RDY2000BN BACnet Thermostat Heat Pump Application 14901 Application Note 140-1230 2020-02-11 Smart Infrastructure
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Table of Contents Overview ................................................................................................................................... 4 BACnet ................................................................................................................................. 4 Hardware Inputs ................................................................................................................... 5 Hardware Outputs.............................................................
Overview BACnet Overview In Application 14901, the controller controls a multi-stage heat pump with a reversing valve. In addition to compressors, this heat pump may also be equipped with electric heat or a fossil fuel furnace for auxiliary heat. Secondary features include Demand Ventilation Control, Occupancy Indication, Economizer Enabling, and Humidification/Dehumidification Enabling a call for external equipment to energize. Figure 1: Hardware Diagram.
Overview Hardware Inputs Product Supported BIBBs BIBB Name DM-TS-B Device Management – Time Synchronization - B DM-RD-B Device Management - Reinitialize Device-B DM-R-B Device Management – Restart - B Hardware Inputs ● Configurable input IN1 ● Configurable input IN2 ● Configurable input IN3 ● Configurable input IN4 ● Onboard space temperature ● Onboard space humidity Configurable inputs can be configured to the following types: 1 = Indoor Temperature (Remote) 2 = Indoor Temperature (Average) 3 = S
Overview I/O Mix (Relay Assignment Matrix) I/O Mix (Relay Assignment Matrix) In a heat pump application, the maximum number of compressors is two, with up to two stages of auxiliary heat. The number of stages can be configured using the BACnet points HeatStg, CoolStg, and AuxStg. Table 2: Compressor System.
Overview I/O Mix (Relay Assignment Matrix) Compressor Heating Stages Compressor Cooling Stages Aux Heating Stages Y1 Y2 W1 W2 O/B 2 1 1 Stage 1 Compressor Heating/ Cooling Stage 2 Compressor Heating Only Aux Heat 1 N/A Reversing Valve 2 2 1 Stage 1 Compressor Heating/ Cooling Stage 2 Compressor Heating/ Cooling Aux Heat 1 N/A Reversing Valve 2 0 2 Stage 1 Compressor Heating Only Stage 2 Compressor Heating Only Aux Heat 1 Aux Heat 2 N/A 2 1 2 Stage 1 Compressor Heating/ Co
Overview Connection Diagram Connection Diagram Table 3: Heat Pump Connection Diagram C HVAC Control Circuit Common RC 24 Vac from Transformer on Cooling System RH 24 Vac from Transformer on Heating System G Fan Y1 First Stage Cooling/Heating Y2 Second Stage Cooling/Heating O/B Reversing Valve W1 First Stage Aux Heating W2 Second Stage Aux Heating OUT1 Configurable Output 1 OUT2 Configurable Output 2 OUT3 Configurable Output 3 INC Configurable Inputs 1-4 Common IN1 Configurable In
Sequence of Operation Control Temperature Setpoints Sequence of Operation The following paragraphs show the sequence of operation for Application 14901. Control Temperature Setpoints This application has a number of different room temperature setpoints (ComfortHtgSP, EconHtgSP, ComfortClgSP, and EconClgSP). The setpoint can be temporarily overridden for a period of time (default is 30 minutes). The application controls using the effective setpoint (EFF STPT).
Sequence of Operation Effective Room Temperature NOTE: Effective Setpoint does not exist as a BACnet object. The controller determines what the Effective Setpoint is by evaluating the value of ModeEff. If ModeEff is Heating, Effective Setpoint is the value of HeatingSp. If ModeEff is Cooling, Effective Setpoint is the value of CoolingSp. The actual value used by HeatingSp or CoolingSp at any given time is determined by a number of factors.
Sequence of Operation Staging Control ChgOvrDB: Change Over Deadband restricts how close CLG STPT and HTG STPT can be set. A minimum deadband (default is 5°F) must to be maintained. To separate the CLG STPT and the HTG STPT, one setpoint change may change the other setpoint to maintain a gap between them. Staging Control The heat pump is controlled by a hysteresis loop (Step Control). Hysteresis prevents the compressor/heater from frequently switching on and off.
Sequence of Operation Electric Heat (Optional) ● An Inter-stage Delay timer must be enforced between the second cooling stage OFF and the first cooling stage OFF to ensure that the first compressor will not be turned off until the second compressor has been turned off for the time set in the Inter-stage Delay. In Heating mode (and compressors are not locked out by low outdoor temperature): If HeatStg = 0, the application does not control COMPRESSOR 1.
Sequence of Operation Gas Furnace (Optional) ● If HTG STG4 is an electric heater: If IndoorTmpEff is less than the switching on point of the fourth heating stage (HeatSp – 1/2 HeatingDB – StgDifHt*3), HTG STG4 has been OFF for at least the time set in MIN OFF, and the Inter-stage Delay timer has expired, HTG STG4 is turned ON.
Sequence of Operation Operation Diagram - Heat Pump with Electrical Auxiliary Heater Operation Diagram - Heat Pump with Electrical Auxiliary Heater Figure 2: Heat Pump with Electrical Auxiliary Heater. Reversing Valve Operation The status of REV VALVE determines the operation of the heat pump’s compressors (heating or cooling). The Reversing Valve changes from heating to cooling when the following conditions have been met: ● The Reversing Valve is de-energized when the unit is in OFF mode.
Sequence of Operation Ambient Heat Pump Lockouts Figure 3: Reversing Valve Operation. Ambient Heat Pump Lockouts The Ambient Heat Pump Lockout function can determine the appropriate heating source to be enabled to optimize safety protection and heating efficiency. An outdoor temperature sensor is required to proceed with this function. The Ambient Heat Pump Lockout function is disabled if an outdoor temperature sensor is unavailable or has failed.
Sequence of Operation Ambient Heat Pump Lockouts Figure 4: Ambient Heat Pump Lockouts. ● ● ● ● If Parameter P105 (HTG FAN) FanOpr = gAS, then Parameter P206 (HP COMP LO) HPCompLock is not visible, and Parameter P207 (HP AUX LO) HpAuxLock is defined as the balance point. If the outdoor temperature is above P207, the compressor operates exclusively. If the outdoor temperature is below P207, auxiliary heat operates exclusively.
Sequence of Operation Fan Operation Figure 5: Compressor Staging with Ambient Lockout Activated. Fan Operation AUTO Mode – The fan relay is energized upon a call for heating or cooling per the operating sequence. When there is no demand for heating or cooling (none of heating/cooling stages are activated) the fan relay is de-energized. The fan will turn ON when one of the following conditions has been met: ● In Heating mode, when the compressor or stage of electric heat is ON.
Sequence of Operation Wiring Diagram Wiring Diagram CAUTION The thermostat’s digital outputs only control 24 Vac loads. The maximum rating is 1A (24 VA) for each DO. Total maximum rating for the thermostat, including all energized DOs is 4A (96 VA). Auxiliary Output 3 (OUT3) may be configured as a Dry Contact by removing jumper RC-C3 and connecting the controlled device to both terminals OUT3 and C3.
Sequence of Operation Auxiliary Sequences Figure 6: Wiring Schematic, Heat Pump. Auxiliary Sequences The RDY2000BN primary sequences are designed to control single and multi-stage heating/cooling systems to maintain a user-defined temperature setpoint.
Sequence of Operation Auxiliary Sequences ● ● If humidity rises above the setpoint (4%) before the proof timer times out, the humidification relay does not engage and the proof timer is reset. If the humidity rises to the setpoint, a 30-second proof timer engages. If the humidity is still above the setpoint after the proof timer times out, the humidification relay de-energizes.
Sequence of Operation Occupancy Notification Figure 7: Humidification and Dehumidification Operation. HmdySp: Humidification Setpoint, user-adjustable to desired level in Humidification mode. DeHmdySp: Dehumidification Setpoint, user-adjustable to desired level in Dehumidification mode. HUSP DB: A deadband is maintained between the HmdySpand the DeHmdySp. If one changes the other dynamically shifts to maintain at least a 15% gap. HU DB: Humidification/Dehumidification Deadband.
Sequence of Operation Occupancy Notification ● ● An optional occupancy sensor can be used in conjunction with the schedule. The thermostat will follow the assumptions above, but input from the occupancy sensor during a scheduled unoccupied period will put the thermostat into Occupied mode for the duration of the timer set in Parameter P404 (OCC MRT).
Sequence of Operation Air Quality Management Air Quality Management If measured CO2 exceeds the setpoint (1000 ppm) by 200 ppm after a proof timer of 60 seconds, or a CO2 concentration still exceeds the setpoint (1000 ppm) by 200 ppm, the Air Quality output relay energizes and the Fresh Air icon activates. The fan relay also energizes.
Service and Fault Messages Sensor Failure Handling Service and Fault Messages All of the three counters for the Service UV Lamp, Service Humidifier and Service Air Filter are tied to the fan running and are based on calendar days. ● Service UV Lamp (SrvcUvLamp): The UV Lamp counter keeps track of the run-time of the fan calendar days since the UV Lamp service reminder was last acknowledged/cleared.
Service and Fault Messages Overcurrent Protection Overcurrent Protection If the sum of the current flowing through all of the relays exceeds 3A, all of the relays will revert to their OFF state and the OverCurrent binary value object will turn ON. The RDY2000BN will remain in that state for four minutes. After that time, all of the relays that were placed in the OFF state will change to their ON state.
BACnet Scheduler BACnet Scheduler The thermostat’s Scheduler functionality can be manually configured using Parameter P107 (SCHEDULER) in the Wizard/Installer menu. This parameter simplifies the task of entering the local schedule using the touchscreen interface for cases where a day’s schedule may be identical to another day’s schedule. The local schedule can be disabled by setting P107 = OFF. ● By setting P107 = 1, all days will contain the same schedule.
Application 14901 Point Database Application 14901 Point Database Table 4: Point Database. Object Type1 Device Object Instance (Point Number) 4194303 Object Name (Descriptor) Factory Default| (SI Units)2 RDY 4194303 Eng Units (SI Units) State Text Enumerations/Notes AnalogInput 0 UI1.NTC10K 0.0 DegF/DegC For troubleshooting purposes only. AnalogInput 1 UI1.10V 0.0 DegF/DegC For troubleshooting purposes only. AnalogInput 2 UI2.NTC10K 0.
Application 14901 Point Database Object Type1 Object Instance (Point Number) Object Name (Descriptor) Factory Default| (SI Units)2 Eng Units (SI Units) State Text Enumerations/Notes BinaryOutput3 7 AuxOutput2 0 RelayOff/Relay On OUT2 BinaryOutput3 8 AuxOutput3 0 RelayOff/Relay On OUT3 AnalogValue 0 HmdySp 25.0 %RH If AuxOut1-3 = 1, this is a runtime humidity setpoint. AnalogValue 1 DeHmdySp 50.0 %RH If AuxOut1-3 = 2, this is a runtime dehumidification setpoint.
Application 14901 Point Database Object Type1 Object Instance (Point Number) Object Name (Descriptor) Factory Default| (SI Units)2 Eng Units (SI Units) State Text Enumerations/Notes AnalogValue 25 TmpIn3High 120.0 DegF/DegC AnalogValue 26 TmpIn4Low 0.0 DegF/DegC AnalogValue 27 TmpIn4High 120.0 DegF/DegC AnalogValue 28 InstallPW 0000.0 AnalogValue 29 ExpertPW 9999.0 AnalogValue 30 HeatingSp 70.0 DegF/DegC Effective runtime heating setpoint. AnalogValue 31 CoolingSp 75.
Application 14901 Point Database Object Type1 Object Instance (Point Number) Object Name (Descriptor) Factory Default| (SI Units)2 Eng Units (SI Units) State Text Enumerations/Notes AnalogValue 50 IndoorTmpAvg 0.0 DegF/DegC If Input1-4 = 2, this is a intermediate value. AnalogValue 51 Humidity 0.0 %RH If Input1-4 = 6, this is a runtime value. AnalogValue 52 IndoorTmpEff 0.0 DegF/DegC If Input1-4 = 1 or 2, this is a runtime value. AnalogValue 53 FanRunTime 0.
Application 14901 Point Database Object Type1 Object Instance (Point Number) Object Name (Descriptor) Factory Default| (SI Units)2 Eng Units (SI Units) State Text BinaryValue 24 HpAuxLockOn 0 No Lock/Lock BinaryValue 25 OverCurrent 0 Off/On BinaryValue 26 SchOcupy 1 No/Yes BinaryValue 27 HmiOcupy 0 No/Yes BinaryValue 28 VntlationEff 0 Off/On BinaryValue 29 PrePurgeEn 0 Off/On MultistateValue 0 Periods 1 6 Prds MultistateValue 1 TmpOvrRide 11 1F/0.
Application 14901 Point Database Object Type1 Object Instance (Point Number) Object Name (Descriptor) Factory Default| (SI Units)2 Eng Units (SI Units) State Text MultistateValue 11 TmpIn1Type 1 Type2Th, 0-10V MultistateValue 12 TmpIn2Type 1 Type2Th, 0-10V MultistateValue 13 TmpIn3Type 1 Type2Th, 0-10V MultistateValue 14 TmpIn4Type 1 Type2Th, 0-10V MultistateValue 15 StgDifCl 1 1F/0.5C, 2F/1C, 3F/1.5C, 4F/2C, 5F/2.5C, 6F/3C, 7F/3.5C, 8F/4C, 9F/4.
Application 14901 Point Database 1) Object Types are: Analog Input (AI), Analog Value (AV), Binary Input (BI), Binary Value (BV), Multistate Value (MV), and Binary Output (BO). 2) A single value in a column means that the value is the same in English units and in SI units. 3) This object has an internal algorithm commanding at Priority 16. To issue a command to the object, use a higher priority. NOTES: 1. The RDY2000BN commands its points at Priority 16. 2.
Application 14901 Point Database Object Type Object Instance (Point Number) Object Name (Descriptor) Read (R)/ Write (W) Present Value Write Values Read (R)/ Write (W) Out of Service BinaryOutput2,3 6 AuxOutput1 W (0) RelayOff; (1) Relay On W BinaryOutput2,3 7 AuxOutput2 W (0) RelayOff; (1) Relay On W BinaryOutput2,3 8 AuxOutput3 W (0) RelayOff; (1) Relay On W AnalogValue 0 HmdySp W 10 – 90% R AnalogValue 1 DeHmdySp W 10 – 90% R AnalogValue 2 CO2Setpoint W 500 – 2000
Application 14901 Point Database Object Type Object Instance (Point Number) Object Name (Descriptor) Read (R)/ Write (W) Present Value Write Values Read (R)/ Write (W) Out of Service AnalogValue 26 TmpIn4Low W -58 – 250℉; -50 – 120℃ R AnalogValue 27 TmpIn4High W -58 – 250℉; -50 – 120℃ R AnalogValue 28 InstallPW W 0000 – 4999 R AnalogValue 29 ExpertPW W 5000 – 9999 R AnalogValue 30 HeatingSp R N/A R AnalogValue 31 CoolingSp R N/A R AnalogValue 32 ComfortClgSP W
Application 14901 Point Database Object Type Object Instance (Point Number) Object Name (Descriptor) Read (R)/ Write (W) Present Value Write Values Read (R)/ Write (W) Out of Service BinaryValue 1 RevValveMode W (0) Cooling; (1) Heating R BinaryValue 2 SemiContFan W (0) No; (1) Yes R BinaryValue 3 FanOpr W (0) Gas; (1) Electric R BinaryValue 4 Eco_MstEn W (0) Disabled; (1) Enabled R BinaryValue 5 Eco_MstCtrl W (0) Disabled; (1) Enabled R BinaryValue 6 HumidityIndp W
Application 14901 Point Database Object Type Object Instance (Point Number) Object Name (Descriptor) Read (R)/ Write (W) Present Value Write Values Read (R)/ Write (W) Out of Service MultistateValue 0 Periods R N/A R MultistateValue 1 TmpOvrRide W (1) 1F/0.5C; (2) 2F/1C; (3) 3F/1.5C; (4) 4F/2C; (5) 5F/2.5C; (6) 6F/3C; (7) 7F/3.5C; (8) 8F/4C; (9) 9F/4.
Application 14901 Point Database Object Type Object Instance (Point Number) Object Name (Descriptor) Read (R)/ Write (W) Present Value Write Values Read (R)/ Write (W) Out of Service MultistateValue 15 StgDifCl W (1) 1F/0.5C; (2) 2F/1C; (3) 3F/1.5C; (4) 4F/2C; (5) 5F/2.5C; (6) 6F/3C; (7) 7F/3.5C; (8) 8F/4C; (9) 9F/4.5C; (10) 10F/5C R MultistateValue 16 CoolingDB W (1) 1F/0.5C; (2) 2F/1C; (3) 3F/1.5C; (4) 4F/2C; (5) 5F/2.5C R MultistateValue 17 StgDifHt W (1) 1F/0.
Application 14901 Point Database Table 6: Object Parameter Naming. Object Type1 Device Object Instance (Point Number) 4194303 Object Name (Descriptor) Installer Menu Parameter Number Installer Menu Parameter Name RDY AnalogInput 0 UI1.NTC10K AnalogInput 1 UI1.10V AnalogInput 2 UI2.NTC10K AnalogInput 3 UI2.10V AnalogInput 4 UI3.NTC10K AnalogInput 5 UI3.10V AnalogInput 6 UI4.NTC10K AnalogInput 7 UI4.
Application 14901 Point Database Object Type1 Object Instance (Point Number) Object Name (Descriptor) Installer Menu Parameter Number Installer Menu Parameter Name AnalogValue 5 ChgOvrDly P505 C-O DLY AnalogValue 6 MinOnTimeHt P510 M R T HT AnalogValue 7 MinOffTimeHt P509 M O T HT AnalogValue 8 MinOffTimeCl P503 M O T CL AnalogValue 9 MinOnTimeCl P504 M R T CL AnalogValue 10 OccMinRun P404 OCC MRT AnalogValue 11 StgDlyHt P507 STG DLY HT AnalogValue 12 StgDlyCl P50
Application 14901 Point Database Object Type1 Object Instance (Point Number) Object Name (Descriptor) Installer Menu Parameter Number Installer Menu Parameter Name AnalogValue 35 EconHtgSP P222 ECO HT SP AnalogValue 36 CoolStg P102 COOL STGS AnalogValue 37 PreOcpyPrg P403 PRE OC PRG AnalogValue 38 MS/TP MAC P601 MS/TP MAC AnalogValue 39 ProtClgSP P225 PROT HT SP AnalogValue 40 ProtHtgSP P224 PROT CL SP AnalogValue 41 UnitNumber P401 UNIT NMBR AnalogValue 42 HEAT LI
Application 14901 Point Database Object Type1 Object Instance (Point Number) Object Name (Descriptor) Installer Menu Parameter Number Installer Menu Parameter Name BinaryValue 11 DST P112 DAYLT SAVE BinaryValue 12 SpDispMode P113 TMP SP DIS BinaryValue 13 OcupyInput BinaryValue 14 HmdyOn BinaryValue 15 DeHmdyOn BinaryValue 16 OcupyStatus BinaryValue 17 DCV BinaryValue 18 ExtFault BinaryValue 19 EcomzrOn BinaryValue 20 SrvcUvLamp BinaryValue 21 SrvcHmdy BinaryValue
Application 14901 Point Database Object Type1 Object Instance (Point Number) Object Name (Descriptor) Installer Menu Parameter Number Installer Menu Parameter Name MultistateValue 11 TmpIn1Type P302 TMP IN 1 MultistateValue 12 TmpIn2Type P306 TMP IN 2 MultistateValue 13 TmpIn3Type P310 TMP IN 3 MultistateValue 14 TmpIn4Type P314 TMP IN 4 MultistateValue 15 StgDifCl P502 STG DIF CL MultistateValue 16 CoolingDB P506 CL DEADBND MultistateValue 17 StgDifHt P508 STG DIF HT
Scheduling Examples Scheduling Examples Table 7: Daily Schedule Example 6 Periods per Day, Parameter 107 = 1. Monday – Sunday (Each day is the same) Day Event 1 2 3 4 5 6 Mode COM ECO COM ECO COM ECO Time 6:00 AM 11:00 AM 1:00 PM 2:00 PM 3:00 PM 10:00 PM Table 8: Work Week Schedule with Weekend Example 6 Periods per Day, Parameter 107 = 2.
Scheduling Examples Table 10: Individual Days (Monday – Sunday) Example 6 Periods per Day, Parameter 107 = 7. Monday – Sunday (Each day can be unique) Day Event 1 2 3 4 5 6 Mode Comfort Economy Comfort Economy Comfort Economy Time 6:00 AM 11:00 AM 1:00 PM 2:00 PM 3:00 PM 10:00 PM NOTE: The Scheduler default setting consists of two events: Event 1 = ON (Comfort) at 7:00 AM, Event 2 = ECO (Economy) at 7:00 PM. 45 Siemens Industry, Inc.
Issued by Siemens Industry, Inc. Smart Infrastructure 1000 Deerfield Pkwy Buffalo Grove IL 60089 Tel. +1 847-215-1000 Document ID 140-1230 Edition 2020-02-11 © Siemens Industry, Inc., 2020 Technical specifications and availability subject to change without notice.
