Abstract:
A system for monitoring operational conditions of one or more HVAC units, or other machines, with a plurality of sensors for collecting operational information data and transmitting data to a storage device and a processor for analyzing and trending the data and comparing it to a list of pre-determined set points to determine variances from the data set points and identification of one or more pre-determined events and a set of preventive maintenance alerts and/or troubleshooting instructions pertaining to the events and matching of the preventive maintenance alert and/or troubleshooting instructions to at least one of the events for display of the instructions to a user for resolving the event. The system may utilize a programmable logic array with a portable sensing unit, be capable of monitoring multiple parameters, including temperature, pressure, air flow, voltage, current, and humidity and interconnect to remote stations and SCADA systems.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application takes priority from a provisional application for patent entitled “Method and Apparatus For Monitoring and Troubleshooting of HVAC Equipment” having Ser. No. 62/061,765 filed Oct. 9, 2014 and is incorporated as if fully set forth herein. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable Description of Attached Appendix 
         [0003]    Not Applicable 
       BACKGROUND OF THE INVENTION 
       [0004]    This invention relates generally to the field of system maintenance and more specifically to a Method and Apparatus For Monitoring and Troubleshooting of HVAC Equipment. 
       BRIEF SUMMARY OF THE INVENTION 
       [0005]    The primary advantage of the invention is to provide a system for monitoring heating and cooling systems and machinery on a real time basis and provide troubleshooting guides to users based on sensed parameters. 
         [0006]    Another advantage of the invention is to provide real time data on the performance of heating, ventilation, air conditioning, and refrigeration systems. 
         [0007]    Another advantage of the invention is to provide sensors that shall be integrated into a programmable logic controller (PLC) which shall process the data and establish alarm levels and trigger points for preventive maintenance and troubleshooting activities. 
         [0008]    Another advantage of the invention is to provide a customer multiple interfaces including a local HMI and/or provide the ability to tie into a customer&#39;s DCS or SCADA system. 
         [0009]    Other objects and advantages of the present invention will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention. 
           [0011]      FIG. 1  is a block diagram showing system components according to a preferred embodiment of the invention. 
           [0012]      FIG. 2A through 2F  are a schematic diagram of wiring to an HVAC system according to a preferred embodiment of the invention. 
           [0013]      FIGS. 3A through 31  are display screens for event information according to a preferred embodiment of the invention. 
           [0014]      FIGS. 4A through 4H  are display screens for event information according to a preferred embodiment of the invention. 
           [0015]      FIGS. 5A through 5G  are display screens for event information according to a preferred embodiment of the invention. 
           [0016]      FIGS. 6A through 61  are display screens for event information according to a preferred embodiment of the invention. 
           [0017]      FIGS. 7A through 71  are display screens for event information according to a preferred embodiment of the invention. 
           [0018]      FIGS. 8A through 8G  are display screens for event information according to a preferred embodiment of the invention. 
           [0019]      FIGS. 9A through 91  are display screens for event information according to a preferred embodiment of the invention. 
           [0020]      FIGS. 10A through 10H  are display screens for event information according to a preferred embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    Detailed descriptions of the preferred embodiment are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for later filed claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner. 
         [0022]    The HVAC Monitoring system of the present invention in a preferred embodiment is a strap on system that provides real time data on the performance of heating, ventilation, air conditioning, and refrigeration systems. Additionally, the system may apply to filtration, purge, and pressurization systems. The core of the system is the instrumentation of the equipment using various sensing methods that shall include discrete (on/off) and analog (flow, humidity, pressure and temperature) sensing systems. These sensors are integrated into a programmable logic controller (PLC) which processes the data and establishes alarm levels and trigger points for maintenance activities. The system shall provide for multiple customer interfaces including a local HMI and/or provide the ability to tie into a customer&#39;s DCS or SCADA system. Additionally, the system shall be designed to be integrated with an SAS designed SCADA system. Further, the system has various troubleshooting alarms and preventive maintenance events for users to efficiently manage problems at an early stage. The alarms and events provide a series of displayed solutions to a particular problem enabling the user to fix the system without third party intervention. 
         [0023]    As is readily apparent, multiple HVAC units may be monitored by this system and present warnings or trigger events to a user from a number of units. The display information can be configured to respond to a plurality of units being monitored and supply troubleshooting instructions for each of the monitored units. 
         [0024]      FIG. 1  shows a block diagram of the interaction of a preferred embodiment of the present invention with a monitored system. PLC  2  receives raw sensor data from the monitored HVAC system and Sensing Package  4  and processes the date into useable digital data. PLC  2  establishes alarm and preventive maintenance after hours or “PM” levels as well. HVAC Unit and Sensing Package  4  is connected to the various equipment and sends the raw data to PLC  2 . PLC  2  in turn sends data to HMI  6  for local display of all monitored points and alarms. PLC  2  may also send data to a customer designed or custom DCS or SCADA system  8  for graphic display of all monitored point and alarms. 
         [0025]    A preferred embodiment of the system has a series of sensors including, but not limited to, system monitoring sensors for the following parameters: 
         [0026]    Airflow/Differential Pressure; 
         [0027]    Discharge/Supply Air Flow; 
         [0028]    Fresh Air/Stack Air Flow; 
         [0029]    Room Pressure (before filter); 
         [0030]    Stack Pre-Filter Pressure; and 
         [0031]    Stack Post-Filter Pressure. 
         [0032]    The system may also have motor sensors including the following: 
         [0033]    Evaporator Motor Current Transducer (CT); 
         [0034]    Condenser Motor Current Transducer (CT); 
         [0035]    Purge/Pressurization Motor Current Transducer (CT); 
         [0036]    Compressor Current Transducer (CT); and 
         [0037]    Heating Element Current Transducer (CT). 
         [0038]    The system may additionally have refrigerant system sensors including the following: 
         [0039]    Suction Pressure(s); 
         [0040]    Suction Temperature(s); 
         [0041]    Liquid Line Pressure(s); 
         [0042]    Liquid Line Temperature(s); 
         [0043]    Discharge Line Temperature(s); and 
         [0044]    Discharge Line Pressure(s). 
         [0045]    Additionally the system may have general performance sensors including the following: 
         [0046]    Room/Return Air Temperature(s)/RH; 
         [0047]    Discharge/Supply Air Temperature; 
         [0048]    Discharge/Supply Air RH; 
         [0049]    Room/Return Air Temperature/RH; 
         [0050]    Fresh Air Temperature/Fresh Air RH; 
         [0051]    Unit Incoming Voltage; 
         [0052]    Unit Incoming Phase (dry contact); and 
         [0053]    Unit Total Current. 
         [0054]    Turning now to  FIGS. 2A through 2F , a schematic  10  of a representative wiring diagram of a monitoring system of the present invention is shown. Panel  12  includes a programmable logic array  11  and display  13  for processing data collected from the HVAC system being monitored. Panel  12  is connected by Ethernet cable  14  to Ethernet switch  26 . Panel  12  is powered through lines  16  through junction block  18  which in turn is connected to fuse time delay  20 , connected to power supply  22  which is in turn connected via fuse time delay  24  to a power grid or electrical outlet. 
         [0055]    Ethernet switch  26  is interconnected via cable  28  which connects to Ethernet adapter  38  via connecting identifier A from  FIG. 4A to 4B . A series of input modules  40 ,  44 ,  46 ,  48 ,  50 ,  52 , and  54  are connected as further described below. Power is supplied to Ethernet adapter  38  via lines  30 , as well as supplied to strips  56  and  58 . 
         [0056]    Input module  40  is connected via identifier D by a ribbon cable  70  which connects to terminal block module  72 . DEC modules  74  are connected to strip  76  which in turn are connected to system shutdown signal to evaporator  78 , blower signal  80 , stage  1  cooling signal  81 , stage  1  heating signal  82 , stage  1  condenser fan cycle signal  84  and common side of control power transformer  86 . 
         [0057]    Ethernet cable  32  via identifier C is connected to an automation system terminal block module  60  which is in turn connected via Ethernet cable  62  to a second automation system terminal block module  64  connected by Ethernet cable  66  to power monitoring module  68 . 
         [0058]      FIG. 2B  shows Ethernet cable  34 , via identifier D connected to D on  FIG. 4C  and third terminal block module  72  as previously described. 
         [0059]      FIG. 2  shows stage  1  discharge line temperature sensor  94 , stage  1  liquid line temperature sensor  96  and stage  1  suction line temperature sensor  98  each connected to strip  92  and in turn connected to terminal block module  88  which is in turn connected via ribbon cable  36  to input module  40 . Data from temperature sensors  94 ,  96  and  98  are communicated by digital signal back to panel  12  and stored in memory. 
         [0060]    In similar fashion, supply air humidity/temperature transmitter  114 , return air humidity/temperature transmitter  116  and fresh air intake humidity/temperature transmitter  118  are connected lines through strip  112  via identifier F to input modules  46  and  48  for transmission of digital data to panel  12  for further processing. 
         [0061]      FIG. 2F  shows a number of sensors according to a preferred embodiment of the invention. Heater current sensor  138 , evaporator motor #1 current  140 , condenser motor #1 current  142  and stage  1  compressor current  144  are transmitted via strip  136  and  134  to input modules  52  and  54  for transmission of sensed information to panel  12  as described hereinabove. 
         [0062]    Similarly, fresh air post-filter sensor  146 , fresh pre-filter sensor  148 , building pressure sensor  150 , fresh air intake flow sensor  152  and supply air flow sensor  154  are connected to these functions on the HVAC unit to sense and transmit. 
         [0063]    Each of the foregoing sensors obtain real time data from the various sensed parameters and deliver via digital signal that data to the processor in panel  12 . The data is compared to pre-set data points stored in memory. 
         [0064]    Equipment types that may be monitored are set forth in Tables 1A and 1B. Tables 1A and 1B have common first two columns and present data for each of the Equipment Tag Names listed. Table 1 shows a sample instrument list of different manufacturer&#39;s products that may be sensed and monitored. Each is provided a unique Tag name which pertains to various characteristics of the system including instrument type, service description, manufacturer, model number, system provided part number, input/output type (which may be discrete or analog), signal type, power supply, certification, HAZLOC, Calibration ranges lo and hi, Engineering units, and other data. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 1A 
               
             
             
               
                   
               
               
                 Table One (A) 
               
             
          
           
               
                   
                 Instrument 
                 Service 
                 Manu- 
                 Model 
                 SAS 
                 IO 
                 Signal 
                 Power 
               
               
                 Tag Name 
                 Type 
                 Description 
                 facturer 
                 Number 
                 Part # 
                 Type 
                 Type 
                 Supply 
               
               
                   
               
               
                 XS_10001 
                 N/A 
                 System 
                 N/A 
                 N/A 
                 N/A 
                 DI 
                 24 
                 24 
               
               
                   
                   
                 Shutdown Signal 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 XS_10002 
                 N/A 
                 Evaporator 
                 N/A 
                 N/A 
                 N/A 
                 DI 
                 24 
                 24 
               
               
                   
                   
                 Blower Signal 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 XS_10003 
                 N/A 
                 Stage 1 Cooling 
                 N/A 
                 N/A 
                 N/A 
                 DI 
                 24 
                 24 
               
               
                   
                   
                 Signal 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 XS_10004 
                 N/A 
                 Stage 2 Cooling 
                 N/A 
                 N/A 
                 N/A 
                 DI 
                 24 
                 24 
               
               
                   
                   
                 Signal 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 XS_10005 
                 N/A 
                 Stage 1 Heating 
                 N/A 
                 N/A 
                 N/A 
                 DI 
                 24 
                 24 
               
               
                   
                   
                 Signal 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 XS_10006 
                 N/A 
                 Stage 2 Heating 
                 N/A 
                 N/A 
                 N/A 
                 DI 
                 24 
                 24 
               
               
                   
                   
                 Signal 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 XS_10007 
                 N/A 
                 Stage 1 Condenser 
                 N/A 
                 N/A 
                 N/A 
                 DI 
                 24 
                 24 
               
               
                   
                   
                 Fan Cycle Signal 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 XS_10008 
                 N/A 
                 Stage 2 Condenser 
                 N/A 
                 N/A 
                 N/A 
                 DI 
                 24 
                 24 
               
               
                   
                   
                 Fan Cycle Signal 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 XS_10009 
                 N/A 
                 Pressurization 
                 N/A 
                 N/A 
                 N/A 
                 DI 
                 24 
                 24 
               
               
                   
                   
                 System Enable 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                   
                   
                 Signal 
               
               
                 RTD_10010 
                 RTD 
                 Stage 1 Discharge 
                 Turck 
                 TP-203A- 
                 100726 
                 AI 
                 RTD 
                 N/A 
               
               
                   
                   
                 Line Temperature 
                   
                 CF-H1141- 
               
               
                   
                   
                   
                   
                 L100 
               
               
                 RTD_10011 
                 RTD 
                 Stage 1 Liquid 
                 Turck 
                 TP-203A- 
                 100726 
                 AI 
                 RTD 
                 N/A 
               
               
                   
                   
                 Line Temperature 
                   
                 CF-H1141- 
               
               
                   
                   
                   
                   
                 L100 
               
               
                 RTD_10012 
                 RTD 
                 Stage 1 Suction 
                 Turck 
                 TP-203A- 
                 100726 
                 AI 
                 RTD 
                 N/A 
               
               
                   
                   
                 Line Temperature 
                   
                 CF-H1141- 
               
               
                   
                   
                   
                   
                 L100 
               
               
                 RTD_10013 
                 RTD 
                 Stage 2 Discharge 
                 Turck 
                 TP-203A- 
                 100726 
                 AI 
                 RTD 
                 N/A 
               
               
                   
                   
                 Line Temperature 
                   
                 CF-H1141- 
               
               
                   
                   
                   
                   
                 L100 
               
               
                 RTD_10014 
                 RTD 
                 Stage 2 Liquid 
                 Turck 
                 TP-203A- 
                 100726 
                 AI 
                 RTD 
                 N/A 
               
               
                   
                   
                 Line Temperature 
                   
                 CF-H1141- 
               
               
                   
                   
                   
                   
                 L100 
               
               
                 RTD_10015 
                 RTD 
                 Stage 2 Suction 
                 Turck 
                 TP-203A- 
                 100726 
                 AI 
                 RTD 
                 N/A 
               
               
                   
                   
                 Line Temperature 
                   
                 CF-H1141- 
               
               
                   
                   
                   
                   
                 L100 
               
               
                 HT_10016 
                 Humidity 
                 Supply Air 
                 Minco 
                 AH439D 
                 100831 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Humidity 
                   
                 1S20EN 
                   
                   
                 mA 
                 VDC 
               
               
                   
                   
                 Transmitter 
                   
                 T2 
               
               
                 TT_10017 
                 Temperature 
                 Supply Air 
                 Minco 
                 AH439D 
                 100831 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Temperature 
                   
                 1S20EN 
                   
                   
                 mA 
                 VDC 
               
               
                   
                   
                 Transmitter 
                   
                 T2 
               
               
                 HT_10018 
                 Humidity 
                 Return Air 
                 Minco 
                 AH439D 
                 100831 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Humidity 
                   
                 1S20EN 
                   
                   
                 mA 
                 VDC 
               
               
                   
                   
                 Transmitter 
                   
                 T2 
               
               
                 TT_10019 
                 Temperature 
                 Return Air 
                 Minco 
                 AH439D 
                 100831 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Temperature 
                   
                 1S20EN 
                   
                   
                 mA 
                 VDC 
               
               
                   
                   
                 Transmitter 
                   
                 T2 
               
               
                 HT_10020 
                 Humidity 
                 Fresh Air Intake 
                 Minco 
                 AH439D 
                 100831 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Humidity 
                   
                 1S20EN 
                   
                   
                 mA 
                 VDC 
               
               
                   
                   
                 Transmitter 
                   
                 T2 
               
               
                 TT_10021 
                 Temperature 
                 Fresh Air Intake 
                 Minco 
                 AH439D 
                 100831 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Temperature 
                   
                 1S20EN 
                   
                   
                 mA 
                 VDC 
               
               
                   
                   
                 Transmitter 
                   
                 T2 
               
               
                 PT_10022 
                 Pressure 
                 Stage 1 Discharge 
                 Johnson 
                 P499AC 
                 109086 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Line Pressure 
                 Controls 
                 P-107K 
                   
                   
                 mA 
                 VDC 
               
               
                 PT_10023 
                 Pressure 
                 Stage 1 Liquid 
                 Johnson 
                 P499AC 
                 109086 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Line Pressure 
                 Controls 
                 P-107K 
                   
                   
                 mA 
                 VDC 
               
               
                 PT_10024 
                 Pressure 
                 Stage 1 Suction 
                 Johnson 
                 P499AC 
                 109086 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Line Pressure 
                 Controls 
                 P-107K 
                   
                   
                 mA 
                 VDC 
               
               
                 PT_10025 
                 Pressure 
                 Stage 2 Discharge 
                 Johnson 
                 P499AC 
                 109086 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Lane Pressure 
                 Controls 
                 P-107K 
                   
                   
                 mA 
                 VDC 
               
               
                 PT_10026 
                 Pressure 
                 Stage 2 Liquid 
                 Johnson 
                 P499AC 
                 109086 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Line Pressure 
                 Controls 
                 P-107K 
                   
                   
                 mA 
                 VDC 
               
               
                 PT_10027 
                 Pressure 
                 Stage 2 Suction 
                 Johnson 
                 P499AC 
                 109086 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Transmitter 
                 Line Pressure 
                 Controls 
                 P-107K 
                   
                   
                 mA 
                 VDC 
               
               
                 PDT_10028 
                 Differential 
                 Building Pressure 
                 Dwyer 
                 MS2- 
                 100733 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Pressure 
                 DP 
                   
                 W102- 
                   
                   
                 mA 
                 VDC 
               
               
                   
                 Transmitter 
                   
                   
                 LCD 
               
               
                 PDT_10029 
                 Differential 
                 Fresh Air Intake 
                 Dwyer 
                 MS2- 
                 100733 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Pressure 
                 Flow DP 
                   
                 W102- 
                   
                   
                 mA 
                 VDC 
               
               
                   
                 Transmitter 
                   
                   
                 LCD 
               
               
                 PDT_10030 
                 Differential 
                 Supply Air Flow 
                 Dwyer 
                 MS2- 
                 100733 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Pressure 
                 DP 
                   
                 W102- 
                   
                   
                 mA 
                 VDC 
               
               
                   
                 Transmitter 
                   
                   
                 LCD 
               
               
                 PDT_10031 
                 Differential 
                 Fresh Air Post- 
                 Dwyer 
                 MS2- 
                 100733 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Pressure 
                 Filter DP 
                   
                 W102- 
                   
                   
                 mA 
                 VDC 
               
               
                   
                 Transmitter 
                   
                   
                 LCD 
               
               
                 PDT_10032 
                 Differential 
                 Fresh Air Pre- 
                 Dwyer 
                 MS2- 
                 100733 
                 AI 
                 4-20 
                 24 
               
               
                   
                 Pressure 
                 Filter DP 
                   
                 W102- 
                   
                   
                 mA 
                 VDC 
               
               
                   
                 Transmitter 
                   
                   
                 LCD 
               
               
                 CT_10033 
                 Current 
                 Stage 1 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 Compressor 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                   
                   
                 Current 
               
               
                 CT_10034 
                 Current 
                 Stage 2 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 Compressor 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                   
                   
                 Current 
               
               
                 CT_10035 
                 Current 
                 Condenser Motor 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 #1 Current 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 CT_10036 
                 Current 
                 Condenser Motor 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 #2 Current 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 CT_10037 
                 Current 
                 Evaporator Motor 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 #1 Current 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 CT_10038 
                 Current 
                 Evaporator Motor 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 #2 Current 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 CT_10039 
                 Current 
                 Evaporator Motor 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 #3 Current 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 CT_10040 
                 Current 
                 Stage 1 Heater 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 Current 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 CT_10041 
                 Current 
                 Stage 2 Heater 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 Current 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 CT_10042 
                 Current 
                 Pressurization 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 Motor #1 Current 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                 CT_10043 
                 Current 
                 Pressurization 
                 Dwyer 
                 LTTJ-020 
                 100720 
                 AI 
                 0-10 
                 24 
               
               
                   
                 Transducer 
                 Motor #2 Current 
                   
                   
                   
                   
                 VDC 
                 VDC 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 1B 
               
             
             
               
                   
               
               
                 Table One (B) 
               
             
          
           
               
                 Tag 
                 Instrument 
                 Certifi- 
                 HAZ- 
                 Calibration 
                 Calibration 
                 Engineering 
                   
                   
                   
               
               
                 Name 
                 Type 
                 cation 
                 LOC 
                 Range Lo 
                 Range Hi 
                 Units 
                 Rack 
                 Slot 
                 Point 
               
               
                   
               
             
          
           
               
                 XS_10001 
                 N/A 
                 N/A 
                   
                 0 
                 1 
                 N/A 
                 1 
                 1 
                 1 
               
               
                 XS_10002 
                 N/A 
                 N/A 
                   
                 0 
                 1 
                 N/A 
                 1 
                 1 
                 2 
               
               
                 XS_10003 
                 N/A 
                 N/A 
                   
                 0 
                 1 
                 N/A 
                 1 
                 1 
                 3 
               
               
                 XS_10004 
                 N/A 
                 N/A 
                   
                 0 
                 1 
                 N/A 
                 1 
                 1 
                 4 
               
               
                 XS_10005 
                 N/A 
                 N/A 
                   
                 0 
                 1 
                 N/A 
                 1 
                 1 
                 5 
               
               
                 XS_10006 
                 N/A 
                 N/A 
                   
                 0 
                 1 
                 N/A 
                 1 
                 1 
                 6 
               
               
                 XS_10007 
                 N/A 
                 N/A 
                   
                 0 
                 1 
                 N/A 
                 1 
                 1 
                 7 
               
               
                 XS_10008 
                 N/A 
                 N/A 
                   
                 0 
                 1 
                 N/A 
                 1 
                 1 
                 8 
               
               
                 XS_10009 
                 N/A 
                 N/A 
                   
                 0 
                 1 
                 N/A 
                 1 
                 1 
                 10 
               
               
                 RTD_10010 
                 RTD 
                   
                   
                 −22 
                 662 
                 ° F. 
                 1 
                 3 
                 4 
               
               
                 RTD_10011 
                 RTD 
                   
                   
                 −22 
                 662 
                 ° F. 
                 1 
                 3 
                 5 
               
               
                 RTD_10012 
                 RTD 
                   
                   
                 −22 
                 662 
                 ° F. 
                 1 
                 3 
                 3 
               
               
                 RTD_10013 
                 RTD 
                   
                   
                 −22 
                 662 
                 ° F. 
                 1 
                 3 
                 4 
               
               
                 RTD_10014 
                 RTD 
                   
                   
                 −22 
                 662 
                 ° F. 
                 1 
                 3 
                 5 
               
               
                 RTD_10015 
                 RTD 
                   
                   
                 −22 
                 662 
                 ° F. 
                 1 
                 3 
                 6 
               
               
                 HT_10016 
                 Humidity 
                   
                   
                 0 
                 100 
                 % 
                 1 
                 4 
                 1 
               
               
                   
                 Transmitter 
               
               
                 TT_10017 
                 Temperature 
                   
                   
                 −20 
                 140 
                 ° F. 
                 1 
                 4 
                 2 
               
               
                   
                 Transmitter 
               
               
                 HT_10018 
                 Humidity 
                   
                   
                 0 
                 100 
                 % 
                 1 
                 4 
                 3 
               
               
                   
                 Transmitter 
               
               
                 TT_10019 
                 Temperature 
                   
                   
                 −20 
                 140 
                 ° F. 
                 1 
                 4 
                 4 
               
               
                   
                 Transmitter 
               
               
                 HT_10020 
                 Humidity 
                   
                   
                 0 
                 100 
                 % 
                 1 
                 4 
                 2 
               
               
                   
                 Transmitter 
               
               
                 TT_10021 
                 Temperature 
                   
                   
                 −20 
                 140 
                 ° F. 
                 1 
                 4 
                 6 
               
               
                   
                 Transmitter 
               
               
                 PT_10022 
                 Pressure 
                 CE/UL 
                 CID2 
                 0 
                 750 
                 PSI 
                 1 
                 4 
                 7 
               
               
                   
                 Transmitter 
               
               
                 PT_10023 
                 Pressure 
                 CE/UL 
                 CID2 
                 0 
                 750 
                 PSI 
                 1 
                 4 
                 8 
               
               
                   
                 Transmitter 
               
               
                 PT_10024 
                 Pressure 
                 CE/UL 
                 CID2 
                 0 
                 750 
                 PSI 
                 1 
                 5 
                 1 
               
               
                   
                 Transmitter 
               
               
                 PT_10025 
                 Pressure 
                 CE/UL 
                 CID2 
                 0 
                 750 
                 PSI 
                 1 
                 5 
                 2 
               
               
                   
                 Transmitter 
               
               
                 PT_10026 
                 Pressure 
                 CE/UL 
                 CID2 
                 0 
                 750 
                 PSI 
                 1 
                 5 
                 3 
               
               
                   
                 Transmitter 
               
               
                 PT_10027 
                 Pressure 
                 CE/UL 
                 CID2 
                 0 
                 750 
                 PSI 
                 1 
                 5 
                 4 
               
               
                   
                 Transmitter 
               
               
                 PDT_10028 
                 Differential 
                 CE 
                   
                 0 
                 1250 
                 Pascals 
                 1 
                 5 
                 5 
               
               
                   
                 Pressure 
               
               
                   
                 Transmitter 
               
               
                 PDT_10029 
                 Differential 
                 CE 
                   
                 0 
                 1250 
                 Pascals 
                 1 
                 5 
                 6 
               
               
                   
                 Pressure 
               
               
                   
                 Transmitter 
               
               
                 PDT_10030 
                 Differential 
                 CE 
                   
                 0 
                 1250 
                 Pascals 
                 1 
                 5 
                 7 
               
               
                   
                 Pressure 
               
               
                   
                 Transmitter 
               
               
                 PDT_10031 
                 Differential 
                 CE 
                   
                 0 
                 1250 
                 Pascals 
                 1 
                 5 
                 8 
               
               
                   
                 Pressure 
               
               
                   
                 Transmitter 
               
               
                 PDT_10032 
                 Differential 
                 CE 
                   
                 0 
                 1250 
                 Pascals 
                 1 
                 6 
                 1 
               
               
                   
                 Pressure 
               
               
                   
                 Transmitter 
               
               
                 CT_10033 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 1 
               
               
                   
                 Transducer 
               
               
                 CT_10034 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 2 
               
               
                   
                 Transducer 
               
               
                 CT_10035 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 3 
               
               
                   
                 Transducer 
               
               
                 CT_10036 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 4 
               
               
                   
                 Transducer 
               
               
                 CT_10037 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 5 
               
               
                   
                 Transducer 
               
               
                 CT_10038 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 6 
               
               
                   
                 Transducer 
               
               
                 CT_10039 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 7 
               
               
                   
                 Transducer 
               
               
                 CT_10040 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 8 
               
               
                   
                 Transducer 
               
               
                 CT_10041 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 1 
               
               
                   
                 Transducer 
               
               
                 CT_10042 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 2 
               
               
                   
                 Transducer 
               
               
                 CT_10043 
                 Current 
                   
                   
                 0 
                 100 
                 Amperes 
                 1 
                 7 
                 3 
               
               
                   
                 Transducer 
               
               
                   
               
             
          
         
       
     
         [0065]    Each of the sensors identified in  FIG. 2 , may have various set points and acceptable ranges. These set points and ranges are relatable to one or more Events which the system generates for troubleshooting. Table 2 sets forth a list of sensors, acceptable parameter rates in Hi SP and Lo SP columns and Events that pertain to those sensed parameters. 
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Table 2 
               
             
          
           
               
                   
                 IO 
                 Signal 
                 Power 
                 Engineering 
                   
                   
                   
               
               
                 Item Description 
                 Type 
                 Type 
                 Supply 
                 Units 
                 Hi SP 
                 Lo SP 
                 Events 
               
               
                   
               
             
          
           
               
                 Calculated Superheat 
                 N/A 
                 Calc 
                 N/A 
                 ° F. 
                 20 
                 10 
                 1-6, 9-14 
               
               
                 Calculated Subcooling 
                 N/A 
                 Calc 
                 N/A 
                 ° F. 
                 20 
                 10 
                 1-4, 7-12, 15, 16 
               
               
                 Compressor Current 
                 AI 
                 4-20 mA 
                 24 VDC 
                 % AMPERES 
                 125 
                 25 
                 17, 18 
               
               
                 (Note 1) 
               
               
                 Condenser/ 
                 AI 
                 4-20 mA 
                 24 VDC 
                 % AMPERES 
                 90 
                 25 
                 19-23, 26, 27 
               
               
                 Evaporator/Purge 
               
               
                 Motor Current 
               
               
                 (Note 2) 
               
               
                 Heater Current 
                 AI 
                 4-20 mA 
                 24 VDC 
                 % AMPERES 
                 125 
                 75 
                 24, 25 
               
               
                 (Note 3) 
               
               
                 Room/Building/ 
                 AI 
                 4-20 mA 
                 24 VDC 
                 IWC 
                 0.25 
                 0.1 
                 30 
               
               
                 Shelter/Enclosure/ 
               
               
                 Cabinet Pressure 
               
               
                 Room/Building/ 
                 AI 
                 4-20 mA 
                 24 VDC 
                 ° F. 
                 85 
                 55 
                 31, 77 
               
               
                 Shelter/Enclosure/ 
               
               
                 Cabinet Temperature 
               
               
                 Discharge Air 
                 AI 
                 4-20 mA 
                 24 VDC 
                 ° F. 
                 192 
                 N/A 
                 32 
               
               
                 Temperature 
               
               
                 Incoming Voltage 
                 AI 
                 4-20 mA 
                 24 VDC 
                 % VOLTS 
                 110 
                 90 
                 33, 73-76 
               
               
                 (Note 4) 
               
               
                 Contactor Cycle Limit 
                 N/A 
                 Calc 
                 N/A 
                 COUNTS 
                 100000 
                 N/A 
                 40-50 
               
               
                 Pre-Filter Differential 
                 AI 
                 4-20 mA 
                 24 VDC 
                 IWC 
                 0.2 
                 N/A 
                 78 
               
               
                 Pressure 
               
               
                 Post-Filter Differential 
                 AI 
                 4-20 mA 
                 24 VDC 
                 IWC 
                 0.2 
                 N/A 
                 79 
               
               
                 Pressure 
               
               
                 Discharge Refrigerant 
                 AI 
                 4-20 mA 
                 24 VDC 
                 PSI 
                 575 
                 N/A 
                 34, 35 
               
               
                 Pressure (Note 5) 
               
               
                 Suction Refrigerant 
                 AI 
                 4-20 mA 
                 24 VDC 
                 PSI 
                 N/A 
                 20 
                 36, 37 
               
               
                 Pressure (Note 6) 
               
               
                 Fresh Air Flow 
                 AI 
                 4-20 mA 
                 24 VDC 
                 % CFM 
                 120 
                 80 
                 28 
               
               
                 (NOTE 7) 
               
               
                 Discharge Air Flow 
                 AI 
                 4-20 mA 
                 2 4VDC 
                 % CFM 
                 120 
                 80 
                 29 
               
               
                 (NOTE 8) 
               
               
                   
               
               
                 (NOTE 1): 
               
               
                 COMPRESSOR CURRENT ALARM SETPOINTS ARE EXPRESSED AS A PERCENTAGE OF COMPRESSOR&#39;S RATED RUN LOAD AMPS (RLA). 
               
               
                 (NOTE 2): 
               
               
                 MOTOR CURRENT ALARM SETPOINTS ARE EXPRESSED AS A PERCENTAGE OF MOTOR&#39;S RATED FULL LOAD AMPS (FLA). 
               
               
                 (NOTE 3): 
               
               
                 HEATER CURRENT ALARM SETPOINTS ARE EXPRESSED AS A PERCENTAGE OF HEATER&#39;S CALCULATED CURRENT BASED ON ITS RATED WATTAGE. 
               
               
                 (NOTE 4): 
               
               
                 VOLTAGE ALARM SETPOINTS ARE EXPRESSED AS A PERCENTAGE OF RATED SYSTEM VOLTAGE. 
               
               
                 (NOTE 5): 
               
               
                 DISCHARGE LINE PRESSURE ALARM SETPOINTS ARE DIFFERENT FOR EACH REFRIGERANT TYPE. 
               
               
                 (NOTE 5): 
               
               
                 SUCTION LINE PRESSURE ALARM SETPOINTS ARE DIFFERENT FOR EACH REFRIGERANT TYPE. 
               
               
                 (NOTE 7): 
               
               
                 FRESH AIR FLOW RATE IS DEPENDENT ON SYSTEM DESIGN PURGE AND/OR BUILDING LEAKAGE REQUIREMENTS. 
               
               
                 (NOTE 8): 
               
               
                 DISCHARGE AIR FLOW RATE IS DEPENDENT ON REFRIGERATION TONNAGE. 
               
             
          
         
       
     
         [0066]    So for example, compressor current set points are shown as a percentage of the compressor&#39;s rated run load in amperes. Each item that is being sensed has high and low parameters that when triggered feed information into the processor to determine which of the Events are occurring. For example, Heater Current is expressed in amperes and if it deviates from the acceptable range by 125% or 75%, it will produce a display of Event  24  or  25  depending on additional data. Then Event  24  will display on the screen and provide the user with troubleshooting information. 
         [0067]      FIGS. 3 through 10  show troubleshooting information displays for various events that may be monitored by the system of the preferred embodiment of the invention. Various sensing parameters will be processed into individual actionable events for the purpose of ease of interpretation and maintenance. For example, in  FIG. 3A , Event  01  is a tag name given to the event description—“Stage  1  high superheat and low subcool detected,” which is computed from suction and liquid line pressures and temperatures. Each event is similarly provided a unique tag for processing by the PLC and system. 
         [0068]    For each event, a preventive maintenance alert and/or troubleshooting guide is provided as exemplified below  FIGS. 3 through 10 . 
         [0069]    Monitoring/Alarm Functions are provided to analyze Airflow/Pressure. Using analog data from airflow and pressure sensors allows for the following to be monitored: dirty filter monitoring; dirty coil monitoring (indicated by refrigerant pressures); statement of unit performance; total delivered tons (calculated); total delivered CFM to conditioned space (measured); total return air CFM (calculated); total fresh air CFM (measured); and the number of air changes per hour (requires user input of building parameters). 
         [0070]    In a preferred embodiment, motor ON/OFF and current transducers are provided. These permit monitoring of the motor current using a CT (single leg) of all motor driven components and allows for display of all components that are on and off; the motor current using a CT (single leg) of all motor driven components and a relay on the contactor can display an alarm if the motor is called for, but not engaged; the motor current using a CT (single leg) of all motor driven components can determine the ON/OFF status and allows for run timers to be established for each component which can trigger maintenance activities (such as greasing motors or PM checks); the motor current using a CT (single leg) of all motor driven components can determine the run status and establishes the number of starts on the component which can trigger maintenance activities (i.e. excessive motor or compressor starts per hour or contactor life); and the motor current using a CT (single leg) of all motor driven components can allow for comparison against nameplate FLA vs. actual running current. When a component draws more amps than FLA plus service factor, a maintenance activity will be triggered. 
         [0071]    The Refrigerant System is monitored by monitoring the pressure and temperature of refrigerant charge which allows for the calculation and display of each system&#39;s superheat and subcool to indicate refrigeration system health and allow for scheduled maintenance and, if necessary, shutdown for repair if a leak is found. Superheat and subcool levels will be displayed and alarms generated on out of range conditions. For example, high refrigerant discharge pressures can indicate condenser blockage, condenser fan problems, or dirty condenser coil; low refrigerant suction pressures can indicate evaporator blockage, evaporator fan problems, coil icing, dirty return air filter, or dirty evaporator coil. 
         [0072]    The Heater System may be monitored by monitoring the current draw of one leg of the heater wiring and the discharge temperature. The unit&#39;s incoming voltage can also allow for the display of each heater stage status and total delivered heating kW to the space. 
         [0073]    General Performance can be monitored by measuring the temperature and RH of the conditioned space and allows for the display of the unit&#39;s general performance and can trigger alarms when temperatures and RH are out of range. Table 2 shows a list of typical parameters and the set points being measured against. For each parameter being sensed, there are set points of a preferred operating range as shown in Table 2. If the processor detects a sensed data that is different than pre-determined settings, it enters that data into the PLC to determine if it alone, or in combination with other sensed signals, triggers an event. For example, certain events are the result of a deviation from two sensor readings. Event  1  is triggered by a sensor reading of the calculated superheat being too high or low and the calculated subcooling being too high or low as set forth in Table 2. In other situations, Event  34  is triggered by the discharge refrigerant pressure being out of a pre-determined range. 
         [0074]    Data Gathering/Processing and Sensor Data Gathering may be monitored as well. 
         [0075]    The sensor data shall be gathered into a single PLC. The PLC will gather all analog and digital sensor data and process it into useful data. 
         [0076]    Sensor Processing is accomplished with a PLC program shall be written to take raw data and establish the following: 
         [0077]    Filter Δp monitoring and dirty filter alarm levels; 
         [0078]    Calculated Return Airflow with alarm (low and high); 
         [0079]    Fresh Air Airflow with alarm (low and high); 
         [0080]    Discharge/Supply Airflow with alarm (low and high); 
         [0081]    Number of Air Changes calculation with alarm (low and high); 
         [0082]    Supply Air Pressure with alarm level (high); 
         [0083]    Room Pressure with alarm level (low and high); 
         [0084]    Run time for each component with PM levels after established threshold has been met; 
         [0085]    Number of ON/OFF cycles for each contactor component with PM levels after established threshold has been met; 
         [0086]    Motor current display with alarm levels based on RLA or FLA (plus service factor) input; 
         [0087]    Refrigerant system superheat and subcool calculation and display with alarm levels (high and low); 
         [0088]    Iced/Blocked/Dirty Coil alarms based on refrigerant pressures; 
         [0089]    Heat system ON/OFF with unit voltage and heater current to calculate actual delivered kW to space; and 
         [0090]    Temperature sensor reporting and calculation of actual delivered capacity in kW, Btu/Hr and tons. 
         [0091]    Alarms shall be established when delivered air temperatures are out of range. 
         [0092]    Local Human Machine Interface “HMI” Display may have the following displays: 
         [0093]    Filter Δp gauges with red zones for alarm levels and dirty filter alarm ON/OFF; 
         [0094]    Return Airflow Gauge with red zones for alarm levels and low return air alarm ON/OFF; 
         [0095]    Fresh Air Airflow Gauge with red zones for alarm levels (low and high) and low and high alarms; 
         [0096]    Discharge/Supply Airflow Gauge with red zones for alarm levels (low and high) and low and high alarms; 
         [0097]    Number of Air Changes display with alarm level for low and high number of air changes; 
         [0098]    Room Pressure gauge with red zone for high and low levels with high and low alarm indicators; 
         [0099]    Run time display for each component with PM level indicators; 
         [0100]    Number of ON/OFF cycles display for each component with PM levels indicator. Alarm displayed if any motor/heater contactor is called for, but not engaged; 
         [0101]    Motor current draw display for each motor and with high alarm level indicator; 
         [0102]    Refrigerant system superheat and subcool display with high and low alarm levels; 
         [0103]    Refrigerant system gauges with out of range indicators (iced, blocked or dirty coil); 
         [0104]    Heat system ON/OFF display with total current display and display of actual delivered kW. Alarm displayed if heater contactor is called for, but not engaged; 
         [0105]    Temperature reading displays with normal alarm levels of out of range values. Display of actual delivered capacity in kW, Btu/Hr and/or tons; 
         [0106]    Trending display for all sensors; 
         [0107]    Historical display of all sensors up to a pre-determined time period; and 
         [0108]    Alarm log for all alarms and preventive maintenance alerts. 
         [0109]    In certain cases, the system processor will analyze trending data and check against pre-determined set points for activation of Event and troubleshooting or maintenance instructions. For example, if the system aggregates data showing a temperature sensor reading downward over a specified period of time, it may indicate a potential problem and based on that trend, the processor will match to a pre-determined event and generate an appropriate display for resolution. 
         [0110]      FIGS. 3 through 10  show a number of Events triggered by various combinations of sensed data from the various sensors employed in the system. Each Event listing is stored in memory and tied to a set of instructions or troubleshooting guides that responds to alarms and provides maintenance advice when various factors reach certain milestones or otherwise trigger an Event. When the Event occurs, it matches the stored instructions with one or more sensed data readings to display the Event and troubleshooting guide for the user to review and execute. A particular Event may have several solutions or a series of solutions that may be tried one after the other to solve the problem. 
         [0111]    Each Event is identified by Title, Possible Causes, and Recommended Solutions to generate a display of the particular Event in response to the pre-determined set points in comparison to the sensed data. 
         [0112]    For example, as shown in  FIG. 10H , Event  98  illustrates a continuous trend analysis, while the amperage has not exceeded limits, the uptrend demonstrate a deteriorating motor and we recommend action before failure. Event  99  illustrates a frequent occurrence within a specified amount of time. In this case, frequent voltage irregularities call for either a source fix, or a power quality enhancement on the load side. Event  100  illustrates a comparison of two identical and redundant units serving a common air conditioned space. One operating at lower efficiency than the other calls for maintenance checks. Event  101  illustrates a timed preventive maintenance event even in the absence of a sensor variance, recommended for continued smooth operation. 
         [0113]    Certain Events may be triggered for maintenance purposes before an actual problem arises. In this case, sensor variances or trends may be analyzed against pre-determined points and matched to a display of an Event. Similarly, maintenance events may be triggered based on run time independent of any sensed data or trends and appropriate display triggered for the user. As previously discussed, Events may be configured for any of a variety of sensors and conditions with appropriate troubleshooting or maintenance solutions stored in memory for retrieval and display to a user. 
         [0114]    While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the later filed claims.