Patent Publication Number: US-8972064-B2

Title: Actuator with diagnostics

Description:
This is a continuation of patent application Ser. No. 13/293,051, filed Nov. 9, 2011. Patent application Ser. No. 13/293,051, filed Nov. 9, 2011, is hereby incorporated by reference. 
    
    
     BACKGROUND 
     The present disclosure pertains to control devices and particularly to mechanical movers of devices. More particularly, the disclosure pertains of actuators. 
     SUMMARY 
     The disclosure reveals a system incorporating an actuator. The actuator may have a motor unit with motor controller connected to it. A processor may be connected to the motor controller. A coupling for a shaft connection may be attached to an output of the motor unit. The processor may incorporate a diagnostics program. The processor may be connected to a polarity-insensitive two-wire communications bus. Diagnostic results of the diagnostics program may be communicated from the processor over the communications bus to a system controller. If the diagnostic results communicated from the processor over the communications bus to the system controller indicate an insufficiency of the actuator, then an alarm identifying the insufficiency may be communicated over the communications bus to the system controller. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is a diagram of an example layout of actuators and a controller connected to a common bus; 
         FIG. 2  is a diagram of actuators connected to a controller via a bus and to a roof top unit; 
         FIG. 3  is a diagram of an auxiliary switch setpoint control approach; 
         FIG. 4  is a diagram of an actuator, an economizer and sensor connected to one another via a bus; 
         FIG. 5  is a diagram of front and back sides of an actuator revealing certain knobs for control and adjustment such as an address selector being accessible from both sides; 
         FIG. 6  is a diagram that shows perspective views of two sides of an actuator revealing the reversibility of actuator position for access to a selector from two sides of the actuator; 
         FIG. 7  is a diagram of a close view of a selector or mode switch showing positions available for a test mode and addresses of an actuator; 
         FIG. 8  is a diagram of a two-wire polarity-insensitive bus controlled actuator; 
         FIG. 9  is diagram of another layout of another actuator; 
         FIGS. 10   a  through  10   r  are schematics of circuitry for the actuator as represented by  FIG. 9 . 
     
    
    
     DESCRIPTION 
     Coupled actuators may be used within heating, ventilating and air-conditioning (HVAC) systems. They may drive final control elements. Example applications may incorporate volume control dampers, mounted directly to the drive shaft of the actuator or remotely with the use of accessory hardware, rotary valves such as ball or butterfly valves mounted directly to the actuator drive shaft, and linear stroke or cage valves mounted with linkages to provide linear actuation. The actuator may also be used to operate ventilation flaps, louvers and other devices. The actuator may be a spring return device designed for clockwise or counterclockwise fail-safe operation with a continuously engaged mechanical spring. The spring may return the actuator or the mechanism that the actuator is operating to a fail-safe position within a certain time of power loss. An example of the certain time may be 25 seconds. The actuator may be mounted to provide clockwise or counterclockwise spring return by flipping or turning the unit over. The stroke of the actuator may be adjusted for an application at hand. An auxiliary knob may be used to control minimum position or switch position. For switch position, a degree of rotation may be selected for where the switch is desired to activate. The actuator may have an override of the control signal for certain applications such as for example freeze protection. The override may move the actuator to a full open or full closed position. One instance of position change is that the actuator may be designed to respond to direct digital control (DDC) instantaneous contact closures. 
       FIG. 1  is a diagram of an example layout of actuators  41 ,  42 ,  43 ,  44  and  45  connected to a common bus  46 . Bus  46  may be connected to a controller  47 . Controller  47  may be Spyder controller. Bus  46  may be a Sylk bus. The actuators may be Zelix actuators. Each actuator may have its open and close speeds individually set by controller  47  via signals on bus  46 . For examples of various settings, actuator  41  may have a speed set to a 90 second timing, actuator  42  a speed set to a 30 second timing; actuator  43  a speed set to a 30 second timing for opening and a 90 second timing for closing, actuator  44  a speed set to a 60 second timing for a normal mode and a 30 second timing for an emergency mode, and actuator  45  a speed set for a 180 second timing. The speeds each of the actuators may be set to different timings. When a speed of an individual actuator is set by controller  47 , the respective actuator may be selected according to its address. Fir instance, actuators  41 ,  42 ,  43 ,  44  and  45  may have addresses  11 ,  12 ,  13 ,  14  and  15 , respectively. 
       FIG. 2  is a diagram of actuators  41  and  42  connected to controller  47  via bus  46 . Actuators  41  and  42  may have connections to a roof top unit (RTU)  48 . Actuator  41  may have a variable frequency drive control output of 2 to 10 volts along lines  51  to a component  53  at RTU  48 . Actuator  42  may have an auxiliary output binary 24 volts along lines to a component  54  of RTU  48 . 
     A present actuator with an auxiliary output may be adjustable via network communications. Auxiliary (aux) switches on actuators in some of the related art may have their setpoints established locally on the actuator. Setting an auxiliary switch setpoint may be rather difficult because of an actuator location (e.g., in a ceiling or behind equipment) and in general auxiliary switch setpoint user interfaces may be difficult to set and see (e.g., cam systems, rotating assemblies and adjustable detents) which could lead to setpoint inaccuracies. Also, there may be a fixed hysteresis with each of these solutions. 
     An additional problem with some of the solutions in the related art is that they are not necessarily adjustable as a relevant application changes. For example, an aux switch may be set to make or break at around 45 degrees of the actuator&#39;s stroke. If set for 45 degrees, the aux switch may virtually always trip at that position and can not necessarily be changed without a service technician physically changing the setpoint. Some applications would benefit by having the aux switch make at 20 degrees while opening, and break at 60 degrees while closing, or 20 degrees during a heat mode and 45 degrees during a cool mode, or vice versa. 
     Also, some of the aux switches of the related art may only be able to change state based on an actuator shaft position. There may be many applications where switching the aux switch based on temperature or some other variable (or combination of variables) would be beneficial. 
     The present approach may solve the issues by allowing the auxiliary switch setpoint and control parameters to be configured remotely over the bus in real time. This approach may be implemented with digital or analog outputs and there could be a multiple setpoint per relay solution. 
     The present approach may be effected by enhancing the software in the controller and communicating actuator systems. It may be used by allowing the auxiliary switch parameters to be programmable via a higher order controller. An example may incorporate using a Jade controller or Spyder™ controller with Niagara™ (or Fishsim™) to program the functionality of a Sylk™ Zelix™ communicating actuator over a Sylk bus. A Sylk bus may be a two-wire, polarity insensitive bus that may provide communications between a Sylk-enabled actuator and a Sylk-enabled controller. An example of the Sylk bus circuitry may be disclosed in U.S. Pat. No. 7,966,438, issued Jun. 21, 2011, and entitled “Two-wire Communications Bus System”. U.S. Pat. No. 7,966,438, issued Jun. 21, 2011, is hereby incorporated by reference. 
       FIG. 3  is a diagram of an auxiliary switch control approach. Symbol  11  may indicate an auxiliary position change which may be initiated. An auxiliary switch setpoint may be controlled manually by an auxiliary potentiometer in symbol  12 . Symbol  13  indicates that if the current actuator position is greater than the setpoint set by the auxiliary potentiometer, then the auxiliary switch may be activated. If not, then the auxiliary switch may be deactivated. Alternatively, in symbol  14 , the auxiliary switch setpoint may be controlled by an external controller command. Symbol  15  indicates that if the current actuator position is greater than the setpoint set by an external controller command, then the auxiliary switch may be activated. If not, then the auxiliary switch may be deactivated. 
     A present communicating actuator may have a network adjustable running time. Applications in the field may require or benefit from different running time actuators. In the related art, different running time actuators might be purchased by model number, or programmable actuators may be programmed at commissioning using an independent tool. This situation may dictate that a person pick one running time for the actuator and application at the beginning of an implementation of the actuator. 
     An example of an issue of running time may occur during system checkout in an OEM factory or in the field. An OEM or field technician may prefer a fast running time (10 seconds) so that the actuator system can be checked out quickly without having to wait for a 90 second actuator to run its time. 
     The present approach may incorporate an actuator that allows programmable running time via the local bus. Over the bus, the actuator&#39;s running time may be programmed to different values at different times during the actuator&#39;s lifecycle. For example, the actuator may be programmed for 15 second timing during a test, 30 second timing during a normal application mode, and 90 second timing during a saver mode. 
     The present actuator approach may be applied in a Jade™ economizer/Sylk Zelix system implementation. The Sylk bus hardware may be implemented on the controller and the actuator. Then the firmware in these products may be created to implement the adjustable running time functionality. 
       FIG. 4  is a diagram of a Zelix actuator  21  with Jade economizer  22  connected to the actuator via a Sylk bus  23 . A sensor  24  may be connected into the Sylk bus. 
     A present approach may incorporate a potentiometer address selection for an actuator. Setting a network address on a communicating actuator may be rather difficult. The actuator may be typically located in a hard to reach area (e.g., in a ceiling or behind equipment). Related art approaches may involve actuators that are typically small and hard to see and actuate (e.g., with dip switches/rotary encoders) and may use binary techniques as described herein which may require multiple microcontroller input pins. 
     The present approach may solve the issue by using a potentiometer to set and establish a network address on a communication actuator. The approach may allow for an address selector to be accessible from both sides of the actuator using a single potentiometer, the numbers and interface to be large and easy to read, and it may allow the address to be selected using only one analog input on the microcontroller. 
       FIG. 5  is a diagram of a front view  31  of an actuator  33  and a back view  32  of the actuator. Certain knobs for control and adjustment such as an address selector  34  may be accessible from both sides of actuator  33 . Selector  34  may have five positions for address selection. For instance, a position 1 may be for selecting an address  11 , position 2 for address  12 , position 3 for address  13 , position 4 for address  14  and position 5 for address  15 . A position 6 may be for selecting a test mode. 
       FIG. 6  is a diagram that shows perspective views of sides  31  and  32  of actuator  33  revealing the reversibility of the actuator for access to selector  34  from both sides of actuator  33 . 
     The present approach may incorporate an actuator which has accessible onboard diagnostics. An issue in the related art may be that actuators in the field can fail or malfunction and of which many cases may be undetected. Such actuators may be wasting energy or giving up comfort for years before the failure is found. 
     The present approach may solve this issue by communicating alarms, status and diagnostics automatically over a bus. If an actuator fails, an alarm may be sent to the higher order controller for immediate notification. These software alarms and diagnostic features may be implemented in the firmware for a Sylk Zelix communicating actuator. 
     A controller or processor may provide on the communications bus one or more diagnostics items of a group consisting of high temperature warning, excessive noise on power line, record/report back electromotive force (EMF) on spring return, percentage of life detection, high amount of travel for given amount of time, hunting around a given point, actuator angle, communication normal indicator, stroke limiting, control valve (Cv) selection, flowrate on pressure independent control valve (PIC-V), set auxiliary switch, report auxiliary switch setting, report auxiliary switch status, report auxiliary switch current draw—auxiliary equipment status, if switch drives fan—verify fan shuts down before damper closes, if switch drives coils—verify heat exchanger running before opening/closing valve, report stuck valve/damper, PIC-V constant pressure—constant torque, changeover valve—no cycling for a period of time, time since last movement, date/time of first operation (commissioning), audible/detectable signal for location, device in warranty, device model number/serial number/date code, device type—outside air damper/standard ball valve/PIC-V valve/mixed air damper, actuator fitness/self-test routine—known system conditions, sensor—actual damper/valve position, super capacitor status, and energy consumption. 
     The present approach may incorporate an actuator test mode. There may be several approaches used by an actuator installer to verify that an actuator has been installed correctly. One approach may involve an operator at the control panel to cause the actuator to open and close. In another approach, the installer or maintainer may have access the connector and short the modulating input to cause the actuator to open, thus verifying that the actuator is working and connected properly. 
     With the test mode, there may be a test mode selection on a pot or switch that causes the actuator to move to its open position. An installer or maintainer may then just select Test Mode via the pot and verify an operation of the actuator without needing to access the connector or to communicate with a control operator. 
     Actuator software may verify that the test mode has been selected on the switch or potentiometer. The software may then exercise the following algorithm. 
     IF Test Mode THEN 
     Set actuator speed to maximum allowable speed 
     Cause actuator to open (move to end of its allowable span) 
     Remain in this position while in Test Mode. 
       FIG. 7  is a diagram of a closer view of the selector or mode switch  34 , showing 6 positions available for the test mode of actuator  33 . A mode plate  35  indicates that position 6 may be designated for “Test” or test mode. Positions 1-5 indicate five different addresses available for selection by switch  34 . 
       FIG. 8  is a diagram of a two-wire polarity-insensitive bus (i.e., Sylk) controlled actuator  61 . An electric motor  62  may drive a gear train  63  which turn an actuator shaft  64  which may move a damper, valve, or other component. A processor  65  may be connected to motor  62  and provide control of the motor. Processor  65  may also be connected to a communications bus  66 . A shaft position potentiometer  67  may be mechanically connected to the actuator shaft  64  or a part on the gear train to electrically provide a position of shaft  64  to processor  65 . An auxiliary switch output  68  and an analog output  69  may be provided by processor  65 . A user interface  71  may provide a bus address select to processor  65 . A user interface  72  may provide a manual auxiliary switch trigger select. Actuator  61  may be connected to other devices  73  such as actuators, sensors, controllers, and so on. Actuator  61  may have a power supply  74  to power its components. An AC power line  75  or other source may provide power to supply  74 . 
       FIG. 9  is a diagram of an actuator  120 . Many components of actuator  120  are revealed in the diagrams shown in  FIGS. 10   a  through  10   r . Interconnections of the components may be indicated in the diagrams as identified by various connections and wires having labels and alphanumeric symbols. For example, a line identified as A 1  in  FIG. 10   a  may be connected to a line identified as A 1  in  FIG. 10   b . A processor  101  may be connected to power supply electronics  105 , bus electronics and isolation transformer  109 , a motor control  103  and a shaft position indicator  102 . Processor  101  may also be connected to an auxiliary switch  108 , an auxiliary switch and position potentiometer  110 , and a user address and auxiliary switch selector  107 . Further, processor  101  may be connected to an analog out  106  and functional test electronics  104 . 
     A motor  112  may be connected to motor control  103 . An output of motor  112  may be mechanically connected to a gear reduction train  113 . Gear train  113  may have an actuator coupling or shaft  114  for connection to a mechanically controlled or operated device  115  such as, for example, a damper, valve, flap, louver, and so on. Gear train  113  may be connected to shaft position indicator  102 . 
     Bus electronics and isolation transformer  109  may be connected to a communications bus  116 . Outside actuator  120 , bus  116  may be connected to controllers  117 , sensors  118 , actuators  119 , and other devices  121  and various communication media  122 . An outside power source  123  may be connected to power supply electronics. 
     Processor  101  may be shown in a diagram of  FIG. 10   a . Shaft position indicator  102  may be shown in a diagram of  FIG. 10   b . Motor control  103  may be shown in diagrams of  FIGS. 10   c ,  10   d  and  10   e . Functional test electronics may be shown in a diagram of  FIG. 10   f . Power supply electronics may be shown in diagrams of  FIGS. 10   g  and  10   h . Analog out electronics  106  may be shown in diagrams of  FIGS. 10   i  and  10   j . User address and auxiliary switch circuitry  107  may be shown in diagrams of  FIG. 10   k . Auxiliary switch circuitry  108  may be shown in a diagram of  FIG. 10   l . Communications bus electronics  109  may be shown in diagrams of  FIGS. 10   m ,  10   n ,  10   o  and  10   p . Auxiliary switch and position potentiometer circuitry  110  may be shown in a diagram of  FIG. 10   q . Miscellaneous circuitry  125 , such as thermistor, oscillator and flash electronics may be in diagrams of  FIG. 10   r . Some of the other Figures noted herein may show diagrams of other portions of circuitry helpful in building the actuator system. 
     The following is a recap of the present actuator system. An actuator system for use with heating, ventilating and air conditioning (HVAC) equipment, may incorporate an HVAC actuator. The actuator may have a motor, a motor controller connected to the motor, a processor connected to the motor controller, and a coupling for a shaft connection attached to an output of the motor. 
     The processor may incorporate a diagnostics program, and be connected to a communications bus. Diagnostic results of the diagnostics program may be communicated from the processor over the communications bus to a system controller. If the diagnostic results communicated from the processor over the communications bus to the system controller indicate an insufficiency of the actuator, then an alarm identifying the insufficiency may be communicated over the communications bus to the system controller. The communications bus may consist of two polarity-insensitive wires. 
     If the motor and/or the motor controller fails, then an alarm may be sent to the system controller as an immediate notification of an actuator failure. The processor may indicate a status of active or inactive of the actuator on the communications bus. If the status is indicated as inactive, then a condition of whether the actuator is operable or inoperable may be determined. The system controller may identify an actuator as communicating diagnostic results according to an address of the actuator. The system controller may be an economizer. 
     An actuator system for use with heating, ventilating and air conditioning equipment, may incorporate an HVAC actuator. The actuator may incorporate a motor, a gear train mechanically connected to the motor, an actuator shaft mechanically connected to the gear train, a shaft position indicator connected to the actuator shaft, and a processor connected to the motor and the shaft position indicator. The processor may have a diagnostics program, and be connected to a communications bus. 
     The actuator may further incorporate a current sensor and a voltage sensor connected to the motor and the processor. The processor may determine immediate power consumption of the actuator from current and voltage indications from the current sensor and voltage sensor, respectively. The processor may also provide an excessive power alarm if the immediate power consumption exceeds a predetermined percentage over a given amount of measured power consumption by the motor considered to be during normal operation of the actuator, and may provide an insufficient power alarm if the immediate power consumption is less than a predetermined percentage under a given amount of measured power consumption by the motor considered to be during normal operation of the actuator. 
     If the actuator fails, the processor may send an actuator failure alarm via the communications bus as an immediate notification to a system controller. The processor may provide alarms, status and diagnostics of the actuator automatically over the communications bus. The communications bus may have two polarity-insensitive wires. 
     The processor may also provide on the communications bus one or more diagnostics items of a group consisting of high temperature warning, excessive noise on power line, record/report back electromotive force (EMF) on spring return, percentage of life detection, high amount of travel for given amount of time, hunting around a given point, actuator angle, communication normal indicator, stroke limiting, control valve (Cv) selection, flowrate on pressure independent control valve (PIC-V), set auxiliary switch, report auxiliary switch setting, report auxiliary switch status, report auxiliary switch current draw—auxiliary equipment status, if switch drives fan—verify fan shuts down before damper closes, if switch drives coils—verify heat exchanger running before opening/closing valve, report stuck valve/damper, PIC-V constant pressure—constant torque, changeover valve—no cycling for a period of time, time since last movement, date/time of first operation (commissioning), audible/detectable signal for location, device in warranty, device model number/serial number/date code, device type—outside air damper/standard ball valve/PIC-V valve/mixed air damper, actuator fitness/self-test routine—known system conditions, sensor—actual damper/valve position, super capacitor status, and energy consumption. 
     An approach for attaining diagnostics of an actuator for use in heating, ventilating and air conditioning (HVAC), may incorporate entering a diagnostics program for an HVAC actuator into a processor of the actuator, transmitting results of the diagnostics program on a communications bus, and reviewing the results from the communications bus. The diagnostics program having alarms and diagnostic characteristics may be implemented in firmware of the processor. 
     The actuator may have a motor, a gear train connected to the motor, an actuator shaft coupling connected to the gear train, a shaft position indicator connected to the actuator shaft coupling and to the processor, and one or more sensors situated at the actuator and connected to the processor. 
     The approach may further incorporate sending an alarm via the processor to a controller via the communications bus if the actuator shaft coupling fails to move upon transmitting signals to the processor commanding a movement of the motor. The communications bus may be a two-wire polarity-insensitive bus which can convey signals and power. 
     Two or more actuators and the controller may be connected to the communications bus. The controller may be an economizer. A processor may provide on the communications bus one or more actuator related items of a group consisting of high temperature warning, excessive noise on power line, record/report back electromotive force (EMF) on spring return, percentage of life detection, high amount of travel for given amount of time, hunting around a given point, actuator angle, communication normal indicator, stroke limiting, control valve (Cv) selection, flowrate on pressure independent control valve (PIC-V), set auxiliary switch, report auxiliary switch setting, report auxiliary switch status, report auxiliary switch current draw—auxiliary equipment status, if switch drives fan—verify fan shuts down before damper closes, if switch drives coils—verify heat exchanger running before opening/closing valve, report stuck valve/damper, PIC-V constant pressure—constant torque, changeover valve—no cycling for a period of time, time since last movement, date/time of first operation (commissioning), audible/detectable signal for location, device in warranty, device model number/serial number/date code, device type—outside air damper/standard ball valve/PIC-V valve/mixed air damper, actuator fitness/self-test routine—known system conditions, sensor—actual damper/valve position, super capacitor status, and energy consumption. 
     In the present specification, some of the matter may be of a hypothetical or prophetic nature although stated in another manner or tense. 
     Although the present system and/or approach has been described with respect to at least one illustrative example, many variations and modifications will become apparent to those skilled in the art upon reading the specification. It is therefore the intention that the appended claims be interpreted as broadly as possible in view of the related art to include all such variations and modification.