard type thermostat set at 45 degF (7 degC)
    Vortex Tube Cooler
    25 SCFM (42 NM3/Hr) at 100 PSIG (7 BarG) of compressed air
    1500 BTU/Hr (378 kCal/Hr), Thermostat set at 90 degF (32 degC)
    Solenoid operated valve, Air Filter
    Type Z Purge
    Select-able quick and normal flow rates with meters
    Differential pressure switch set at 0.2 inches (5 mm) of water
    Loss of purge indication, Relief valve, Warning label
    Fused Control Power Disconnect
    Rotary handle through door, 30 amp fuse
    Ground Fault Protector for UL Panels
    120 Vac circuits protected against ground fault currents.
    Control Electrical Package (Standard on CV)
    Prelube Pump Motor Starter
    Two horsepower and less
    Available voltages 380, 460, 575 VAC
    Maximum voltage rating 600 VAC, 10 Amp rating, 120 VAC coils
    IEC Style
    Heater Contactor
    IEC Style, Adjustable ambient compensated overloads
    Available voltages 380, 460, 575 VAC
    Maximum voltage rating 600 VAC, 10 Amp rating, 120 VAC coils
    Control Power Transformer
    Machine tool type, 230, 460, 575 VAC to 120/95 VAC
    500 VA or optional 1000 and 1500 VA, 50 or 60 Hz
    Transient Voltage Surge Suppressor
    UL 1449 Listed
    Tested to ANSI / IEEE C62.41 category A and B environments.
    Stage Data Package (Standard on CV)
    Interstage Air Pressure and Temperature each stage
    Alarm Horn
    80-95 dBA, 2900 Hz
    Running Unloaded Shutdown Timer
    Timing range and mode select-able through CMC
    Water Solenoid Post Run Timer
    Timing range and mode select-able through CMC
    Inlet Valve Tight Closure
    Keeps inlet valve closed until motor reaches full speed
    0-30 second timer range settable by IR Service Tech
    Diesel Engine Driven Compressor Control
    Steam and Gas Turbine Driven Compressor Control
    Main Motor Starter (Wye-Delta)
    NEMA Size 5 or 6
    Open transition type, Ambient compensated overloads
    Available voltages 380, 460, 575 VAC, 120 VAC coils
    Power Regulating Transformer
    120 VAC, 60 Hz, 250 VA
    -65% Input Channel line variation, Output Channel +5-10% NEMA
    Specification
    ±15% Input Channel line variation, Output Channel ±3%
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Automatic Starting
    Automatic Hot Start
    REMOTE FUNCTIONS DISABLED/ENABLED Selector Switch
    Solenoid Valves for Intercoolers
    CMC settable start up pressure setpoint
    Post Run Water Flow Timer
    Automatic Cold Start
    CONTROL POWER LOCAL/OFF/ COLD Selector Switch
    Strobe Light
    Solenoid Valves for Intercoolers and Instrument Air Line
    CMC settable start up pressure setpoint
    Post Run Water Flow Timer
    Start Timer
    Lube Oil Alarm Bypass Timer
    COMMUNICATIONS OPTIONS
    Communications Card(s)
    Up to three cards per module RS-422/485
    Local/Network Selector Switch
    Direct CMC Communication with RS422/RS-485
    Requires programming application by customer
    Utilizes standard MODBUS protocol or Allen-Bradley DF1 protocol for
    PLC2, PLC5 and SLC500 devices
    Hard Wired Communication
    REMOTE FUNCTIONS DISABLED/ENABLED Selector Switch
    Contacts for Remote Start/Stop, Load/Unload, Acknowledge/Reset
    Trouble Indication Contacts (Alarm and Trip, Alarm Only or Trip Only)
    Remote 4-20 for Pressure Setpoint
    Running Unloaded Contact
    Air System Controller (ASC)
    Features
    Sequencing, load sharing and energy management for eight (8)
    compressors (more depending on network design and hardware)
    A CMC Communication Adapter mounted in each CMC panel
    Max distance from last compressor to Communication Adapter is 4000
    feet (1218 meters)
    Modbus to Ethernet Bridge
    Ethernet Switch
    ASC Personal Computer (running Server Software)
    Pentium IV processor (Minimum 1.4GHz microprocessor)
    256 MB RAM (512 Recommended)
    144 MB 3.5 inch diskette drive
    Network Interface card
    Recordabel/Rewriteable CD ROM Drive
    144 MB 3.5 inch diskette drive
    Minimum 40.0 GB hard drive
    CUSTOMER RESPONSIBILITIES
    Three phase power
    Clean, dry control air 80-150 PSIG (5.62-10.55 kg/cm2)
    Control air tubing from control air header, 1/4 in (0.635 cm) FNPT
    connection
    Mount and wire external switches and field wired devices
    Tuning control parameters for system
    Current transformer – instrument grade
    0-5 amp
    Better than 1% accuracy
    CONTROLLER OPERATING ENVIRONMENT
    Electrical Operation
    115 VAC ±5%
    24 VDC Instruments except three wire RTDs
    32 VA of AC power requirement
    50/60 Hz AC supply frequency
    Temperatures
    Operating temperature 32 to 140 degF (0 to 60 degC)
    Storage temperature -4 to 158 degF (-20 to 70 degC)
    Relative Humidity
    95% (maximum) non-condensing
    DOCUMENTATION
    Instruction book
    Electrical schematic
    Panel Outline drawing (Optional)
    CMC TECHNICAL REFERENCE MANUAL
    Glossary
    The following glossary is generic; therefore,
    some terms do not apply to all CMC systems.
    AB — See Allen-Bradley.
    Absolute Address — For Modbus compliant devices, the
    specific memory location for a coil, discrete input, register or
    analog input. The address is a five-digit number.
    Accelerometer — An instrument used to measure
    acceleration. These instruments are typically used for bearing
    analysis.
    Actuator — The device on a control valve that provides the
    power to move the valve to a position. Typically, this power is
    supplied through control air to open (for the inlet valve) and
    close (for the bypass valve). For “fail-safe” operation, a spring
    is used to drive the valve in the opposite direction.
    Address — This term is used by PLC manufacturers to
    indicate a specific memory location within the unit. These
    locations typically reference the value for data items like analog
    inputs, analog outputs, digital inputs, digital outputs, coils and
    intermediate computational states. Through these memory
    locations, the current system pressure, first stage vibration and
    discharge air temperature can be determined.
    Alarm — The term used to indicate that an abnormal condition
    exists that should be addressed by an operator. This condition
    has not reached a level that would shut down the compressor.
    Alert — See Alarm.
    Allen-Bradley — A manufacturer of control products, most
    notably PLCs. These PLCs are used for various industrial
    applications including controlling compressors.
    American Wire Gage (AWG) — The measurement system
    used to indicate the diameter of the wire. The gage number
    increases as the wire diameter decreases.
    Ambient Control — See Polytropic Head.
    Analog Input — An electrical device, which represents a
    specific real world pressure, temperature, vibration or current.
    As these items fluctuate, the electrical signal to and from the
    microprocessor board also fluctuates proportionally to the
    amount of change. The electrical signal is typically in the form
    of a current that ranges from 4 to 20 milli-amps in magnitude.
    Analog Output — An electrical signal, which typically
    represents the inlet and bypass valve position. As these valves
    fluctuate, the electrical signal to and from the microprocessor
    board also fluctuates proportionally to the amount of change.
    The electrical signal is typically in the form of a current that
    ranges from 4 to 20 milli-amps in magnitude.
    Auto-Cold Start — A control mode that automatically
    energizes the panel power, opens cooling water flow valve to
    the coolers, turns on seal air, starts and loads the compressor
    on a low pressure condition.
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    Auto-Dual — The control mode that automatically unloads a
    modulating compressor when the bypass valve position
    reaches a specified value or the check valve closes. Once
    unloaded, this control mode will automatically reload the
    compressor when the system pressure drops below a
    specified value.
    Auto-Dual Unload Timer  The time delay, in seconds, at
    which the machine will be unloaded after the bypass valve
    has passed and stayed below the unload point when
    Autodual is active.
    Auto-Hot Start — A control mode that automatically starts
    and loads the compressor on a low-pressure condition.
    Auto-Reload — The portion of Auto-Dual control mode that
    automatically reloads the compressor when the pressure
    drops below a specified value.
    Auto-Start Pressure  The system pressure, in pressure
    setpoint units, at which the machine will start when either
    auto hot or cold start is active.
    Axial Position — The position of the rotating assembly with
    respect to the horizontal axis of the pinion.
    Baud Rate — Unit of signaling speed for data
    communications. The speed in baud is the number of line
    changes (in frequency, amplitude, etc.) or events per
    second. At low speeds each event represents only one bit
    and baud rate equals bits per second. As speed increases,
    each event represents more than one bit, and baud rate
    does not truly equal bits per second.
    BCM — Base Control Module. The device of the CMC that
    receives all of the compressor inputs and outputs and makes
    decisions about how the compressor is to operate.
    Binary Signal — The type of signal used in
    communications. Binary refers to the smallest size of data
    being transmitted, a bit.
    Blow-off Valve — Also know as a bypass valve or antisurge valve. This valve protects the compressor from surge
    by bypassing a percentage of the compressed air to the
    atmosphere, which results in keeping the compressor loaded
    above the surge point.
    BPS — Bits per second. Unit of signaling speed for data
    communications.
    Bridge — A device which forwards traffic between network
    segments based on data link layer information. These
    segments would have a common network layer address.
    Bypass Valve — See blow-off valve.
    CAT 5 — Category 5. A classification of cable used in
    twisted-pair networks.
    CE Mark — The CE Mark is a combination of various
    individual European standards into one set of standards for
    the entire European community. The Mark is a self
    declaration and self marking process. Once you have proven
    that the particular equipment meets the requirements of CE
    1
    2
    Mark and have the data to back it up, you may mark the
    product with the CE Mark.
    Citect — One of many SCADA software packages that can be
    used for air system integration.
    Choke — Also know as stonewall. This is the maximum flow
    that can be compressed by a given machine’s hardware
    configuration.
    Circuit Breaker — An automatic switch that stops the flow of
    electric current in a suddenly overloaded or abnormally
    stressed electric circuit.
    CMC — Centac MicroController.
    CMC System — Any combination of CMC control components
    which when combined create a control system. The typical
    CMC system consists of a Base Control Module (BCM),
    Operator User Interface (OUI), and Power Supply (PS). A
    common variation on the typical system is the addition of a
    Universal Communications Module (UCM).
    Coast Timer — The time interval, in seconds, between a
    compressor stop or trip and the motor coming to a complete
    stop. The timer is used to inhibit restarting.
    Compressor Load, Load — The power consumption of the
    compressor. It is typically indicated in amps, kilowatts, SCFM,
    etc.
    COM Port — See Serial Port.
    Control Transformer — The transformer that is used to
    reduce the incoming voltage (for the prelube pump motor and
    oil heater) to approximately 120 volts for controlling the CMC
    electrical devices (relays, power supply, etc.).
    Control Valve — The inlet or bypass valve used to control
    pressure or current.
    Control Variable, Process Variable — The variable being
    regulated. When at MinLoad the control variable is load for the
    inlet valve and System Pressure for the bypass valve. When at
    MaxLoad the control variable is load and when loaded the
    control variable is System Pressure.
    CSA Approval — Canadian Standards Association approval is
    required for all electrical devices shipped into Canada. This
    association is similar to UL for the United States and CE for
    Europe.
    CT — Current Transformer.
    CT Input Channel — The current transformer input channel.
    CT Ratio — Current Transformer Ratio. The current
    transformer ratio used in displaying the motor current; e.g.
    600:5 = 120.
    Current Transformer — The electrical device used to
    measure the amps of the main drive motor. For our standard
    application, we only measure the current from one of the three
    phases.
    Daisy Chain — A method of wiring a communication network.
    This method starts with the “master” and it is wired directly to
    compressor #1. Compressor #2 is wired to compressor #1,
    then compressor #3 is wired to compressor #2.
    CMC TECHNICAL REFERENCE MANUAL
    Data Link — A direct serial data communications path
    between two devices without intermediate switching nodes.
    Data Highway Plus — A communication protocol used by
    Allen-Bradley PLC 5 and SLC500 PLCs.
    DCS — See Distributed Control System.
    degC — Degrees Celsius, Centigrade.
    degF — Degrees Fahrenheit.
    DH+ — See Data Highway Plus.
    Derivative Mode — Provides a change in the control
    variable (through the inlet or bypass valve) based on the rate
    of change of the error (setpoint pressure minus system
    pressure).
    Derivative Constant — Also know as the rate time, in units
    of seconds.
    Design Point — The pressure and capacity required at
    maximum ambient conditions.
    Digital Device — A device, which is either on or off; e.g., the
    N.C. contact on the seal air switch.
    Discrete Device — See Digital Device.
    Discharge Pressure — The gas pressure between the last
    stage of compression and the check valve.
    Distributed Control System — A system that attempts to
    control an entire plant or process with multiple independent
    local controllers by networking these local controllers to a
    central computer through digital communications. These
    central computers can be a PC, PLCs or other larger
    systems. Some manufacturers of these DCS products are
    Bailey, Honeywell, Allen-Bradley, Siemens, and others.
    Drain Wire — An insulated wire in contact with a shield
    throughout its length, and used for terminating the shield.
    Dry Contacts — A set of contacts that require a power
    source supplied by others (customer). This is the normal
    type of contacts that we provide.
    Electro-pneumatic — A term used to indicate a combination
    of electronics and pneumatics. In the past, we provided
    electro-pneumatic panels as standard equipment. With the
    advent of digital computers, most all control panels are
    electronic.
    ERAM — Erasable Random Access Memory.
    Event — The control transfer or “rule(s)” as used in State
    Logic to transfer from one state to another.
    FactoryLink — One of many SCADA software packages
    that can be used for air system integration.
    FLA — Motor Full Load Amps. The motor amperage at full
    load, this value is found on the motor nameplate.
    Flexible Conduit — Small diameter hose, made of plastic
    coated aluminum, which is used to enclose wire from the
    control panel to machine mounted instruments.
    Fused Disconnect — As a safety precaution, this option
    removes power from the panel before the door is opened. By
    turning the rotary door handle, the panel power is
    terminated. The disconnect would have to be mounted
    22204796 Rev. B, Version 3.10
     1996-2003 Ingersoll-Rand Company
    Date of Issue: March 24, 2003
    CMC TECHNICAL REFERENCE MANUAL
    external to the panel enclosure. The short circuit capacity,
    maximum ground fault, motor full load amps, motor locked rotor
    amps and motor voltage must be known to size the disconnect
    properly.
    Ground — A connection to earth or to some extended
    conducting body that serves instead of the earth.
    Ground Loop — An unwanted, continuous ground current
    flowing back and forth between two devices that are at different
    ground potentials.
    Grounded System — An electrical system in which at least
    one point (usually a wire) is intentionally grounded.
    Head — See Polytropic Head.
    High Load Limit — See HLL
    HLL — High Load Limit. The load that the controller maintains
    when at MaxLoad.
    I/O — See Input/Output.
    IBV — Inlet Butterfly Valve. See Inlet Valve.
    IEC — International ElectroTechnical Commission is the
    governing body of Europe for electrical equipment and codes.
    IGV — Inlet Guide Vanes. See Inlet Valve.
    Inlet Unload Position — The position of the inlet valve when in
    the unloaded state.
    Inlet Valve — The device used on the inlet pipe to the
    compressor that restricts the amount of airflow to the
    compressor. This valve can be a butterfly valve or a valve with
    inlet guide vanes.
    Input/Output —The hardware interface between the
    compressor and the control system. This term generically
    applies to the entire interface circuit including sensor, wiring,
    and junction points.
    Instrument Air — The air supply to the panel that is directed to
    the power air system for the inlet and bypass valves and the
    compressor seals.
    Integral Mode — Provides a change in the control variable
    (through the inlet or bypass valve) based on the time history of
    the error (setpoint pressure minus system pressure).
    Integral Time Constant—This value is expressed in repeats
    per second and represents the number of times per second the
    integral mode acts.
    Intellution — One of many SCADA software packages that
    can be used for air system integration.
    Interface — The hardware or software device used to
    communicate between products.
    Interlock — An electrical function that prevents the
    compressor from starting in the event that the function has not
    been satisfied. For example, the seal air interlock prevents the
    compressor from starting until the seal air pressure is
    adequate.
    IRBUS — The proprietary communication protocol used to
    communicate to and from one or many Base Control Modules
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    (BCM), Universal Communication Modules (UCM) and
    Operator User Interfaces (OUI).
    Loopback — A diagnostic test in which a transmitted
    communication signal is returned to the sending device after
    passing through all or part of the communication network.
    This test compares the transmitted signal to the received
    signal. The test passes if the signals are identical.
    MA, mA — Milliampere
    Maintained Contact — A contact closure that remains
    closed.
    MaxLoad — The message displayed on the OUI Status Bar
    when the machine is running at MaxLoad.
    MinLoad — The message displayed on the OUI Status Bar
    when the machine is running at MinLoad.
    MMI — Man Machine Interface. The term used to indicate
    the device or method used for a human to interface with a
    machine. Typically these interfaces are LCD displays or
    computer screens. For the CMC, the MMI is the Operator
    User Interface (OUI).
    Modbus — A sixteen-bit communication protocol originally
    developed for Modicon PLCs. This protocol has become a
    defacto standard for industrial equipment.
    Modicon — A PLC brand name manufactured by Schneider
    Automation.
    Modulate — The control mode that opens and closes
    (modulates) the inlet or bypass valve to maintain a constant
    discharge pressure. This is the primary control mode for
    centrifugal compressors.
    Momentary Contact — A contact closure that closes and
    then opens.
    N.C. — Normally Closed. Used to indicate the state of a
    contact when no power is applied.
    N.O. — Normally Open. Used to indicate the state of a
    contact when no power is applied.
    Natural Curve — The set of pressure and capacity points
    that define the operating characteristic of the centrifugal
    compressor.
    Natural Surge — The point on the natural curve that is
    represented by the maximum pressure and minimum
    capacity.
    NEMA — National Electrical Manufacturers Association.
    Network — A series of points, nodes or devices connected
    by some type of communication medium.
    On-Line/Off-Line — Control mode that allows the system
    discharge pressure to fluctuate between two pressure
    setpoints. The compressor will load when the actual
    pressure is below the lower setpoint pressure and will unload
    when it reaches the higher setpoint pressure. This type of
    control mode is normally used on reciprocating and rotary
    compressors.
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    OUI — Operator User Interface. The device on the CMC that
    gathers user inputs and provides compressor operating status.
    Parity — The addition of non-information bits to make up a
    data transmission block that ensures the total number of 1s is
    either even (even parity) or odd (odd parity). This is used to
    detect errors in communication transmission.
    Partial Unload — See Surge Absorber.
    Password — The four digit parameter used to determine when
    the user can modify setpoints. The range of this password is
    0000 to 9999.
    PID — Proportional, Integral, Derivative. The parameters used
    to adjust the behavior of PID control loops.
    PLC — Programmable Logic Controller. This hardware device
    is configurable such that many types of analog and digital
    inputs and outputs can be utilized to control various industrial
    products.
    PLC 5 — Type of Allen-Bradley PLC used for large
    applications.
    Pneumatic — Run by or using compressed air.
    Polytropic Head — The energy in foot-pounds to transfer one
    pound of given gas from one pressure level to another. (ft-lb/lb)
    Positioner — The device on a control valve that instructs the
    actuator how much (to what position) to move the valve.
    PROM — Programmable Read Only Memory.
    Proportional Mode — Provides a change in the control
    variable (through the inlet or bypass valve) proportional to the
    error (setpoint pressure minus system pressure).
    Proportional Band Constant — The percent change in
    system air pressure that causes a percent change in the valve
    position. This value is dimensionless.
    Protocol — A formal set of conventions governing the
    formatting and relative timing of message exchange between
    two communication systems.
    RAM — Random Access Memory.
    Relative Address — For Modbus compliant devices, the fourdigit address within the range of 0-9999. The relative address
    can be determined from the absolute address by deleting the
    type (the ten-thousandth place) and subtracting one.
    Reload Percent — The reload pressure, in percent of user
    pressure set point, at which the machine will load when
    Autodual is active.
    Rigid Conduit — Small diameter pipe, made of carbon steel
    with welded connections, which is used to enclose wire from
    the control panel to machine mounted instruments. This conduit
    is typically used in hazardous area classifications.
    Rise To Surge — The amount of pressure from the operating
    pressure to the natural surge pressure. This amount is usually
    expressed in percent.
    RS-232 — Electronic Industries Association interface standard
    between data terminal equipment and data communication
    equipment, using serial binary data interchange. This is the
    most common standard used by industry.
    RS-232 to RS-422/485 Converter — A hardware device that
    electrically converts an RS-232 signal into an RS-422 or RS485 signal.
    RS-422 — Electronic Industries Association interface
    standard that specifies electrical characteristics for balanced
    circuits and extends transmission speed and distances
    beyond RS-232. This standard is a balanced voltage system
    with a high level of noise immunity.
    RS-485 — Electronic Industries Association balanced
    interface standard similar to RS-422, but uses a tri-state
    driver for multi-drop applications.
    RTD — Resistance Temperature Detector. An instrument
    that measures temperature by detecting the voltage across
    the RTD material (mostly platinum). The temperature is
    determined because as the temperature increases the
    resistance increases.
    RTU — Remote Terminal Unit. A device typically used for
    data acquisition to gather data. By using this definition, the
    Base Control Module is an RTU.
    SCADA — Supervisor Control and Data Acquisition. The
    generic classification for software that gathers data for
    control of industrial products.
    Sequencer — A hardware or software device that controls
    the order in which compressors starts, stops, loads and
    unloads. Some sequencers also control loading and
    unloading through incremental pressure setpoints among the
    compressors. For example, in a three-compressor
    application the setpoints may be 101 psi for compressor #1,
    100 psi for compressor #2 and 99 psi for compressor #3.
    Assuming the pressure transducers were calibrated within
    one psi of each other and the machines were running
    unloaded, this configuration would drive compressor #1 to
    load first when the pressure dropped to 101 psi.
    Serial Device — A Personal Computer (PC), Programmable
    Logic Controller (PLC), Distributed Control System (DCS) or
    any other device that can transmit, receive and interpret an
    RS422/485 formatted signal.
    Serial Port — The RS-232 connection on the back of a PC
    to communicate with other equipment. This connection is
    typically referred to as COM1. A single PC can have more
    than one serial port.
    Service Tool — The software used on the PC to configure,
    tune, record and log data from the CMC.
    Service Tool Plug — A port on Panel door to provide
    access to IRBUS Network. Requires Laptop and external
    UCM.
    Setpoint Ramp Rate — The gradual increase of the system
    pressure set point during a loading operation of the
    compressor. The ramping of the system pressure set point
    helps to smooth the transition and prevents a pressure
    overshoot in the air system upon initial compressor loading.
    Shielded Wire — Wire that has a sheet, screen or braid of
    metal, usually copper, aluminum, or other conducting
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    CMC TECHNICAL REFERENCE MANUAL
    material placed around or between electric circuits or cables or
    their components, to contain any unwanted radiation, or to
    keep out any unwanted interference.
    SLC500 — Type of Allen-Bradley PLC used for relatively small
    applications and is lower in cost than an equivalent PLC 5.
    Start Timer — The time interval, in seconds, between pressing
    the Start button and the compressor is running at full speed.
    The timer is used to transition wye delta starters, inhibit
    loading, de-energize the prelube pump, and disable the
    alternate alarm and trip setpoints.
    State — A task that is currently being executed in State Logic.
    Only one state is active at one time.
    State Logic — State Logic is an alternative to traditional
    control languages used for machines, systems, and processes.
    State Transition — The movement from one state to another
    based on one or more events.
    Status Bar — The Status Bar provides four distinct types of
    information (Compressor Operating State, Compressor Status,
    Compressor Control Location and Page Number). This region
    is always visible from any folder and page combination.
    Stonewall — See Choke.
    Surge Absorber — The reaction of the control system to a
    surge that pops the bypass valve open by a small percentage
    to get the compressor out of the surge condition. This feature is
    initiated by surge detection.
    Surge Anticipation — The ability of a control system to
    prevent surge by predicting that a surge is about to happen.
    Surge Detection — The ability of a control system to indicate
    that a surge has happened. This feature is important because a
    persistent surge condition can damage the compressor. Once
    detected, the control system can respond to the event by taking
    a corrective action; i.e., by opening the bypass valve.
    Surge Indexing — A method of automatically increasing the
    setting of TL upon a surge.
    Surge Indexing TL — The setpoint at which the inlet valve
    controls to MinLoad.
    Surge Line — A series of points that represent natural surge
    for various inlet pressure conditions.
    Surge PTX — Surge Pressure Transducer. Surge PTX is
    mounted between the last compression stage and the check
    valve.
    Surge Sensitivity — A setpoint that is used to indicate the
    magnitude of pressure and current changes that occur during a
    surge condition. This setpoint determines when the control
    system detects a surge.
    Surge Unload — The reaction of the control system to a surge
    that unloads the compressor to exit the surge condition. This
    feature is initiated by surge detection.
    Switch, Ethernet — A device connected to several other
    devices. Transfers messages across the network.
    System Pressure — The pressure at the location of the
    system pressure transducer.
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    Terminal Block — A device that is used to connect to wires.
    Typically, these blocks are provided for customer field wiring
    to the panel and when one wire is to be connected to
    multiple devices.
    Terminating Resistor — A resistor placed at the end of a
    communication network for absorbing or sufficiently
    attenuating signals incident on it so that they are not
    reflected back into the transmission line at amplitudes where
    they would cause distortion of the data signal. Typically, a
    resistor is placed at each end of the network to help
    eliminate noise.
    Thermocouple — A device used to measure temperatures
    accurately and consists of two dissimilar metals joined so
    that a voltage is generated between to the contacts of the
    two metals as the temperature changes.
    Throttle Limit — See TL.
    Throttled Surge — The condition created by closing the
    inlet valve past the surge point to maintain constant
    pressure.
    Tight Closure — A term used to describe the inlet valve
    position when the compressor is not running and starting.
    The inlet valve ideally is closed tightly when stopped to
    prevent reverse rotation of the compressor if the check valve
    fails. Also, to reduce the load on the compressor during
    starting, the inlet valve can be held closed for a short period
    of time (less than thirty seconds) after the start button is
    pushed. This is most typically done on compressors at high
    altitude, most notably snow making applications. Bearing
    analysis must be done prior to using this option.
    TL — Throttle Limit. Establishes the minimum flow through
    the machine when loaded, it is the maximum point of inlet
    valve throttling. If system demand is below this throttle point,
    the compressor must bypass air to maintain pressure
    setpoint or unload.
    TL increment value — When Surge Indexing is enabled, the
    TL increment value is the amount added to the Surge
    Indexing TL upon a surge. The Surge Indexing TL will stop
    being incremented when and if the value reaches MaxLoad.
    Transducer — An electrical device that provides a usable
    output (4-20 mA, 0-5 vDC, etc.) in response to a measured
    property (pressure, temperature, etc.).
    Transformer — An electrical device that transfers energy
    from one circuit to another by electromagnetic induction.
    Transient Voltage Surge Suppressor — An electrical
    device that prevents temporary over-voltages of short
    duration (typically associated with lightning strikes and
    ground faults on an ungrounded system) from damaging
    other electrical equipment.
    Transmitter — An electrical device that sends the digital
    representation of a real measured value (e.g., pressure,
    temperature), to the BCM in the control panel for analysis
    and display.
    Turndown — The amount of capacity that can be decreased
    from full load (maximum load) at a constant pressure before
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    CMC TECHNICAL REFERENCE MANUAL
    the bypass valve begins to open to avoid surge. This amount is
    usually expressed as a percent of full load capacity.
    TVSS — See Transient Voltage Surge Suppressor.
    Twisted Pair Wire — Paired cables allow balanced signal
    transmission, which results in signals with low noise. Due to the
    improved noise immunity of twisted pairs, data speeds are
    usually higher than those of multi-conductor cables.
    UCM — Universal Communications Module. The device that
    allows outside systems to communicate with the CMC.
    UL — Underwriter’s Laboratory.
    Ungrounded System — An electrical system, without an
    intentional connection to ground.
    Unload — The operating mode that passes a small amount of
    air through the compressor and bypasses it to the atmosphere.
    In this mode, the inlet valve is cracked open a small amount
    and the bypass valve is fully open. This mode is used when
    starting the compressor before loading, stopping the
    compressor and during periods of no demand.
    Unload Point — The bypass valve position, in percent open, at
    which the Autodual unload timer will start timing to unload the
    compressor when Autodual is active.
    User Pressure Set Point — The local control pressure set
    point.
    Valve Stroking — The process of calibrating the valves to
    align the fully open position to 100 percent and the fully closed
    position to 0 percent of output signal.
    VDC — Volts Direct Current
    Voltage Regulator — An electrical device that maintains
    voltage to a predefined level.
    Wait Timer — The delay interval, in seconds, between power
    up and the ready state.
    Wire Gage — See American Wire Gage.
    Wonderware — One of many SCADA software packages that
    can be used for air system integration.
    Z-Purge — Required when the customer environment is
    Division 2. A Type Z Purge reduces the classification within an
    enclosure from Division 2 too non-hazardous. When provided,
    a NEMA 4 or NEMA 4X enclosure is required. Hand valve
    selectable quick and slow purges, with flow meters are
    provided to regulate the amount of gas entering the panel. A
    differential pressure switch is wired to a light on the front of the
    panel to indicate if there is a loss of purge gas. A relief valve is
    installed to prevent over-pressurization and a warning label,
    text below, is affixed to the front of the panel.
    22204796 Rev. B, Version 3.10
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    Date of Issue: March 24, 2003