MicroTech Water-Cooled Screw Chiller Controller

Transcription

1 BACnet Data Information Packet BD 02-8 Group: Controls Date: January 2003 MicroTech Water-Cooled Screw Chiller Controller Point mapping data for the MicroTech BACdrop Gateway with PMF version 1.10 software and the following MicroTech water-cooled screw chiller applications: B vintage (models PFS-B) C vintage (models WHS and PFS-C) Contents Revision History... 2 Overview... 3 Introduction... 3 Network Configuration... 3 Software Identification and Compatibility... 3 BACdrop Software: The PMF File... 3 MicroTech Controller Software: IDENTs... 3 Compatibility... 4 Supplemental Literature... 5 Conversions and Conventions... 5 B-Vintage Water-Cooled Screw Chiller... 6 Analog Value Objects... 6 Analog Input Objects Analog Output Objects Binary Input Objects Binary Output Objects C-Vintage Water-Cooled Screw Chiller Analog Value Objects Analog Input Objects Analog Output Objects Binary Input Objects Binary Output Objects McQuay International

2 Revision History Version Initial release. For PMF version Version No changes to point mapping data. For PMF versions 1.01 through Version No changes to point mapping data. For PMF versions 1.01 through Version No changes to point mapping data. For PMF versions 1.01 through Version For PMF version PFS-B: Changed the OAT AI object from low resolution to high resolution and changed its name. Added alarm data objects for current alarm. Added a previous alarm object. Changed the order of all AV objects. Changed the units and object name for the refrigerant leak detection AI. Changed the names of several AV and AI objects for consistency and clarity. Changed the name of the chilled water setpoint object (AO3) and the BAS OAT object (AO5) for consistency with keypad and IM documentation. Deleted the OutdoorAirTempMethod object (old AO6). Deleted the CondEvapRatio object (old AV40). Changed the name of the clear alarm BO object. PFS-C/WHS: Added alarm data objects for current circuit alarms. Added previous circuit alarm objects. Added saturated condenser and evaporator temp AV objects. Deleted the condenser pump and evaporator pump hours AV objects since the controller does not track them. Added compressor start totalization AV objects. Deleted the last compressor start and stop time-stamp AV objects because the data is updated whenever either compressor starts or stops confusing and of little value. Changed the order of all AV objects. Changed the units and object name for the refrigerant leak detection AI. Changed the names of several AV and AI objects for consistency and clarity. Fixed a mapping error for the liquid line pressure AI. Changed the name of the chilled water setpoint object (AO1) and the BAS OAT object (AO9) for consistency with keypad and IM documentation. Deleted the OutdoorAirTemp- Method object (old AO6). Changed the names of the clear alarm BO objects. Version No changes to point mapping data. For PMF versions 1.06 and Version No changes to point mapping data. For PMF versions 1.06 through See updated software compatibility table on page 4. Version No changes to point mapping data. For PMF versions 1.09 and Minor editorial changes. Notice Copyright 2003 McQuay International, Minneapolis, MN. All rights reserved throughout the world. McQuay International reserves the right to change any information contained herein without prior notice. No guarantees are given as to the accuracy of the information provided. McQuay and MicroTech are registered trademarks of McQuay International. BACdrop and Monitor are trademarks of McQuay International. All other trademarks are the property of their respective owners. 2 BD 02-8

3 Overview Introduction The MicroTech BACdrop Gateway integrates a MicroTech network into a BACnet building automation system (BAS) network so that you can monitor and control McQuay International equipment from the BAS network. The gateway translates between BACnet variables on an Ethernet network and McQuay memory locations on the proprietary McQuay network. This document provides point mapping information for the MicroTech water-cooled screw chiller applications used in models PFS-B, PFS-C, and WHS. For other MicroTech applications, refer to the appropriate BACnet Data Information Packet documentation. Network Configuration The BACnet network interface to the BACdrop gateway must be Ethernet, 10BaseT. Once the MicroTech network has been commissioned (typically by a McQuay representative), the BAS vendor can connect the Ethernet network to the BACdrop gateway. The network must be intact for the BAS to control the chillers; however, the chillers are capable of operating even if communications with the BAS are lost. For more information, refer to IM 689, MicroTech BACdrop Gateway. It is worth noting here that the B-vintage chiller has two MicroTech controllers (one for each compressor) and the C vintage chiller has one MicroTech controller. Refer to the chiller documentation for more information (see Supplemental Literature below). Software Identification and Compatibility It is extremely important that compatibility be maintained between the software in the BACdrop gateway and its associated MicroTech controllers. This section provides information about software compatibility for both current and old releases of BACdrop and MicroTech software. New releases of BACdrop software and the BACnet Data Information Packets will be made available on the McQuay International bulletin board system called McQuay OnLine. For access to McQuay OnLine, contact the McQuay Controls group in Minneapolis. BACdrop Software: The PMF File The BACdrop gateway contains a single point mapping file (PMF) that contains specific point mapping information for MicroTech control applications. The standard PMF file contains all currently supported standard MicroTech control applications. This BACnet Data Information Packet (BDIP) describes only the portion of the standard PMF that pertains to standard MicroTech watercooled screw chiller applications. Other BDIPs describe other portions of the PMF file and other MicroTech applications. Custom PMF files can be written for custom MicroTech control applications, but in such instances the information in this document may not apply. Custom PMF files will have an x in their names; e.g., PMFx122. MicroTech Controller Software: IDENTs All MicroTech application software is labeled with an IDENT. In most cases, the IDENT has a nomenclature scheme, which is described in the installation and operation manuals for the controller. The last two or three characters of the IDENT are always used to denote the version and revision of the software. For example, the characters 03G would mean revision G of the third version. In general, the revision level is incremented for very minor changes and the version level is incremented for major changes. BD

4 The IDENT can be read from a MicroTech controller in one of four ways: 1. Using the keypad/display If a MicroTech controller is equipped with a keypad/display, you can use it to find the IDENT (except on series-100 centrifugal chillers). 2. Using the BACdrop commissioning software A network diagnostic can be used to show the IDENTs. 3. Using MicroTech Monitor software If Monitor software is available, it will typically show the IDENT on an application screen. Or a network diagnostic can be used to show the IDENTs. The read/write memory function can also be used to read IDENTs directly from memory. 4. Using the BACnet BAS From the BACnet side of the gateway, an IDENT can be read in the property Application_Software_Version, which is part of the DEVICE object for the MicroTech controller. Compatibility The PMF file contains a detailed map that associates BACnet objects with the memory locations and functions within the MicroTech controllers. These memory locations are defined by the MicroTech application software within the controllers, and thus compatibility between the PMF file and the MicroTech application software (IDENTs) must be maintained. Note that the BACdrop gateway is not able to check for software compatibility. It is the responsibility of the installer (typically a representative of McQuay International) to assure software compatibility using the information presented here. This edition of this BDIP documents the versions of BACdrop and MicroTech controller software as shown in the table below. If you encounter a later version of software, please refer to McQuay OnLine for an update to this document. Software Compatibility BACnet Data Information Packet Describes PMF versions Compatible IDENTs Application description BD PES2E03H Models PFS-B, water-cooled screw chiller PES2S03H PES3E03H PES3S03H PES4E03H PES4S03H FLU2E02D FLU2S02D FLU3E02D FLU3S02D FLU4E02D FLU4S02D Models WHS and PFS-C, water-cooled screw chiller 4 BD 02-8

5 Supplemental Literature For more information on the BACdrop gateway and the MicroTech control applications, see the following documents: IM 689 OM 135 MicroTech BACdrop Gateway, Installation and Maintenance Data MicroTech Water-Cooled Screw Compressor Chiller Controller, Operation Manual (WHS/PFS-C only) Conversions and Conventions Temperatures All temperatures are stated in degrees Fahrenheit ( F). To get degrees Celsius ( C), use the following: C = F Pressures All pressures are stated in pounds per square inch (psi). To get kilo-pascals (kpa), use the following: kpa = 689. psi Flow Rates All flow rates are stated in gallons per minute (gpm). To get liters per second (L/s), use the following: L/s = gpm Abbreviations BAS building automation system kpa OAT psi gpm RLA kilo-pascals outdoor air temperature pounds per square inch gallons per minute rated load amps BD

6 B-Vintage Water-Cooled Screw Chiller Analog Value Objects Instance Object_Name Property 1 UnitStatus 0 = All Systems Off 1 = Off: Alarm 2 = Off: Ambient Lockout 3 = Off: Panel Switch 4 = Off: Manual 5 = Off: Remote Switch 6 = Off: Remote Communications 7 = Off: Time Schedule 8 = Start Requested 9 = Evaporator Pump Off 10 = Evaporator Pump On: Recirculate 11 = Evaporator Pump On: Cycle Timers 12 = Evaporator Pump On: Waiting For Load 13 = Evaporator Pump On: Waiting For Flood 14 = Condenser Pump Off 15 = Condenser Pump On: Waiting For Flow 16 = Start-Up Unloading 17 = MCR Started 18 = MCR On: Prepurge 19 = MCR On: Open Solenoid 20 = Running OK 21 = MCR Off: Rapid Shutdown 22 = Shutdown Unloading Pumpdown 23 = MCR Off: Routine Shutdown 24 = Condenser Pump Off: Shutdown 25 = Evaporator Pump Off: Shutdown Prop. Description Valid Range 95 no units ChilledWaterTempActiveSpt 64 F CompressorMotorCurrent 3 Amps 0 65,535 4 CompressorSuperheatSuction 64 F 0 999* 5 CompressorSuperheatDischarge 64 F 0 999* 6 CompressorLiftPressure 56 psi 0 999* 7 CondPumpStatus 0 = Condenser Pumps Off 1 = Starting Condenser Pump #1 2 = Starting Condenser Pump #2 3 = Condenser Pump #1 On 4 = Condenser Pump #2 On 5 = Condenser Pump #1 Fail; Starting #2 6 = Condenser Pump #2 Fail; Starting #1 7 = Condenser Pumps #1 & #2 Failed 95 no units CondSatRefrigerantTemp 64 F ; = N/A 9 CondApproachTemp 64 F 0 999* 10 CondSubcoolingTemp 64 F 0 999* 11 CondWaterTempDelta 64 F 0 999* 12 CoolingTowerStage 95 no units CoolingTowerValvePosition 98 percent BD 02-8

7 Instance Object_Name Property 14 EvapPumpStatus 0 = Evaporator Pumps Off 1 = Starting Evaporator Pump #1 2 = Starting Evaporator Pump #2 3 = Evaporator Pump #1 On 4 = Evaporator Pump #2 On 5 = Evaporator Pump #1 Fail; Starting #2 6 = Evaporator Pump #2 Fail; Starting #1 7 = Evaporator Pumps #1 & #2 Failed Prop. Description Valid Range 95 no units EvapSatRefrigerantTemp 64 F ; = N/A 16 EvapApproachTemp 64 F 0 999* 17 EvapWaterTempDelta 64 F 0 999* 18 FilterPressureDrop 56 psi 0 999* 19 CompressorNumberOfStarts 95 no units 0 49, CompressorOperatingHours 71 hours 0 49, LastStartHour 95 no units LastStartMinute 95 no units LastStartMonth 95 no units LastStartDate 95 no units LastStartYear 95 no units LastStopHour 95 no units LastStopMinute 95 no units LastStopMonth 95 no units LastStopDate 95 no units LastStopYear 95 no units CondPump1OperHours 71 hours 0 49, CondPump2OperHours 71 hours 0 49, EvapPump1OperHours 71 hours 0 49, EvapPump2OperHours 71 hours 0 49, CommunicationStatus 0 = No Comm 1 = Comm. OK 95 no units 0, 1 36 ChillerUnitTempTypeConfig 0 = Standard 1 = Low Temp 37 CondWaterFlowRateSensorConfig 0 = Not Present 1 = Present 38 EvapWaterFlowRateSensorConfig 0 = Not Present 1 = Present 39 CoolingTowerControlConfig 0 = External 1 = Chiller 40 RefrigLeakDetectSensorConfig 0 = Not Present 1 = Present 41 MasterSlaveSetpointConfig 0 = Master 1 = Slave 95 no units 0, 1 95 no units 0, 1 95 no units 0, 1 95 no units 0, 1 95 no units 0, 1 95 no units 0, 1 BD

8 Instance Object_Name Property 42 LeadLagStatus 0 = Lead and lag are off 1 = Lead is on 2 = Lag is on 3 = Lead and lag are on 43 LeadUnit 0 = Master 1 = Slave 44 LeadUnitStatus Same as UnitStatus (1) 45 LagUnitStatus Same as UnitStatus (1) Prop. Description Valid Range 95 no units no units 0, 1 95 no units no units LeadMotorCurrentPct 98 percent LagMotorCurrentPct 98 percent LeadStatus 0 = Disabled 1 = Enabled 49 LagStatus 0 = Disabled 1 = Enabled 50 CurrentAlarm 0 = None 1 = Liquid Line Temp Sensor Warning 2 = Entering Evaporator Temp Sensor Warning 3 = Leaving Condenser Temp Sensor Warning 4 = Low Discharge Superheat 5 = High Discharge Superheat 6 = Entering Evaporator Temp Sensor Problem 7 = Outside Air Temp Sensor Problem 8 = High Condenser Pressure: No Load 9 = High Condenser Pressure: Unload 10 = Low Evaporator Pressure: Unload 11 = Condenser Pressure Low Freeze Protect 12 = Evaporator Pressure Low Freeze Protect 13 = Evaporator Pump 1 Fail 14 = Evaporator Pump 2 Fail 15 = Condenser Pump 1 Fail 16 = Condenser Pump 2 Fail 17 = Failed Pump Down 18 = Low Evaporator Pressure: Shutdown 19 = Low Evaporator Pressure: No Start 20 = Pre Purge Fail 21 = Open Solenoid Fail 22 = Low Motor Current 23 = High Discharge Temperature 24 = High Condenser Pressure 25 = Mechanical High Cond Pressure Switch 26 = High Motor Temperature 27 = Starter Fault 28 = No Starter Transition 29 = No Evaporator Water Flow 30 = No Condenser Water Flow 31 = Failed Stop High Motor Current 32 = No Liquid Run 33 = No Superheat Drop At Start 34 = High Discharge Superheat 35 = Evaporator Pressure Sensor Failure 36 = Entering Condenser Temp Sensor Failure 37 = Suction Temp Sensor Failure 38 = Discharge Temp Sensor Failure 39 = Condenser Pressure Sensor Failure 40 = Leaving Evap Temp Sensor Failure 41 = not used 95 no units 0, 1 95 no units 0, 1 95 no units BD 02-8

9 Instance Object_Name Property 42 = not used 43 = not used 44 = Voltage Ratio Sensor Failure 51 AtCurrAlarm_UnitStatus Same as UnitStatus (1) Prop. Description Valid Range 95 no units AtCurrAlarm_MotorCurrentPct 98 percent AtCurrAlarm_EntEvapWaterTemp 64 F ; 54 AtCurrAlarm_LvgEvapWaterTemp 64 F ; 55 AtCurrAlarm_EntCondWaterTemp 64 F ; 56 AtCurrAlarm_LvgCondWaterTemp 64 F ; 57 AtCurrAlarm_EvapPressure 56 psi 0 200; = N/A; = open; = short 58 AtCurrAlarm_CondPressure 56 psi 0 500; = N/A; = open; = short 59 AtCurrAlarm_EvapApproachTemp 64 F 0 999* 60 AtCurrAlarm_CondApproachTemp 64 F 0 999* 61 AtCurrAlarm_DischargeTemp 64 F ; 62 AtCurrAlarm_DischargeSuperheat 64 F 0 999* 63 AtCurrAlarm_SuctionSuperheat 64 F 0 999* 64 AtCurrAlarm_Subcooling 64 F 0 999* 65 AtCurrAlarm_EXVPosition 95 no units 0 760; 0 = fully closed 760 = fully open 66 AtCurrAlarm_EXVControl 0 = None 1 = Water Pressure 2 = Fuzzy Logic 95 no units AtCurrAlarm_EvapFlow 89 gpm 0 65, AtCurrAlarm_CondFlow 89 gpm 0 65, PreviousAlarm Same as CurrentAlarm (50) 95 no units 0 44 * Under normal conditions, the upper end of this object s range will be or less. If one of the sensors used to calculate the object s value is bad or disconnected, this object s value may go out of range to some arbitrary 4-digit value. ANALOG_VALUE 1: UnitStatus The overall state of the compressor controller. See IM manual for more information. BD

10 ANALOG_VALUE 2: ChilledWaterTempActiveSpt The chilled water temperature setpoint the chiller uses for temperature control. It is set by one of several control scenarios that depend on upon chiller configuration parameters. The BAS can set this setpoint by writing to the NetworkChilledWaterTempSetpoint object (ANALOG_OUTPUT 3). The resolution is 0.5 F. ANALOG_VALUE 3: CompressorMotorCurrent The compressor motor current. The actual range depends on the size of the motor. The resolution is 1 A. ANALOG_VALUE 4: CompressorSuperheatSuction The difference between the actual refrigerant temperature entering the compressor and the saturated suction temperature. The resolution is 0.1 F. ANALOG_VALUE 5: CompressorSuperheatDischarge The difference between the actual refrigerant temperature leaving the compressor and the saturated condensing temperature. The resolution is 0.1 F. ANALOG_VALUE 6: CompressorLiftPressure The pressure rise of the refrigerant as it passes through the compressor. It is calculated by subtracting the evaporator pressure from the condenser pressure. The resolution is 0.1 psi. ANALOG_VALUE 7: CondPumpStatus The operating status of the condenser water pumps. ANALOG_VALUE 8: CondSatRefrigerantTemp The saturated temperature of the refrigerant in the condenser shell. It is calculated from the measured condenser pressure. The resolution is 0.1 F. ANALOG_VALUE 9: CondApproachTemp The difference between the condenser refrigerant temperature and the condenser leaving water temperature. The resolution is 0.1 F. ANALOG_VALUE 10: CondSubcoolingTemp The subcooling temperature. It is calculated by subtracting the actual refrigerant temperature in the liquid line from the saturated condensing temperature. The resolution is 0.1 F. ANALOG_VALUE 11: CondWaterTempDelta The difference between the entering and leaving condenser water temperatures. The resolution is 0.1 F. ANALOG_VALUE 12: CoolingTowerStage The number of energized cooling tower stages. The data is valid only if tower control is provided by the chiller. ANALOG_VALUE 13: CoolingTowerValvePosition The position of the cooling tower valve. It is given as a percent of full open to the tower and has a 1% resolution. It is valid only if tower control is provided by the chiller. ANALOG_VALUE 14: EvapPumpStatus The operating status of the evaporator water pumps. ANALOG_VALUE 15: EvapSatRefrigerantTemp The temperature of the refrigerant in the evaporator shell. The resolution is 0.1 F. 10 BD 02-8

11 ANALOG_VALUE 16: EvapApproachTemp The difference between the evaporator refrigerant temperature and the leaving evaporator water temperature. The resolution is 0.1 F. ANALOG_VALUE 17: EvapWaterTempDelta The difference between the entering and leaving evaporator water temperatures. The resolution is 0.1 F. ANALOG_VALUE 18: FilterPressureDrop The pressure difference between the condenser and the liquid line. It is measured across the refrigerant filter-drier. ANALOG_VALUE 19: CompressorNumberOfStarts The total number of compressor motor starts that have occurred. The value rolls over to 0 after 49,999 starts. ANALOG_VALUE 20: CompressorOperatingHours The total number of hours the compressor has run. The value rolls over to 0 after 49,999 hours. ANALOG_VALUE 21: LastStartHour The hour the compressor last started. ANALOG_VALUE 22: LastStartMinute The minute the compressor last started. ANALOG_VALUE 23: LastStartMonth The month the compressor last started. ANALOG_VALUE 24: LastStartDate The date the compressor last started. ANALOG_VALUE 25: LastStartYear The year the compressor last started. ANALOG_VALUE 26: LastStopHour The hour the compressor last stopped. ANALOG_VALUE 27: LastStopMinute The minute the compressor last stopped. ANALOG_VALUE 28: LastStopMonth The month the compressor last stopped. ANALOG_VALUE 29: LastStopDate The date the compressor last stopped. ANALOG_VALUE 30: LastStopYear The year the compressor last stopped. ANALOG_VALUE 31: CondPump1OperHours The number of hours condenser pump #1 has run. The value rolls over to 0 after 49,999 hours. ANALOG_VALUE 32: CondPump2OperHours The number of hours condenser pump #2 has run. The value rolls over to 0 after 49,999 hours. ANALOG_VALUE 33: EvapPump1OperHours The number of hours evaporator pump #1 has run. The value rolls over to 0 after 49,999 hours. BD

12 ANALOG_VALUE 34: EvapPump2OperHours The number of hours evaporator pump #2 has run. The value rolls over to 0 after 49,999 hours. ANALOG_VALUE 35: CommunicationStatus The status of network communications with the BAS. Communications with the BAS must exist or else the chiller controller will revert to internal control setpoints. This analog value object indicates whether communications with the BAS are active. Communications are considered active when a non-zero value is periodically written to the CommunicationsSignal object (ANALOG_OUTPUT 4). See the Analog Output Objects section for more information. ANALOG_VALUE 36: ChillerUnitTempTypeConfig A configuration parameter that indicates whether the chiller is set up for standard or low discharge temperatures. ANALOG_VALUE 37: CondWaterFlowRateSensorConfig A configuration variable that indicates whether a condenser water flow rate sensor is connected to the chiller. Condenser water flow rate data (ANALOG_INPUT 4) is valid only when this sensor is present. ANALOG_VALUE 38: EvapWaterFlowRateSensorConfig A configuration variable that indicates whether an evaporator water flow rate sensor is connected to the chiller. Evaporator water flow rate data (ANALOG_INPUT 9) is valid only when this sensor is present. ANALOG_VALUE 39: CoolingTowerControlConfig A configuration variable that indicates whether cooling tower functions are being controlled by the chiller or an external control system. Cooling tower data points are valid only when the chiller is in control. ANALOG_VALUE 40: RefrigLeakDetectSensorConfig A configuration variable that indicates whether a refrigerant leak detection sensor is connected to the chiller. Refrigerant sensor data (ANALOG_INPUT 15) is valid only when this sensor is present. ANALOG_VALUE 41: MasterSlaveSetpointConfig A configuration variable that indicates whether the compressor is lead-lag Master or Slave. The Master controls lead-lag processing for the entire chiller (i.e., for both compressors), and thus certain analog output objects that control the lead-lag function should be written to only in the lead-lag Master. The MasterSlaveSetpointConfig object can be written to locally with the controller s keypad/display. A McQuay International representative should do this during the commissioning process. Note that the terms lead-lag Master and Slave refer only to the chiller s lead-lag function, not the MicroTech network architecture or communication port configurations. ANALOG_VALUE 42: LeadLagStatus This object indicates which compressors are running, in terms of their lead-lag status. ANALOG_VALUE 43: LeadUnit This object indicates which compressor is currently lead, the Master or Slave. See IM manual for more information. ANALOG_VALUE 44: LeadUnitStatus The unit status of the lead compressor. ANALOG_VALUE 45: LagUnitStatus The unit status of the lag compressor. 12 BD 02-8

13 ANALOG_VALUE 46: LeadMotorCurrentPct The current draw of the lead compressor motor as a percentage of its RLA. ANALOG_VALUE 47: LagMotorCurrentPct The current draw of the lag compressor motor as a percentage of its RLA. ANALOG_VALUE 48: LeadStatus The enabled/disabled status of the lead compressor. ANALOG_VALUE 49: LagStatus The enabled/disabled status of the lag compressor. ANALOG_VALUE 50: CurrentAlarm The current unit alarm. If multiple alarms exist at the same time, the most serious alarm (i.e., the one with the highest code number) is given. ANALOG_VALUE 51: AtCurrAlarm_UnitStatus The unit status of the chiller at the time the current alarm occurred. ANALOG_VALUE 52: AtCurrAlarm_MotorCurrentPct The motor current at which the compressor was running at the time the current alarm occurred. The resolution is 1%. ANALOG_VALUE 53: AtCurrAlarm_EntEvapWaterTemp The evaporator entering water temperature at the time the current alarm occurred. The resolution is 0.1 F. ANALOG_VALUE 54: AtCurrAlarm_LvgEvapWaterTemp The evaporator leaving water temperature at the time the current alarm occurred. The resolution is 0.1 F. ANALOG_VALUE 55: AtCurrAlarm_EntCondWaterTemp The condenser entering water temperature at the time the current alarm occurred. The resolution is 0.1 F. ANALOG_VALUE 56: AtCurrAlarm_LvgCondWaterTemp The condenser leaving water temperature at the time the current alarm occurred. The resolution is 0.1 F. ANALOG_VALUE 57: AtCurrAlarm_EvapPressure The evaporator pressure at the time the current alarm occurred. The resolution is 0.1 psi. ANALOG_VALUE 58: AtCurrAlarm_CondPressure The condenser pressure at the time the current alarm occurred. The resolution is 0.1 psi. ANALOG_VALUE 59: AtCurrAlarm_EvapApproachTemp The evaporator approach temperature at the time the current alarm occurred. The resolution is 0.1 F. ANALOG_VALUE 60: AtCurrAlarm_CondApproachTemp The condenser approach temperature at the time the current alarm occurred. The resolution is 0.1 F. ANALOG_VALUE 61: AtCurrAlarm_DischargeTemp The compressor discharge temperature at the time the current alarm occurred. The resolution is 0.1 F. ANALOG_VALUE 62: AtCurrAlarm_DischargeSuperheat The discharge superheat temperature at the time the current alarm occurred. The resolution is 0.1 F. BD

14 ANALOG_VALUE 63: AtCurrAlarm_SuctionSuperheat The suction line superheat temperature at the time the current alarm occurred. The resolution is 0.1 F. ANALOG_VALUE 64: AtCurrAlarm_Subcooling The liquid line subcooling temperature at the time the current alarm occurred. The resolution is 0.1 F. ANALOG_VALUE 65: AtCurrAlarm_EXVPosition The position of the electronic expansion valve (EXV) at the time the current alarm occurred. The value is expressed in steps. ANALOG_VALUE 66: AtCurrAlarm_EXVControl The control state of the electronic expansion valve (EXV) at the time the current alarm occurred. ANALOG_VALUE 67: AtCurrAlarm_EvapFlow The evaporator water flow rate at the time the current alarm occurred. The resolution is 1 gpm. Note that the evaporator flow rate sensor is optional. ANALOG_VALUE 68: AtCurrAlarm_CondFlow The condenser water flow rate at the time the current alarm occurred. The resolution is 1 gpm. Note that the condenser flow rate sensor is optional. ANALOG_VALUE 69: PreviousAlarm The previous alarm. In most cases, a previous alarm is a cleared alarm. An exception will occur when an active higher priority alarm replaces an active lower priority alarm. In this instance, the lower priority alarm will be pushed into the previous alarm spot even though it is still active. Analog Input Objects Instance Object_Name Property Prop. Description Valid Range 1 CompressorMotorCurrentPct 98 percent CompSuctionTemp 64 F ; 3 CondRefrigerantPressure 56 psi 0 500; = N/A; = open; = short 4 CondWaterFlowRate 89 gpm 0 65,535 5 CondWaterTempEnt 64 F ; 6 CondWaterTempLvg 64 F ; 7 DischargeRefrigerantTemp 64 F ; 8 EvapRefrigerantPressure 56 psi 0 200; = N/A; = open; = short 9 EvapWaterFlowRate 89 gpm 0 65, BD 02-8

15 Instance Object_Name Property Prop. Description Valid Range 10 EvapWaterTempEnt 64 F ; 11 EvapWaterTempLvg 64 F ; 12 LiquidLineRefrigerantTemp 64 F ; 13 LiquidLinePressure 56 psi 0 500; = N/A; = open; = short 14 OutdoorAirTemp 64 F (local), (network); 15 RefrigerantLeakConcentration 98 percent 0 100; 0 = 4 ma input; 100 = 20 ma input; 253 = N/A ANALOG_INPUT 1: CompressorMotorCurrentPct The compressor motor current as a percentage of its RLA. The resolution is 1%. ANALOG_INPUT 2: CompSuctionTemp The measured temperature of the refrigerant entering the compressor. The resolution is 0.1 F. ANALOG_INPUT 3: CondRefrigerantPressure The pressure of the refrigerant in the condenser. The resolution is 0.1 psi. ANALOG_INPUT 4: CondWaterFlowRate The rate of water flow through the condenser. The resolution is 1 gpm, and the actual range depends on the condenser flow sensor. If a sensor is present the data is always valid. ANALOG_INPUT 5: CondWaterTempEnt The temperature of the water entering the condenser. The resolution is 0.1 F. ANALOG_INPUT 6: CondWaterTempLvg The temperature of the water leaving the condenser. The resolution is 0.1 F. ANALOG_INPUT 7: DischargeRefrigerantTemp The temperature of the refrigerant as it leaves the compressor. The resolution is 0.1 F. ANALOG_INPUT 8: EvapRefrigerantPressure The pressure of the refrigerant in the evaporator. The resolution is 0.1 psi. ANALOG_INPUT 9: EvapWaterFlowRate The rate of water flow through the evaporator. The resolution is 1 gpm, and the range depends on the evaporator flow sensor. If a sensor is present the data is always valid. ANALOG_INPUT 10: EvapWaterTempEnt The temperature of the water entering the evaporator. The resolution is 0.1 F. BD

16 ANALOG_INPUT 11: EvapWaterTempLvg The temperature of the water leaving the evaporator. The resolution is 0.1 F. ANALOG_INPUT 12: LiquidLineRefrigerantTemp The measured temperature of the liquid refrigerant leaving the condenser. The resolution is 0.1 F. ANALOG_INPUT 13: LiquidLinePressure The pressure of the liquid refrigerant leaving the condenser. The resolution is 0.1 psi. ANALOG_INPUT 14: OutdoorAirTemp The outdoor air temperature. If a temperature sensor is present at the chiller and the Outdoor Air Sensor configuration parameter (available at keypad/display) is set to Local, this object will give the local value. If the Outdoor Air Sensor configuration parameter is set to Remote, this object will give the value written by the BAS. The resolution is 0.1 F. ANALOG_INPUT 15: RefrigerantLeakConcentration The concentration of refrigerant in the ambient air as measured by an optional refrigerant leak detection sensor. The value is expressed as a percentage of the sensor s full output range. For example, if a 4 20 ma sensor is calibrated to provide a 20 ma signal at an R-134a concentration of 250 ppm, a value of 50% would indicate the presence of a 125 ppm concentration of R-134a. The resolution is 1%. Analog Output Objects Instance Object_Name Property Prop. Description Valid Range 1 CapacityLimitPct 98 percent ChillerOperationMode 0 = Stop 1 = Stop (initial default) 2 = Recirculate 3 = Run 95 no units NetworkChilledWaterTempSetpoint 64 F CommunicationsSignal 0 = No Comm = Comm. 95 no units NetworkOutdoorAirTemp 64 F LeadLagModeSetpoint 0 = Master Always Lead 1 = Slave Always Lead 2 = Auto Select 95 no units EnableLagSetpoint 98 percent DisableLagSetpoint 98 percent LagStandbySetpoint 0 = No 1 = Yes 10 LeadLagSwitchSetpointDay 0 = N/A 1 = Sun 2 = Mon 3 = Tue 4 = Wed 5 = Thu 6 = Fri 7 = Sat 95 no units 0, 1 95 no units LeadLagSwitchSetpointHour 95 no units BD 02-8

17 ANALOG_OUTPUT 1: CapacityLimitPct The upper limit for cooling capacity. The normal value is 100%, which enables maximum cooling. The unit s ability to cool will be reduced by setting the limit to less than 100%. The value is a percentage of full capacity. Note: This object s value is stored in volatile memory, so after a power reset the desired value must be rewritten to the MicroTech controller. ANALOG_OUTPUT 2: ChillerOperationMode The chiller operating mode. This object is effective only when the chiller s Control Mode parameter as set at the keypad/display is Auto:Network and the CommunicationStatus object (ANALOG_VALUE 35) holds a value of 1. In the Stop mode (0), the compressor and water pumps are disabled and all valves are closed. In the Recirculate mode (2), the pumps operate and the valves open to allow water to circulate through the system, but the compressor does not start. In the Run mode (3), the pumps operate, the compressor is enabled, and the valves modulate as required. If communications with the chiller are lost (i.e., the CommunicationStatus object holds a value of 0 ), the chiller will revert to an enabled mode that acts just like the Run mode (3), regardless of the last write to the ChillerOperationMode object. The ChillerOperationMode object initializes to a default value of 1, which acts just like the Stop mode (0) when communications exist. If communications are lost, the 1 value will enable the chiller. For the purposes of a BACnet interface, it is best not to write the 1 value. When in the lead-lag configuration, the chiller operation mode must be written to both the Master and Slave units. Note: This object s value is stored in volatile memory, so after a power reset the desired value must be rewritten to the MicroTech controller. ANALOG_OUTPUT 3: NetworkChilledWaterTempSetpoint The leaving evaporator water temperature setpoint as written by the BAS. The chiller also maintains a local setpoint in non-volatile memory. This object s value will be used for chilled water temperature control (i.e., the Active Setpoint is set equal to it) when the following two conditions are true: (1) the chiller s chilled water setpoint source parameter (available at the keypad/display) is set to Network and (2) the CommunicationStatus object (ANALOG_VALUE 35) holds a value of 1. Otherwise, the chiller will use the local leaving evaporator water temperature setpoint, plus any local chilled water reset bias, for control. This setpoint should not be set below 40.0 F for standard temperature chillers, but it may be set in the 0 to 39.5 F range for low temperature units. The resolution is 0.5 F. Unlike some other MicroTech chiller controllers (e.g., reciprocating), the B-vintage water-cooled screw chiller controller will not allow the local chilled water reset methods to be used in conjunction with a base setpoint written by the BAS. If a reset scheme for the chilled water setpoint is desired, the BAS must coordinate it and write the resultant setpoint to this object. Note: This object s value is stored in volatile memory, so after a power reset the desired value must be rewritten to the MicroTech controller. ANALOG_OUTPUT 4: CommunicationsSignal A BAS-to-chiller network communications watchdog. A non-zero value should be written to this object once every 60 seconds. If the CommunicationsSignal object is not updated for five minutes, the MicroTech controller will assume there has been a loss of network communications and revert to local setpoints for unit control. BD

18 ANALOG_OUTPUT 5: NetworkOutdoorAirTemp The outdoor air temperature as written by the BAS. The resolution is 1 F. To use this object, the Outdoor Air Sensor configuration parameter (available on the keypad/display) must be set to Remote. ANALOG_OUTPUT 6: LeadLagModeSetpoint Controls the selection of the lead compressor. If Auto Select (2) is chosen, the compressor with the least run hours will become lead the next time both compressors are off. This object is effective only in the lead-lag Master. The MasterSlaveSetpointConfig object (ANALOG_VALUE 41) tells you whether the controller is Master or Slave. ANALOG_OUTPUT 7: EnableLagSetpoint If the lead compressor is running alone and its motor current (in % RLA) exceeds this value, the interstage timer begins to run. When it expires, the lag compressor turns on (unless the lag compressor has been designated as standby). The default value is 95%. This object is effective only in the lead-lag Master. The MasterSlaveSetpointConfig object (ANALOG_VALUE 41) tells you whether the controller is Master or Slave. ANALOG_OUTPUT 8: DisableLagSetpoint If both the lead and lag compressors are running and the motor current (in % RLA) of either drops below this value, the interstage timer begins to run. When it expires, the lag compressor shuts down. The default value is 40%. This object is effective only in the lead-lag Master. The MasterSlaveSetpointConfig object (ANALOG_VALUE 41) tells you whether the controller is Master or Slave. ANALOG_OUTPUT 9: LagStandbySetpoint A configuration variable that designates whether the lag compressor is to be used for standby operation only. This object is effective only in the lead-lag Master. The MasterSlaveSetpointConfig object (ANALOG_VALUE 41) tells you whether the controller is Master or Slave. ANALOG_OUTPUT 10: LeadLagSwitchSetpointDay The day on which the lead-lag Master should auto-select the lead compressor. The LeadLagModeSetpoint object (ANALOG_OUTPUT 6) must be set to Auto Select (2) to use this feature. This feature can be useful for applications in which the chiller runs continuously. This object is effective only in the lead-lag Master. The MasterSlaveSetpointConfig object (ANALOG_VALUE 41) tells you whether the controller is Master or Slave. ANALOG_OUTPUT 11: LeadLagSwitchSetpointHour The hour at which the lead-lag Master should auto-select the lead compressor. See ANALOG_OUTPUT 10 above. This object is effective only in the lead-lag Master. The MasterSlaveSetpointConfig object (ANALOG_VALUE 41) tells you whether the controller is Master or Slave. Binary Input Objects Instance Object_Name Property 1 CondWaterFlowStatus 1 = Flow 0 = No Flow 2 EvapWaterFlowStatus 1 = Flow 0 = No Flow Active_Text Property Flow Flow Inactive_Text Property No Flow No Flow 18 BD 02-8

19 BINARY_INPUT 1: CondWaterFlowStatus The state of the condenser water flow switch. BINARY_INPUT 2: EvapWaterFlowStatus The state of the evaporator water flow switch. Binary Output Objects Instance Object_Name Property 1 ClearCurrentAlarm 1 = Clear Alarm 0 = No Action Active_Text Property Clear Alarm Inactive_Text Property No Action BINARY_OUTPUT 1: ClearCurrentAlarm Clears the current active alarm. The object s value automatically changes to zero when the alarm is cleared. Note that some alarms are self-clearing. This object would need to be used only for manualclear alarms. (If a self-clearing alarm is cleared with this object, it will recur immediately since the alarm condition is still present. No harm will occur.) Note: Never command this object without investigating and correcting the cause of the alarm. BD

20 C-Vintage Water-Cooled Screw Chiller Analog Value Objects Instance Object_Name Property 1 UnitStatus 0 = Off: Alarm, Both Circ Fault 1 = Off: System Switch 2 = Off: Manual 3 = Off: Pumpdown Switches 4 = Off: Ambient Lockout 5 = Off: Remote Communications 6 = Off: Remote Switch 7 = Off: Time Schedule 8 = Off: Waiting for Flood 9 = Start Requested 10 = Evaporator Pump Off 11 = Evaporator Pump On: Waiting For Flow 12 = Evaporator Pump On: Recirculate 13 = Evaporator Pump On: Cycle Timers 14 = Evaporator Pump On: Waiting For Load 15 = Condenser Pump Off 16 = Condenser Pump On: Waiting For Flow 17 = Cool Staging 18 = Manual Cool Staging 19 = Cool Stage Up 20 = Cool Stage Down 21 = Shutdown/Pumpdown 22 = Condenser Pump Off: Shutdown 23 = Evaporator Pump Off: Shutdown Prop. Description Valid Range 95 no units StageOfCapacity 95 no units CapacityLimitingInEffect 0 = No Capacity Override 1 = High Amps 2 = Demand Limiting 3 = Max Pulldown 4 = Soft Loading 5 = High Cond Pressure: Unload 6 = Low Evap Pressure: Unload 7 = High Cond Pressure: No Load 8 = High Discharge Superheat: No Load 9 = High Discharge Superheat: Unload 4 Circuit1Status 0 = Off: Alarm 1 = Off: System Switch 2 = Off: Manual 3 = Off: Pumpdown Switch 4 = Off: Ambient Lockout 5 = Off: Remote Communications 6 = Off: Remote Switch 7 = Off: Time Schedule 8 = Off: Wait For Cycle 9 = Off: Wait For Flood 10 = Off: Ready To Start 11 = Start Requested 12 = Start-up Unloading 13 = MCR Started 14 = MCR On, Open Solenoid 15 = Running 16 = Shutdown/Pumpdown 17 = MCR Off: Rapid Shutdown 18 = MCR Off: Routine Shutdown 5 Circuit2Status Same as Circuit1Status (4) 95 no units no units no units BD 02-8

21 Instance Object_Name Property Prop. Description Valid Range 6 ChilledWaterTempActiveSpt 64 F CompSuperheatSuction_Cir1 64 F 0 999* 8 CompSuperheatSuction_Cir2 64 F 0 999* 9 CompSuperheatDischarge_Cir1 64 F 0 999* 10 CompSuperheatDischarge_Cir2 64 F 0 999* 11 CompressorLiftPressure 56 psi 0 999* 12 CondPumpStatus 0 = Condenser Pump Off 1 = Starting Condenser Pump 2 = Condenser Pump On 3 = Condenser Pump Fail 95 no units CondSatRefrigerantTemp 64 F 0 999; = N/A 14 CondApproachTemp 64 F 0 999* 15 CondSubcoolingTemp 64 F 0 999* 16 CondWaterTempDelta 64 F 0 999* 17 CoolingTowerStage 95 no units CoolingTowerValvePosition 98 percent EvapPumpStatus 0 = Evaporator Pump Off 1 = Starting Evaporator Pump 2 = Evaporator Pump On 3 = Evaporator Pump Fail 95 no units EvapSatRefrigerantTemp 64 F 0 999; = N/A 21 EvapApproachTemp 64 F 0 999* 22 EvapWaterTempDelta 64 F 0 999* 23 FilterPressureDrop 56 psi 0 999* 24 Comp1NumberOfStarts 95 no units 0 65, Comp2NumberOfStarts 95 no units 0 65, Comp1OperatingHours 71 hours 0 65, Comp2OperatingHours 71 hours 0 65, ChillerUnitTempTypeConfig 0 = Standard 1 = Low Temp 95 no units 0, 1 29 CondWaterFlowRateSensorConfig 0 = Not Present 1 = Present 30 EvapWaterFlowRateSensorConfig 0 = Not Present 1 = Present 31 CoolingTowerControlConfig 0 = External 1 = Chiller 32 RefrigLeakDetectSensorConfig 0 = Not Present 1 = Present 95 no units 0, 1 95 no units 0, 1 95 no units 0, 1 95 no units 0, 1 BD

22 Instance Object_Name Property 33 Circuit1CurrentAlarm 0 = None 1 = Liquid Line Temp Sensor Warning 2 = Entering Evap Temp Sensor Warning 3 = Leaving Cond Temp Sensor Warning 4 = Entering Evap Temp Sensor Problem 5 = Outside Air Temp Sensor Problem 6 = High Condenser Pressure: No Load 7 = High Condenser Pressure: Unload 8 = Low Evaporator Pressure: Unload 9 = Condenser Freeze Protect 10 = Evaporator Freeze Protect 11 = Low Evaporator Pressure: Shutdown 12 = Low Evaporator Pressure: No Start 13 = Low Motor Current 14 = High Discharge Line Temp 15 = High Condenser Pressure 16 = Mechanical High Cond Pressure Switch 17 = High Motor Temperature 18 = Starter Fault 19 = No Starter Transition 20 = No Evaporator Water Flow 21 = No Condenser Water Flow 22 = High Motor Current 23 = No Liquid Run 24 = No Superheat Drop At Start 25 = High Discharge Superheat 26 = Evaporator Pressure Sensor Failure 27 = Entering Cond Temp Sensor Failure 28 = Suction Temperature Sensor Failure 29 = Discharge Temperature Sensor Failure 30 = Condenser Pressure Sensor Failure 31 = Leaving Evap Temp Sensor Failure 32 = Voltage Ratio Sensor Failure 34 Circuit2CurrentAlarm Same as Circuit1CurrentAlarm (33) Prop. Description Valid Range 95 no units no units Cir1AtAlarm_EntEvapWaterTemp 64 F ; 36 Cir1AtAlarm_LvgEvapWaterTemp 64 F ; 37 Cir1AtAlarm_EntCondWaterTemp 64 F ; 38 Cir1AtAlarm_LvgCondWaterTemp 64 F ; 39 Cir1AtAlarm_EvapPressure 56 psi 0 200; = N/A; = open; = short 40 Cir1AtAlarm_CondPressure 56 psi 0 500; = N/A; = open; = short 41 Cir1AtAlarm_EvapApproachTemp 64 F 0 999* 42 Cir1AtAlarm_CondApproachTemp 64 F 0 999* 22 BD 02-8

23 Instance Object_Name Property Prop. Description Valid Range 43 Cir1AtAlarm_DischargeTemp 64 F ; 44 Cir1AtAlarm_DischargeSuperheat 64 F 0 999* 45 Cir1AtAlarm_SuctionSuperheat 64 F 0 999* 46 Cir1AtAlarm_Subcooling 64 F 0 999* 47 Cir1AtAlarm_EXVPosition 95 no units 0 760; 0 = fully closed 760 = fully open 48 Cir1AtAlarm_EvapFlow 89 gpm 0 65, Cir1AtAlarm_CondFlow 89 gpm 0 65, Cir1AtAlarm_StageCapacityPct 98 percent Cir2AtAlarm_EntEvapWaterTemp 64 F ; 52 Cir2AtAlarm_LvgEvapWaterTemp 64 F ; 53 Cir2AtAlarm_EntCondWaterTemp 64 F ; 54 Cir2AtAlarm_LvgCondWaterTemp 64 F ; 55 Cir2AtAlarm_EvapPressure 56 psi (for R22 or R134a), (for R410a); = N/A; = open; = short 56 Cir2AtAlarm_CondPressure 56 psi 0 500; = N/A; = open; = short 57 Cir2AtAlarm_EvapApproachTemp 64 F 0 999* 58 Cir2AtAlarm_CondApproachTemp 64 F 0 999* 59 Cir2AtAlarm_DischargeTemp 64 F ; 60 Cir2AtAlarm_DischargeSuperheat 64 F 0 999* 61 Cir2AtAlarm_SuctionSuperheat 64 F 0 999* 62 Cir2AtAlarm_Subcooling 64 F 0 999* 63 Cir2AtAlarm_EXVPosition 95 no units 0 760; 0 = fully closed 760 = fully open 64 Cir2AtAlarm_EvapFlow 89 gpm 0 65, Cir2AtAlarm_CondFlow 89 gpm 0 65, Cir2AtAlarm_StageCapacityPct 98 percent Circuit1PreviousAlarm Same as Circuit1CurrentAlarm (33) 95 no units Circuit2PreviousAlarm Same as Circuit1CurrentAlarm (33) 95 no units 0 32 BD

24 ANALOG_VALUE 1: UnitStatus The overall state of the chiller. See OM manual for more information. ANALOG_VALUE 2: StageOfCapacity The stage of compressor capacity at which the unit is currently operating. ANALOG_VALUE 3: CapacityLimitingInEffect The type capacity limiting that is currently preventing the chiller from staging up further or causing it to stage down at a time when the chiller would otherwise be holding steady or adding capacity in order to maintain control of the leaving evaporator water temperature. ANALOG_VALUE 4: Circuit1Status The overall state of refrigerant circuit #1. See OM manual for more information. ANALOG_VALUE 5: Circuit2Status The overall state of refrigerant circuit #2. See OM manual for more information. ANALOG_VALUE 6: ChilledWaterTempActiveSpt The Active Setpoint, which is used to control the leaving evaporator water temperature. It includes any chilled water reset that may be in effect. The resolution is 0.5 F. ANALOG_VALUE 7: CompSuperheatSuction_Cir1 The difference between the actual temperature of the refrigerant entering compressor #1 and the saturated evaporator temperature. The resolution is 0.1 F. ANALOG_VALUE 8: CompSuperheatSuction_Cir2 The difference between the actual temperature of the refrigerant entering compressor #2 and the saturated evaporator temperature. The resolution is 0.1 F. ANALOG_VALUE 9: CompSuperheatDischarge_Cir1 The difference between the actual temperature of the refrigerant leaving compressor #1 and the saturated condensing temperature. The resolution is 0.1 F. ANALOG_VALUE 10: CompSuperheatDischarge_Cir2 The difference between the actual temperature of the refrigerant leaving compressor #2 and the saturated condensing temperature. The resolution is 0.1 F. ANALOG_VALUE 11: CompressorLiftPressure The pressure rise of the refrigerant as it passes through the compressor. It is calculated by subtracting the evaporator pressure from the condenser pressure. The resolution is 0.1 psi. ANALOG_VALUE 12: CondPumpStatus The operating status of the condenser water pump. ANALOG_VALUE 13: CondSatRefrigerantTemp The saturated temperature of the refrigerant in the condenser shell. It is calculated from the measured condenser pressure. The resolution is 0.1 F. ANALOG_VALUE 14: CondApproachTemp The difference between the condenser refrigerant temperature and the condenser leaving water temperature. The resolution is 0.1 F. ANALOG_VALUE 15: CondSubcoolingTemp The subcooling temperature. It is calculated by subtracting the actual refrigerant temperature in the liquid line from the saturated condensing temperature. The resolution is 0.1 F. 24 BD 02-8

25 ANALOG_VALUE 16: CondWaterTempDelta The difference between the entering and leaving condenser water temperatures. The resolution is 0.1 F. ANALOG_VALUE 17: CoolingTowerStage The number of energized cooling tower stages. The data is valid only if tower control is provided by the chiller. ANALOG_VALUE 18: CoolingTowerValvePosition The position of the cooling tower valve. It is given as a percent of full open to the tower and has a 1% resolution. It is valid only if tower control is provided by the chiller. ANALOG_VALUE 19: EvapPumpStatus The operating status of the evaporator water pump. ANALOG_VALUE 20: EvapSatRefrigerantTemp The saturated temperature of the refrigerant in the evaporator shell. It is calculated from the measured evaporator pressure. The resolution is 0.1 F. ANALOG_VALUE 21: EvapApproachTemp The difference between the evaporator refrigerant temperature and the leaving evaporator water temperature. The resolution is 0.1 F. ANALOG_VALUE 22: EvapWaterTempDelta The difference between the entering and leaving evaporator water temperatures. The resolution is 0.1 F. ANALOG_VALUE 23: FilterPressureDrop The pressure difference between the condenser and the liquid line. It is measured across the refrigerant filter-drier. ANALOG_VALUE 24: Comp1NumberOfStarts The total number of compressor #1 motor starts that have occurred. ANALOG_VALUE 25: Comp2NumberOfStarts The total number of compressor #2 motor starts that have occurred. ANALOG_VALUE 26: Comp1OperatingHours The number of hours compressor #1 has run. The value rolls over to 0 after 65,279 hours. ANALOG_VALUE 27: Comp2OperatingHours The number of hours compressor #2 has run. The value rolls over to 0 after 65,279 hours. ANALOG_VALUE 28: ChillerUnitTempTypeConfig A configuration parameter that indicates whether the chiller is set up for standard or low discharge temperatures. ANALOG_VALUE 29: CondWaterFlowRateSensorConfig A configuration variable that indicates whether a condenser water flow rate sensor is connected to the chiller. Condenser water flow rate data (ANALOG_INPUT 6) is valid only when this sensor is present. ANALOG_VALUE 30: EvapWaterFlowRateSensorConfig A configuration variable that indicates whether an evaporator water flow rate sensor is connected to the chiller. Evaporator water flow rate data (ANALOG_INPUT 12) is valid only when this sensor is present. BD