Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints

Output setpoints for AHU control

Information

This package contains sequences generating setpoints for single zone VAV AHU control.

Package Content

Name Description
Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.CoolingCoil CoolingCoil Controller for cooling coil valve
Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.FreezeProtection FreezeProtection Freeze protection sequence for single zone air handling unit
Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ModeAndSetPoints ModeAndSetPoints Output zone setpoint with operation mode selection
Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.PlantRequests PlantRequests Output plant requests for single zone air handling unit
Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefDamper ReliefDamper Relief damper control for AHUs using actuated dampers without fan
Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefFan ReliefFan Sequence for control of relief fan in AHU
Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefFanGroup ReliefFanGroup Sequence for relief fans control for AHUs using actuated relief dampers with relief fan(s)
Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReturnFan ReturnFan Return fan control for single zone AHU
Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.Supply Supply Supply air set point for single zone VAV system
Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.Validation Validation Collection of validation models

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.CoolingCoil Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.CoolingCoil

Controller for cooling coil valve

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.CoolingCoil

Information

This block outputs the cooling coil control signal if the fan is on and the zone is in cooling status (see Buildings.Controls.OBC.ASHRAE.G36.Types.ZoneStates). Otherwise, the control signal for the coil is set to 0. The implementation is according to the Section 5.18.5.3 of ASHRAE Guideline 36, May 2020.

Parameters

TypeNameDefaultDescription
Cooling coil loop signal
SimpleControllercontrollerTypeCooCoiBuildings.Controls.OBC.CDL.T...Type of controller
RealkCooCoi0.1Gain for cooling coil control loop signal [1/K]
RealTiCooCoi900Time constant of integrator block for cooling coil control loop signal [s]
RealTdCooCoi0.1Time constant of derivative block for cooling coil control loop signal [s]

Connectors

TypeNameDescription
input RealInputTSupCooSetCooling supply air temperature setpoint [K]
input RealInputTAirSupSupply air temperature measurement [K]
input IntegerInputuZonStaZone state
input BooleanInputu1SupFanSupply fan proven on
output RealOutputyCooCoiCooling coil valve commanded position

Modelica definition

block CoolingCoil "Controller for cooling coil valve" parameter Buildings.Controls.OBC.CDL.Types.SimpleController controllerTypeCooCoi= Buildings.Controls.OBC.CDL.Types.SimpleController.PI "Type of controller"; parameter Real kCooCoi(final unit="1/K")=0.1 "Gain for cooling coil control loop signal"; parameter Real TiCooCoi(final unit="s")=900 "Time constant of integrator block for cooling coil control loop signal"; parameter Real TdCooCoi(final unit="s")=0.1 "Time constant of derivative block for cooling coil control loop signal"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TSupCooSet( final unit="K", final displayUnit="degC", final quantity="ThermodynamicTemperature") "Cooling supply air temperature setpoint"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TAirSup( final unit="K", final displayUnit="degC", final quantity="ThermodynamicTemperature") "Supply air temperature measurement"; Buildings.Controls.OBC.CDL.Interfaces.IntegerInput uZonSta "Zone state"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1SupFan "Supply fan proven on"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yCooCoi "Cooling coil valve commanded position"; Buildings.Controls.OBC.CDL.Reals.PIDWithReset conCoi( final controllerType=controllerTypeCooCoi, final k=kCooCoi, final Ti=TiCooCoi, final Td=TdCooCoi, final reverseActing=false) "Cooling coil control signal"; protected Buildings.Controls.OBC.CDL.Integers.Equal intEqu "Logical block to check if zone is in cooling state"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt( final k=Buildings.Controls.OBC.ASHRAE.G36.Types.ZoneStates.cooling) "Cooling state value"; Buildings.Controls.OBC.CDL.Reals.Switch switch "Switch to assign cooling coil control signal"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant const(k=0) "Cooling off mode"; Buildings.Controls.OBC.CDL.Logical.And and2 "Conditions for cooling state"; equation connect(const.y, switch.u3); connect(conCoi.trigger, u1SupFan); connect(conCoi.u_s, TSupCooSet); connect(conCoi.u_m, TAirSup); connect(switch.y, yCooCoi); connect(intEqu.y, and2.u1); connect(and2.u2, u1SupFan); connect(and2.y, switch.u2); connect(conInt.y, intEqu.u1); connect(uZonSta, intEqu.u2); connect(conCoi.y, switch.u1); end CoolingCoil;

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.FreezeProtection Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.FreezeProtection

Freeze protection sequence for single zone air handling unit

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.FreezeProtection

Information

Freeze protection sequence for single zone AHU system. It is developed based on Section 5.18.11 of ASHRAE Guideline 36, May 2020.

  1. If the supply air temperature TAirSup drops below 4 °C (40 °F) for 5 minutes, send two (or more, as required to ensure that heating plant is active, minHotWatReq) heating hot-water plant requests, override the outdoor air damper to the minimum position, and modulate the heating coil to maintain a suppy air temperature of at least 6 °C (42 °F). Disable this function when supply air temperature rises above 7 °C (45 °F) for 5 minutes.
  2. If the supply air temperature TAirSup drops below 3 °C (38 °F) for 5 minutes, fully close both the economizer damper and the minimum outdoor air damper for 1 hour and set a Level 3 alarm noting that minimum ventilation was interrupted. After 1 hour, the unit shall resume minimum outdoor air ventilation and enter the previous stage of freeze protection.
    • If it is warm enough that the supply air temperature rises above 7 °C (45 °F) with minimum ventilation, the unit will remain in Stage 1 freeze protection for 5 minutes then resume normal operation.
  3. Upon signal from the freeze-stat (if installed), or if supply air temperature drops below 3 °C (38 °F) for 15 minutes or below 1 °C (34 °F) for 5 minutes, shut down supply and return (or relief) fan(s), close outdoor air damper, open the cooling-coil valve to 100%, and energize the CHW pump system. Also send two (or more, as required to ensure that heating plant is active, minHotWatReq) heating hot-water plant requests, modulate the heating coil to maintain the higher of the supply air temperature or the mixed air temperature at 27 °C (80 °F), and set a Level 2 alarm indicating the unit is shut down by freeze protection.
    • If a freeze-protection shutdown is triggered by a low air temperature sensor reading, it shall remain in effect until it is reset by a software switch from the operator's workstation. (If a freeze-stat with a physical reset switch is used instead, there shall be no software reset switch.)

Parameters

TypeNameDefaultDescription
Booleanhave_freProtrueTrue: enable freeze protection
BuildingPressureControlTypesbuiPreConBuildings.Controls.OBC.ASHRA...Type of building pressure control system
FreezeStatfreStaBuildings.Controls.OBC.ASHRA...Type of freeze stat
Booleanhave_hotWatCoitrueTrue: the AHU has hot water heating coil
IntegerminHotWatReq2Minimum heating hot-water plant request to active the heating plant
Heating coil controller
SimpleControllerheaCoiConBuildings.Controls.OBC.CDL.T...Heating coil controller
Realk1Gain of coil controller [1]
RealTi0.5Time constant of integrator block [s]
RealTd0.1Time constant of derivative block [s]
RealyMax1Upper limit of output
RealyMin0Lower limit of output
Advanced
RealThys0.25Hysteresis for checking temperature difference [K]

Connectors

TypeNameDescription
input RealInputuOutDamPosMinMinimum economizer damper position limit as returned by the damper position limits sequence [1]
input RealInputuOutDamEconomizer outdoor air damper commanded position [1]
input RealInputuHeaCoiHeating coil valve commanded position [1]
input RealInputuRetDamEconomizer return air damper commanded position [1]
input RealInputTAirSupMeasured supply air temperature [K]
input BooleanInputu1FreStaFreeze protection stat signal. The stat is normally close (the input is normally true), when enabling freeze protection, the input becomes false
input BooleanInputu1SofSwiResFreeze protection reset signal from software switch
input BooleanInputu1SupFanSupply fan commanded on
input RealInputuSupFanSupply fan commanded speed [1]
input BooleanInputu1RetFanReturn fan commanded on
input RealInputuRetFanReturn fan commanded speed [1]
input BooleanInputu1RelFanRelief fan commanded on
input RealInputuRelFanRelief fan commanded speed [1]
input RealInputuCooCoiCooling coil valve commanded position [1]
input RealInputTAirMixMeasured mixed air temperature [K]
output IntegerOutputyFreProStaFreeze protection stage index
output BooleanOutputy1EneCHWPumEnergize chilled water pump
output RealOutputyRetDamReturn air damper commanded position [1]
output RealOutputyOutDamOutdoor air damper commanded position [1]
output BooleanOutputy1SupFanSupply fan commanded on
output RealOutputySupFanSupply fan commanded speed [1]
output BooleanOutputy1RetFanReturn fan commanded on
output RealOutputyRetFanReturn fan commanded speed [1]
output BooleanOutputy1RelFanRelief fan commanded on
output RealOutputyRelFanRelief fan commanded speed [1]
output RealOutputyCooCoiCooling coil valve commanded position [1]
output RealOutputyHeaCoiHeating coil valve commanded position [1]
output IntegerOutputyHotWatPlaReqRequest to heating hot-water plant
output IntegerOutputyAlaAlarm level

Modelica definition

block FreezeProtection "Freeze protection sequence for single zone air handling unit" parameter Boolean have_frePro=true "True: enable freeze protection"; parameter Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes buiPreCon=Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefDamper "Type of building pressure control system"; parameter Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat freSta=Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.No_freeze_stat "Type of freeze stat"; parameter Boolean have_hotWatCoi=true "True: the AHU has hot water heating coil"; parameter Integer minHotWatReq=2 "Minimum heating hot-water plant request to active the heating plant"; parameter Buildings.Controls.OBC.CDL.Types.SimpleController heaCoiCon= Buildings.Controls.OBC.CDL.Types.SimpleController.PI "Heating coil controller"; parameter Real k(unit="1")=1 "Gain of coil controller"; parameter Real Ti(unit="s")=0.5 "Time constant of integrator block"; parameter Real Td(unit="s")=0.1 "Time constant of derivative block"; parameter Real yMax=1 "Upper limit of output"; parameter Real yMin=0 "Lower limit of output"; parameter Real Thys(unit="K")=0.25 "Hysteresis for checking temperature difference"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uOutDamPosMin( final min=0, final max=1, final unit="1") if have_frePro "Minimum economizer damper position limit as returned by the damper position limits sequence"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uOutDam( final min=0, final max=1, final unit="1") "Economizer outdoor air damper commanded position"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uHeaCoi( final min=0, final max=1, final unit="1") if have_hotWatCoi "Heating coil valve commanded position"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uRetDam( final min=0, final max=1, final unit="1") "Economizer return air damper commanded position"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TAirSup( final unit="K", final displayUnit="degC", final quantity="ThermodynamicTemperature") if have_frePro "Measured supply air temperature"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1FreSta if freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_BAS and have_frePro "Freeze protection stat signal. The stat is normally close (the input is normally true), when enabling freeze protection, the input becomes false"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1SofSwiRes if (freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.No_freeze_stat or freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment) and have_frePro "Freeze protection reset signal from software switch"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1SupFan "Supply fan commanded on"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uSupFan( final min=0, final max=1, final unit="1") "Supply fan commanded speed"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1RetFan if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanMeasuredAir or buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanDp) "Return fan commanded on"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uRetFan( final min=0, final max=1, final unit="1") if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanMeasuredAir or buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanDp) "Return fan commanded speed"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1RelFan if buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefFan "Relief fan commanded on"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uRelFan( final min=0, final max=1, final unit="1") if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefFan) "Relief fan commanded speed"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uCooCoi( final min=0, final max=1, final unit="1") "Cooling coil valve commanded position"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TAirMix( final unit="K", final displayUnit="degC", final quantity="ThermodynamicTemperature") if have_hotWatCoi and have_frePro "Measured mixed air temperature"; Buildings.Controls.OBC.CDL.Interfaces.IntegerOutput yFreProSta "Freeze protection stage index"; Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput y1EneCHWPum if have_frePro "Energize chilled water pump"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yRetDam( final min=0, final max=1, final unit="1") "Return air damper commanded position"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yOutDam( final min=0, final max=1, final unit="1") "Outdoor air damper commanded position"; Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput y1SupFan "Supply fan commanded on"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput ySupFan( final min=0, final max=1, final unit="1") "Supply fan commanded speed"; Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput y1RetFan if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanMeasuredAir or buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanDp) "Return fan commanded on"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yRetFan( final min=0, final max=1, final unit="1") if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanMeasuredAir or buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanDp) "Return fan commanded speed"; Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput y1RelFan if buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefFan "Relief fan commanded on"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yRelFan( final min=0, final max=1, final unit="1") if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefFan) "Relief fan commanded speed"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yCooCoi( final min=0, final max=1, final unit="1") "Cooling coil valve commanded position"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yHeaCoi( final min=0, final max=1, final unit="1") if have_hotWatCoi "Heating coil valve commanded position"; Buildings.Controls.OBC.CDL.Interfaces.IntegerOutput yHotWatPlaReq if have_hotWatCoi "Request to heating hot-water plant"; Buildings.Controls.OBC.CDL.Interfaces.IntegerOutput yAla if have_frePro "Alarm level"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr( final t=273.15 + 4, final h=Thys) if have_frePro "Check if supply air temperature is less than threshold"; Buildings.Controls.OBC.CDL.Logical.Timer tim( final t=300) if have_frePro "Check if the supply air temperature has been lower than threshold value for sufficient long time"; Buildings.Controls.OBC.CDL.Integers.Switch hotWatPlaReq if have_hotWatCoi and have_frePro "Hot water plant request in stage 1 mode"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt( final k=minHotWatReq) if have_hotWatCoi and have_frePro "Minimum hot-water plant requests"; Buildings.Controls.OBC.CDL.Reals.Switch minVen if have_frePro "Minimum ventilation when in stage 1 mode"; Buildings.Controls.OBC.CDL.Reals.PID heaCoiCon1( final controllerType=heaCoiCon, final k=k, final Ti=Ti, final Td=Td, final yMax=yMax, final yMin=yMin) if have_hotWatCoi and have_frePro "Heating coil control in stage 1 mode"; Buildings.Controls.OBC.CDL.Reals.Switch heaCoi1 if have_hotWatCoi and have_frePro "Heating coil position"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr( final t=273.15 + 7, final h=Thys) if have_frePro "Check if supply air temperature is greater than threshold"; Buildings.Controls.OBC.CDL.Logical.Latch lat if have_frePro "Stay in stage 1 freeze protection mode"; Buildings.Controls.OBC.CDL.Logical.Timer tim1( final t=300) if have_frePro "Check if the supply air temperature has been lower than threshold value for sufficient long time"; Buildings.Controls.OBC.CDL.Logical.Edge endStaOne if have_frePro "Clear the latch to end the stage 1 freeze protection"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr1( final t=273.15 + 3, final h=Thys) if have_frePro "Check if supply air temperature is less than threshold"; Buildings.Controls.OBC.CDL.Logical.Timer tim2( final t=300) if have_frePro "Check if the supply air temperature has been lower than threshold value for sufficient long time"; Buildings.Controls.OBC.CDL.Logical.TrueFalseHold holSta2( final trueHoldDuration=3600, final falseHoldDuration=0) if have_frePro "Stage in stage 2 freeze protection mode"; Buildings.Controls.OBC.CDL.Reals.Switch outDam2 if have_frePro "Outdoor air damper position"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant con(final k=0.0) if have_frePro "Fully closed damper position"; Buildings.Controls.OBC.CDL.Reals.Switch retDam2 if have_frePro "Return air damper position"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant con1(final k=1.0) if have_frePro "Fully open damper or valve position"; Buildings.Controls.OBC.CDL.Integers.Switch intSwi1 if have_frePro "Alarm when it is in stage 2 mode"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt1( final k=3) if have_frePro "Level 3 alarm"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt2( final k=0) if have_hotWatCoi and have_frePro "Zero request"; Buildings.Controls.OBC.CDL.Logical.Timer tim3( final t=900) if have_frePro "Check if the supply air temperature has been lower than threshold value for sufficient long time"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr2( final t=273.15 + 1, final h=Thys) if have_frePro "Check if supply air temperature is less than threshold"; Buildings.Controls.OBC.CDL.Logical.Timer tim4( final t=300) if have_frePro "Check if the supply air temperature has been lower than threshold value for sufficient long time"; Buildings.Controls.OBC.CDL.Logical.Or3 or3 if have_frePro "Check if it should be in stage 3 mode"; Buildings.Controls.OBC.CDL.Logical.Latch lat1 if have_frePro "Stay in stage 3 freeze protection mode"; Buildings.Controls.OBC.CDL.Reals.Switch supFan if not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Supply fan speed"; Buildings.Controls.OBC.CDL.Reals.Switch retFan if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanMeasuredAir or buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanDp) and not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Return fan speed"; Buildings.Controls.OBC.CDL.Reals.Switch relFan if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefFan) and not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Relief fan speed"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant con3( final k=0) if have_frePro "Zero constant"; Buildings.Controls.OBC.CDL.Reals.Switch outDam if not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Outdoor air damper"; Buildings.Controls.OBC.CDL.Reals.Switch cooCoi if not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Cooling coil position"; Buildings.Controls.OBC.CDL.Integers.Switch hotWatPlaReq3 if have_hotWatCoi and have_frePro "Hot water plant request in stage 3 mode"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt3( final k=minHotWatReq) if have_hotWatCoi and have_frePro "Minimum hot-water plant requests"; Buildings.Controls.OBC.CDL.Reals.Max max1 if have_hotWatCoi and have_frePro "Higher of supply air and mixed air temperature"; Buildings.Controls.OBC.CDL.Reals.PID heaCoiMod( final controllerType=heaCoiCon, final k=k, final Ti=Ti, final Td=Td, final yMax=yMax, final yMin=yMin) if have_hotWatCoi and have_frePro "Heating coil control when it is in stage 3 mode"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant con4( final k=273.15 + 27) if have_hotWatCoi and have_frePro "Setpoint temperature"; Buildings.Controls.OBC.CDL.Reals.Switch heaCoiPos if have_hotWatCoi and not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Heating coil position"; Buildings.Controls.OBC.CDL.Integers.Switch intSwi3 if have_frePro "Alarm level"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt4( final k=2) if have_frePro "Level 2 alarm"; Buildings.Controls.OBC.CDL.Utilities.Assert shuDowWar( final message="Warning: the unit is shut down by freeze protection!") if have_frePro "Unit shut down warning"; Buildings.Controls.OBC.CDL.Logical.Not not1 if have_frePro "Logical not"; Buildings.Controls.OBC.CDL.Utilities.Assert disMinVenWar( final message="Warning: minimum ventilation was interrupted by freeze protection!") if have_frePro "Warning of disabling minimum ventilation "; Buildings.Controls.OBC.CDL.Logical.Not not2 if have_frePro "Logical not"; Buildings.Controls.OBC.CDL.Logical.Timer tim5( final t=3600) if have_frePro "Check if it has been in stage 2 for sufficient long time"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt5( final k=0) if have_frePro "Level 0 alarm"; Buildings.Controls.OBC.CDL.Logical.Latch lat2 if have_frePro "Stay in stage 2 freeze protection mode"; Buildings.Controls.OBC.CDL.Logical.Edge endStaTwo if have_frePro "Clear the latch to end the stage 2 freeze protection"; Buildings.Controls.OBC.CDL.Logical.Or or2 if have_frePro "Start stage 1 freeze protection mode"; Buildings.Controls.OBC.CDL.Logical.FallingEdge falEdg if have_frePro "Switch from stage 2 to stage 1"; Buildings.Controls.OBC.CDL.Reals.Switch retDam if not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Return air damper position"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant supTemSet( final k=273.15+ 6) if have_hotWatCoi and have_frePro "Supply air temperature setpoint"; Buildings.Controls.OBC.CDL.Integers.Switch intSwi2 if have_frePro "Alarm level"; Buildings.Controls.OBC.CDL.Integers.Switch intSwi4 if have_frePro "Alarm level"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt6( final k=2) if have_frePro "Stage 2 freeze protection"; Buildings.Controls.OBC.CDL.Integers.Switch intSwi5 if have_frePro "Alarm level"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt7( final k=1) if have_frePro "Stage 1 freeze protection"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt8( final k=0) if have_frePro "Stage 0 freeze protection"; Buildings.Controls.OBC.CDL.Logical.FallingEdge falEdg1 if freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_BAS and have_frePro "Reset the freeze protection by the physical reset switch in freeze stat"; Buildings.Controls.OBC.CDL.Logical.Not norFal if freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_BAS and have_frePro "The output is normally false"; Buildings.Controls.OBC.CDL.Logical.Sources.Constant con2( final k=false) if not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_BAS and have_frePro "Constant false"; Buildings.Controls.OBC.CDL.Logical.Not norSta1 if buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefFan and have_frePro "Not in stage 3"; Buildings.Controls.OBC.CDL.Logical.And and2 if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefFan) and not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Disable relief fan when in stage 3"; Buildings.Controls.OBC.CDL.Logical.And and1 if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanMeasuredAir or buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanDp) and not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Disable return fan when in stage 3"; Buildings.Controls.OBC.CDL.Logical.Not norSta2 if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanMeasuredAir or buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanDp) and have_frePro "Not in stage 3"; Buildings.Controls.OBC.CDL.Logical.Not norSta3 if have_frePro "Not in stage 3"; Buildings.Controls.OBC.CDL.Logical.And and3 if not freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Disable supply fan when in stage 3"; Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter gai4(final k=1) if freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Dummy block for enabling and disabling the conditional connection"; Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter gai1(final k=1) if freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Dummy block for enabling and disabling the conditional connection"; Buildings.Controls.OBC.CDL.Logical.Or or1 if freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment or not have_frePro "Dummy block for enabling and disabling conditional connection"; Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter gai2(final k=1) if freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Dummy block for enabling and disabling the conditional connection"; Buildings.Controls.OBC.CDL.Logical.Or or4 if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanMeasuredAir or buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanDp) and (freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment or not have_frePro) "Dummy block for enabling and disabling conditional connection"; Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter gai3(final k=1) if ( buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanMeasuredAir or buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanDp) and freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Dummy block for enabling and disabling the conditional connection"; Buildings.Controls.OBC.CDL.Logical.Or or5 if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefFan) and (freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment or not have_frePro) "Dummy block for enabling and disabling conditional connection"; Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter gai5(final k=1) if ( buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefFan) and freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Dummy block for enabling and disabling the conditional connection"; Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter gai6(final k=1) if freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment and have_frePro "Dummy block for enabling and disabling the conditional connection"; Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter gai7(final k=1) if have_hotWatCoi and (freSta == Buildings.Controls.OBC.ASHRAE.G36.Types.FreezeStat.Hardwired_to_equipment or not have_frePro) "Dummy block for enabling and disabling the conditional connection"; Buildings.Controls.OBC.CDL.Logical.Pre pre if have_frePro "Break loop"; CDL.Integers.Sources.Constant conInt9(final k=0) if not have_frePro "Dummy constant"; CDL.Integers.Sources.Constant conInt10(final k=0) if not have_frePro "Dummy constant"; CDL.Reals.MultiplyByParameter gai8(final k=1) if not have_frePro "Dummy block for enabling and disabling the conditional connection"; CDL.Reals.MultiplyByParameter gai9(final k=1) if not have_frePro "Dummy block for enabling and disabling the conditional connection"; CDL.Reals.MultiplyByParameter gai10(final k=1) if not have_frePro "Dummy block for enabling and disabling the conditional connection"; CDL.Reals.MultiplyByParameter gai11(final k=1) if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanMeasuredAir or buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReturnFanDp) and not have_frePro "Dummy block for enabling and disabling the conditional connection"; CDL.Reals.MultiplyByParameter gai12(final k=1) if (buiPreCon == Buildings.Controls.OBC.ASHRAE.G36.Types.BuildingPressureControlTypes.ReliefFan) and not have_frePro "Dummy block for enabling and disabling the conditional connection"; CDL.Reals.MultiplyByParameter gai13(final k=1) if not have_frePro "Dummy block for enabling and disabling the conditional connection"; equation connect(lesThr.y, tim.u); connect(TAirSup, lesThr.u); connect(conInt.y, hotWatPlaReq.u1); connect(uOutDamPosMin, minVen.u1); connect(supTemSet.y, heaCoiCon1.u_s); connect(TAirSup, heaCoiCon1.u_m); connect(heaCoiCon1.y, heaCoi1.u1); connect(TAirSup, greThr.u); connect(greThr.y, tim1.u); connect(tim1.passed, endStaOne.u); connect(endStaOne.y, lat.clr); connect(lat.y, hotWatPlaReq.u2); connect(lat.y, minVen.u2); connect(lat.y, heaCoi1.u2); connect(TAirSup, lesThr1.u); connect(lesThr1.y, tim2.u); connect(tim2.passed, holSta2.u); connect(con.y, outDam2.u1); connect(con1.y, retDam2.u1); connect(uRetDam, retDam2.u3); connect(conInt1.y, intSwi1.u1); connect(lesThr1.y, tim3.u); connect(TAirSup, lesThr2.u); connect(tim3.passed, or3.u1); connect(tim4.passed, or3.u2); connect(u1SofSwiRes, lat1.clr); connect(lat1.y, retFan.u2); connect(lat1.y, relFan.u2); connect(con3.y, supFan.u1); connect(con3.y, retFan.u1); connect(con3.y, relFan.u1); connect(uSupFan, supFan.u3); connect(uRetFan, retFan.u3); connect(uRelFan, relFan.u3); connect(supFan.y, ySupFan); connect(relFan.y, yRelFan); connect(retFan.y, yRetFan); connect(con3.y, outDam.u1); connect(lat1.y, outDam.u2); connect(uCooCoi, cooCoi.u3); connect(lat1.y, cooCoi.u2); connect(con1.y, cooCoi.u1); connect(conInt3.y, hotWatPlaReq3.u1); connect(lat1.y, hotWatPlaReq3.u2); connect(TAirMix, max1.u2); connect(TAirSup, max1.u1); connect(max1.y, heaCoiMod.u_m); connect(con4.y, heaCoiMod.u_s); connect(heaCoiMod.y, heaCoiPos.u1); connect(lat1.y, heaCoiPos.u2); connect(lat1.y, intSwi3.u2); connect(conInt4.y, intSwi3.u1); connect(lat1.y, not1.u); connect(not1.y, shuDowWar.u); connect(not2.y, disMinVenWar.u); connect(holSta2.y, tim5.u); connect(uOutDam, minVen.u3); connect(minVen.y, outDam2.u3); connect(outDam2.y, outDam.u3); connect(conInt2.y, hotWatPlaReq.u3); connect(conInt5.y, intSwi1.u3); connect(intSwi1.y, intSwi3.u3); connect(intSwi3.y, yAla); connect(hotWatPlaReq.y, hotWatPlaReq3.u3); connect(hotWatPlaReq3.y, yHotWatPlaReq); connect(uHeaCoi, heaCoi1.u3); connect(heaCoi1.y, heaCoiPos.u3); connect(heaCoiPos.y, yHeaCoi); connect(tim5.passed, endStaTwo.u); connect(endStaTwo.y, lat2.clr); connect(lat2.y, outDam2.u2); connect(lat2.y, not2.u); connect(lat2.y, retDam2.u2); connect(lat2.y, intSwi1.u2); connect(or2.y, lat.u); connect(falEdg.y, or2.u2); connect(lat2.y, falEdg.u); connect(lat1.y, retDam.u2); connect(con3.y, retDam.u1); connect(retDam2.y, retDam.u3); connect(retDam.y, yRetDam); connect(lat1.y, y1EneCHWPum); connect(outDam.y, yOutDam); connect(cooCoi.y, yCooCoi); connect(conInt1.y, intSwi2.u1); connect(lat1.y, intSwi2.u2); connect(lat2.y, intSwi4.u2); connect(conInt6.y, intSwi4.u1); connect(intSwi4.y, intSwi2.u3); connect(lat.y, intSwi5.u2); connect(intSwi5.y, intSwi4.u3); connect(conInt7.y, intSwi5.u1); connect(intSwi2.y, yFreProSta); connect(conInt8.y, intSwi5.u3); connect(u1FreSta, norFal.u); connect(falEdg1.y, lat1.clr); connect(con2.y, or3.u3); connect(u1RelFan, and2.u1); connect(lat1.y, norSta1.u); connect(norSta1.y, and2.u2); connect(u1RetFan, and1.u1); connect(lat1.y, norSta2.u); connect(norSta2.y, and1.u2); connect(lat1.y, norSta3.u); connect(u1SupFan, and3.u1); connect(norSta3.y, and3.u2); connect(and2.y, y1RelFan); connect(and1.y, y1RetFan); connect(and3.y, y1SupFan); connect(uRetDam, gai4.u); connect(gai4.y, yRetDam); connect(uOutDam, gai1.u); connect(gai1.y, yOutDam); connect(u1SupFan, or1.u1); connect(u1SupFan, or1.u2); connect(or1.y, y1SupFan); connect(uSupFan, gai2.u); connect(gai2.y, ySupFan); connect(u1RetFan, or4.u1); connect(u1RetFan, or4.u2); connect(or4.y, y1RetFan); connect(uRetFan, gai3.u); connect(gai3.y, yRetFan); connect(u1RelFan, or5.u1); connect(u1RelFan, or5.u2); connect(or5.y, y1RelFan); connect(uRelFan, gai5.u); connect(gai5.y, yRelFan); connect(uCooCoi, gai6.u); connect(gai6.y, yCooCoi); connect(uHeaCoi, gai7.u); connect(gai7.y, yHeaCoi); connect(lesThr2.y, tim4.u); connect(lat1.y, supFan.u2); connect(or3.y, pre.u); connect(pre.y, lat1.u); connect(holSta2.y, lat2.u); connect(tim.passed, or2.u1); connect(norFal.y, falEdg1.u); connect(norFal.y, or3.u3); connect(conInt9.y, yFreProSta); connect(conInt10.y, yHotWatPlaReq); connect(uRetDam, gai8.u); connect(gai8.y, yRetDam); connect(uOutDam, gai9.u); connect(gai9.y, yOutDam); connect(uSupFan, gai10.u); connect(gai10.y, ySupFan); connect(uRetFan, gai11.u); connect(gai11.y, yRetFan); connect(uRelFan, gai12.u); connect(gai12.y, yRelFan); connect(uCooCoi, gai13.u); connect(gai13.y, yCooCoi); end FreezeProtection;

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ModeAndSetPoints Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ModeAndSetPoints

Output zone setpoint with operation mode selection

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ModeAndSetPoints

Information

Block that outputs the zone setpoint temperature (TCooSet, THeaSet) and system operation mode (yOpeMod).

The sequence consists of the following two subsequences.

Operation mode selector

The subsequence outputs one of seven types of system operation mode (occupied, warm-up, cooldown, setback, freeze protection setback, setup, unoccupied) according to current time, the time to next occupied hours tNexOcc and current zone temperature TZon. See Buildings.Controls.OBC.ASHRAE.G36.ZoneGroups.OperationMode.

Zone setpoint temperature reset

It sets the zone temperature setpoint according to the globally specified setpoints, the local setpoint adjustments, the demand limits adjustment, the window status and the occupancy status. See Buildings.Controls.OBC.ASHRAE.G36.ThermalZones.Setpoints.

Usage

This version is for a single zone only to be used in the Single Zone VAV sequence.

Parameters

TypeNameDefaultDescription
Booleanhave_winSen Check if the zone has window status sensor
Booleanhave_occSen Check if the zone has occupancy sensor
Setpoints adjustment
Adjustable settings
Booleanhave_locAdj True: the zone has local setpoint adjustment knob
BooleansepAdj True: cooling and heating setpoint can be adjusted separately
BooleanignDemLim Flag, set to true to exempt individual zone from demand limit setpoint adjustment
Limits
RealTActCoo_max300.15Maximum active cooling setpoint [K]
RealTActCoo_min295.15Minimum active cooling setpoint [K]
RealTActHea_max295.15Maximum active heating setpoint [K]
RealTActHea_min291.15Minimum active heating setpoint [K]
RealTWinOpeCooSet322.15Cooling setpoint when window is open [K]
RealTWinOpeHeaSet277.15Heating setpoint when window is open [K]
Demand control adjustment
RealincTSetDem_10.5Cooling setpoint increase value (degC) when cooling demand limit level 1 is imposed
RealincTSetDem_21Cooling setpoint increase value (degC) when cooling demand limit level 2 is imposed
RealincTSetDem_32Cooling setpoint increase value (degC) when cooling demand limit level 3 is imposed
RealdecTSetDem_10.5Heating setpoint decrease value (degC) when heating demand limit level 1 is imposed
RealdecTSetDem_21Heating setpoint decrease value (degC) when heating demand limit level 2 is imposed
RealdecTSetDem_32Heating setpoint decrease value (degC) when heating demand limit level 3 is imposed
Advanced
RealbouLim1Threshold of temperature difference for indicating the end of setback or setup mode
RealuLow-0.1Low limit of the hysteresis for checking temperature difference
RealuHigh0.1High limit of the hysteresis for checking temperature difference
Operating mode
RealpreWarCooTim10800Maximum cool-down or warm-up time [s]
RealTZonFreProOn277.15Threshold temperature to activate the freeze protection mode [K]
RealTZonFreProOff280.15Threshold temperature to end the freeze protection mode [K]

Connectors

TypeNameDescription
input RealInputcooDowTimCool-down time retrieved from optimal cool-down block [s]
input RealInputwarUpTimWarm-up time retrieved from optimal warm-up block [s]
input BooleanInputu1WinWindow status, normally closed (true), when windows open, it becomes false
input RealInputTZonZone temperature [K]
input RealInputTOccHeaSetOccupied heating setpoint [K]
input RealInputTOccCooSetOccupied cooling setpoint [K]
input RealInputTUnoHeaSetUnoccupied heating setpoint [K]
input RealInputTUnoCooSetUnoccupied cooling setpoint [K]
input BooleanInputu1OccZone occupancy status according to the schedule: true=occupied, false=unoccupied
input RealInputtNexOccTime to next occupied period [s]
input RealInputsetAdjSetpoint adjustment value
input RealInputcooSetAdjCooling setpoint adjustment value
input RealInputheaSetAdjHeating setpoint adjustment value
input BooleanInputu1OccSenOccupancy sensor (occupied=true, unoccupied=false)
input IntegerInputuCooDemLimLevCooling demand limit level
input IntegerInputuHeaDemLimLevHeating demand limit level
output IntegerOutputyOpeModOperation mode
output RealOutputTCooSetCooling setpoint temperature [K]
output RealOutputTHeaSetHeating setpoint temperature [K]

Modelica definition

block ModeAndSetPoints "Output zone setpoint with operation mode selection" parameter Boolean have_winSen "Check if the zone has window status sensor"; parameter Boolean have_occSen "Check if the zone has occupancy sensor"; parameter Boolean have_locAdj "True: the zone has local setpoint adjustment knob"; parameter Boolean sepAdj "True: cooling and heating setpoint can be adjusted separately"; parameter Boolean ignDemLim "Flag, set to true to exempt individual zone from demand limit setpoint adjustment"; parameter Real TActCoo_max( unit="K", displayUnit="degC")=300.15 "Maximum active cooling setpoint"; parameter Real TActCoo_min( unit="K", displayUnit="degC")=295.15 "Minimum active cooling setpoint"; parameter Real TActHea_max( unit="K", displayUnit="degC")=295.15 "Maximum active heating setpoint"; parameter Real TActHea_min( unit="K", displayUnit="degC")=291.15 "Minimum active heating setpoint"; parameter Real TWinOpeCooSet( unit="K", displayUnit="degC")=322.15 "Cooling setpoint when window is open"; parameter Real TWinOpeHeaSet( unit="K", displayUnit="degC")=277.15 "Heating setpoint when window is open"; parameter Real incTSetDem_1=0.5 "Cooling setpoint increase value (degC) when cooling demand limit level 1 is imposed"; parameter Real incTSetDem_2=1 "Cooling setpoint increase value (degC) when cooling demand limit level 2 is imposed"; parameter Real incTSetDem_3=2 "Cooling setpoint increase value (degC) when cooling demand limit level 3 is imposed"; parameter Real decTSetDem_1=0.5 "Heating setpoint decrease value (degC) when heating demand limit level 1 is imposed"; parameter Real decTSetDem_2=1 "Heating setpoint decrease value (degC) when heating demand limit level 2 is imposed"; parameter Real decTSetDem_3=2 "Heating setpoint decrease value (degC) when heating demand limit level 3 is imposed"; parameter Real bouLim=1 "Threshold of temperature difference for indicating the end of setback or setup mode"; parameter Real uLow=-0.1 "Low limit of the hysteresis for checking temperature difference"; parameter Real uHigh=0.1 "High limit of the hysteresis for checking temperature difference"; parameter Real preWarCooTim(unit="s")=10800 "Maximum cool-down or warm-up time"; parameter Real TZonFreProOn( unit="K", displayUnit="degC")=277.15 "Threshold temperature to activate the freeze protection mode"; parameter Real TZonFreProOff( unit="K", displayUnit="degC")=280.15 "Threshold temperature to end the freeze protection mode"; Buildings.Controls.OBC.CDL.Interfaces.RealInput cooDowTim( final unit="s", final quantity="Time") "Cool-down time retrieved from optimal cool-down block"; Buildings.Controls.OBC.CDL.Interfaces.RealInput warUpTim( final unit="s", final quantity="Time") "Warm-up time retrieved from optimal warm-up block"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1Win if have_winSen "Window status, normally closed (true), when windows open, it becomes false"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TZon( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Zone temperature"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TOccHeaSet( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Occupied heating setpoint"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TOccCooSet( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Occupied cooling setpoint"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TUnoHeaSet( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Unoccupied heating setpoint"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TUnoCooSet( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Unoccupied cooling setpoint"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1Occ "Zone occupancy status according to the schedule: true=occupied, false=unoccupied"; Buildings.Controls.OBC.CDL.Interfaces.RealInput tNexOcc( final unit="s", final quantity="Time") "Time to next occupied period"; Buildings.Controls.OBC.CDL.Interfaces.RealInput setAdj if have_locAdj and not sepAdj "Setpoint adjustment value"; Buildings.Controls.OBC.CDL.Interfaces.RealInput cooSetAdj if have_locAdj and sepAdj "Cooling setpoint adjustment value"; Buildings.Controls.OBC.CDL.Interfaces.RealInput heaSetAdj if have_locAdj and sepAdj "Heating setpoint adjustment value"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1OccSen if have_occSen "Occupancy sensor (occupied=true, unoccupied=false)"; Buildings.Controls.OBC.CDL.Interfaces.IntegerInput uCooDemLimLev "Cooling demand limit level"; Buildings.Controls.OBC.CDL.Interfaces.IntegerInput uHeaDemLimLev "Heating demand limit level"; Buildings.Controls.OBC.CDL.Interfaces.IntegerOutput yOpeMod "Operation mode"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput TCooSet( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Cooling setpoint temperature"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput THeaSet( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Heating setpoint temperature"; Buildings.Controls.OBC.ASHRAE.G36.ZoneGroups.OperationMode opeModSel( final nZon=1, final preWarCooTim=preWarCooTim, final TZonFreProOn=TZonFreProOn, final TZonFreProOff=TZonFreProOff) "Operation mode"; Buildings.Controls.OBC.ASHRAE.G36.ThermalZones.Setpoints TZonSet( final have_occSen=have_occSen, final have_winSen=have_winSen, final have_locAdj=have_locAdj, final sepAdj=sepAdj, final ignDemLim=ignDemLim, final TActCoo_max=TActCoo_max, final TActCoo_min=TActCoo_min, final TActHea_max=TActHea_max, final TActHea_min=TActHea_min, final TWinOpeCooSet=TWinOpeCooSet, final TWinOpeHeaSet=TWinOpeHeaSet, final incTSetDem_1=incTSetDem_1, final incTSetDem_2=incTSetDem_2, final incTSetDem_3=incTSetDem_3, final decTSetDem_1=decTSetDem_1, final decTSetDem_2=decTSetDem_2, final decTSetDem_3=decTSetDem_3) "Adjust setpoint temperature"; Buildings.Controls.OBC.ASHRAE.G36.ZoneGroups.ZoneStatus zonSta( final bouLim=bouLim, final have_winSen=have_winSen, final uLow=uLow, final uHigh=uHigh) "Zone temperature status"; Buildings.Controls.OBC.CDL.Conversions.BooleanToInteger colZon "Check if the zone is cold"; Buildings.Controls.OBC.CDL.Conversions.BooleanToInteger hotZon "Check if the zone is hot"; Buildings.Controls.OBC.CDL.Logical.Sources.Constant winSta( final k=true) if not have_winSen "Assume window is closed when there is no windows status sensor"; Buildings.Controls.OBC.CDL.Logical.Sources.Constant occSta( final k=true) if not have_occSen "Assume the zone is occupied when there is no occupancy sensor"; Buildings.Controls.OBC.CDL.Conversions.BooleanToInteger booToInt "Boolean to integer"; Buildings.Controls.OBC.CDL.Logical.Not winOpe "Window is open"; equation connect(zonSta.cooDowTim, cooDowTim); connect(zonSta.warUpTim, warUpTim); connect(zonSta.u1Win, u1Win); connect(zonSta.TZon, TZon); connect(zonSta.yCooTim, opeModSel.maxCooDowTim); connect(zonSta.yWarTim, opeModSel.maxWarUpTim); connect(zonSta.yHigOccCoo, opeModSel.u1HigOccCoo); connect(zonSta.yOccHeaHig, opeModSel.u1OccHeaHig); connect(zonSta.yUnoHeaHig, colZon.u); connect(colZon.y, opeModSel.totColZon); connect(zonSta.yHigUnoCoo, hotZon.u); connect(hotZon.y, opeModSel.totHotZon); connect(zonSta.yUnoHeaHig, opeModSel.u1SetBac); connect(zonSta.yEndSetBac, opeModSel.u1EndSetBac); connect(TZon, opeModSel.TZonMin); connect(zonSta.yHigUnoCoo, opeModSel.u1SetUp); connect(zonSta.yEndSetUp, opeModSel.u1EndSetUp); connect(opeModSel.u1Occ, u1Occ); connect(opeModSel.tNexOcc, tNexOcc); connect(opeModSel.yOpeMod, TZonSet.uOpeMod); connect(TZonSet.uCooDemLimLev, uCooDemLimLev); connect(TZonSet.uHeaDemLimLev, uHeaDemLimLev); connect(opeModSel.yOpeMod, yOpeMod); connect(TZonSet.TCooSet, TCooSet); connect(TZonSet.THeaSet, THeaSet); connect(booToInt.y, opeModSel.uOpeWin); connect(TZonSet.setAdj, setAdj); connect(TZonSet.heaSetAdj, heaSetAdj); connect(u1OccSen, TZonSet.u1Occ); connect(occSta.y, TZonSet.u1Occ); connect(u1Win, TZonSet.u1Win); connect(cooSetAdj, TZonSet.cooSetAdj); connect(TOccHeaSet,zonSta.TOccHeaSet); connect(TOccCooSet,zonSta.TOccCooSet); connect(TUnoHeaSet,zonSta.TUnoHeaSet); connect(TUnoCooSet,zonSta.TUnoCooSet); connect(TOccHeaSet, TZonSet.TOccHeaSet); connect(TOccCooSet, TZonSet.TOccCooSet); connect(TUnoHeaSet, TZonSet.TUnoHeaSet); connect(TUnoCooSet, TZonSet.TUnoCooSet); connect(winSta.y, winOpe.u); connect(winOpe.y, booToInt.u); connect(u1Win, winOpe.u); end ModeAndSetPoints;

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.PlantRequests Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.PlantRequests

Output plant requests for single zone air handling unit

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.PlantRequests

Information

This sequence outputs the system reset requests for single zone air handling unit. The implementation is according to the Section 5.18.15 of ASHRAE Guideline 36, May 2020.

chilled water reset request yChiWatResReq

  1. If the supply air temperature TAirSup exceeds the cooling supply air temperature set point TSupCoo by 3 °C (5 °F) for 2 minutes, send 3 requests.
  2. If the supply air temperature TAirSup exceeds the cooling supply air temperature set point TSupCoo by 2 °C (3 °F) for 2 minutes, send 2 requests.
  3. Else if the chilled water valve position uCooCoi_actual is greater than 95%, send 1 request until the uCooCoi_actual is less than 85%.
  4. Else if the chilled water valve position uCooCoi_actual is less than 95%, send 0 request.

Chiller plant request yChiPlaReq

Send the chiller plant that serves the system a chiller plant request as follows:

  1. If the chilled water valve position uCooCoi_actual is greater than 95%, send 1 request until the uCooCoi_actual is less than 10%.
  2. Else if the chilled water valve position uCooCoi_actual is less than 95%, send 0 request.

If there is a hot-water coil (have_hotWatCoi=true), hot-water reset requests yHotWatResReq

  1. If the supply air temperature TAirSup is 17 °C (30 °F) less than the heating supply air temperature set point TSupHeaEco for 5 minutes, send 3 requests.
  2. Else if the supply air temperature TAirSup is 8 °C (15 °F) less than the heating supply air temperature set point TSupHeaEco for 5 minutes, send 2 requests.
  3. Else if the hot water valve position uHeaCoi_actual is greater than 95%, send 1 request until the uHeaCoi_actual is less than 85%.
  4. Else if the hot water valve position uHeaCoi_actual is less than 95%, send 0 request.

If there is a hot-water coil and heating hot-water plant, heating hot-water plant reqeusts yHotWatPlaReq

Send the heating hot-water plant that serves the air handling unit a heating hot-water plant request as follows:

  1. If the hot water valve position uHeaCoi_actual is greater than 95%, send 1 request until the hot water valve position is less than 10%.
  2. If the hot water valve position uHeaCoi_actual is less than 95%, send 0 requests.

Parameters

TypeNameDefaultDescription
Booleanhave_hotWatCoitrueTrue: the AHU has hot water heating coil
Advanced
RealThys0.1Hysteresis for checking temperature difference
RealposHys0.05Hysteresis for checking valve position difference

Connectors

TypeNameDescription
input RealInputTAirSupMeasured supply air temperature [K]
input RealInputTSupCooCooling supply air temperature setpoint [K]
input RealInputuCooCoi_actualCooling coil valve actual position [1]
input RealInputTSupHeaEcoHeating supply air temperature setpoint [K]
input RealInputuHeaCoi_actualHeating coil valve actual position [1]
output IntegerOutputyChiWatResReqChilled water reset request
output IntegerOutputyChiPlaReqChiller plant request
output IntegerOutputyHotWatResReqHot water reset request
output IntegerOutputyHotWatPlaReqHot water plant request

Modelica definition

block PlantRequests "Output plant requests for single zone air handling unit" parameter Boolean have_hotWatCoi = true "True: the AHU has hot water heating coil"; parameter Real Thys = 0.1 "Hysteresis for checking temperature difference"; parameter Real posHys = 0.05 "Hysteresis for checking valve position difference"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TAirSup( final unit="K", final displayUnit="degC", final quantity="ThermodynamicTemperature") "Measured supply air temperature"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TSupCoo( final unit="K", final displayUnit="degC", final quantity="ThermodynamicTemperature") "Cooling supply air temperature setpoint"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uCooCoi_actual( final unit="1", final min=0, final max=1) "Cooling coil valve actual position"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TSupHeaEco( final unit="K", final displayUnit="degC", final quantity="ThermodynamicTemperature") if have_hotWatCoi "Heating supply air temperature setpoint"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uHeaCoi_actual( final unit="1", final min=0, final max=1) if have_hotWatCoi "Heating coil valve actual position"; Buildings.Controls.OBC.CDL.Interfaces.IntegerOutput yChiWatResReq "Chilled water reset request"; Buildings.Controls.OBC.CDL.Interfaces.IntegerOutput yChiPlaReq "Chiller plant request"; Buildings.Controls.OBC.CDL.Interfaces.IntegerOutput yHotWatResReq if have_hotWatCoi "Hot water reset request"; Buildings.Controls.OBC.CDL.Interfaces.IntegerOutput yHotWatPlaReq if have_hotWatCoi "Hot water plant request"; protected Buildings.Controls.OBC.CDL.Reals.Subtract cooSupTemDif "Find the cooling supply temperature difference to the setpoint"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr( final t=3, final h=Thys) "Check if the supply temperature is greater than the setpoint by a threshold value"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr1( final t=2, final h=Thys) "Check if the supply temperature is greater than the setpoint by a threshold value"; Buildings.Controls.OBC.CDL.Logical.TrueDelay truDel( final delayTime=120) "Check if the input has been true for a certain time"; Buildings.Controls.OBC.CDL.Logical.TrueDelay truDel1( final delayTime=120) "Check if the input has been true for a certain time"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr2( final t=0.95, final h=posHys) "Check if the chilled water valve position is greater than a threshold value"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant thr( final k=3) "Constant 3"; Buildings.Controls.OBC.CDL.Integers.Switch chiWatRes3 "Send 3 chilled water reset request"; Buildings.Controls.OBC.CDL.Integers.Switch chiWatRes2 "Send 2 chilled water reset request"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant two( final k=2) "Constant 2"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr( final t=0.85, final h=posHys) "Check if the chilled water valve position is less than a threshold value"; Buildings.Controls.OBC.CDL.Logical.Latch lat "Keep true signal until other condition becomes true"; Buildings.Controls.OBC.CDL.Integers.Switch chiWatRes1 "Send 1 chilled water reset request"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant one( final k=1) "Constant 1"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant zer( final k=0) "Constant 0"; Buildings.Controls.OBC.CDL.Logical.Latch lat1 "Keep true signal until other condition becomes true"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr1( final t=0.1, final h=posHys) "Check if the chilled water valve position is less than a threshold value"; Buildings.Controls.OBC.CDL.Integers.Switch intSwi3 "Send 1 chiller plant request"; Buildings.Controls.OBC.CDL.Reals.Subtract heaSupTemDif if have_hotWatCoi "Find the heating supply temperature difference to the setpoint"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr3( final t=17, final h=Thys) if have_hotWatCoi "Check if the supply temperature is less than the setpoint by a threshold value"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr4( final t=8, final h=Thys) if have_hotWatCoi "Check if the supply temperature is less than the setpoint by a threshold value"; Buildings.Controls.OBC.CDL.Logical.TrueDelay truDel2( final delayTime=300) if have_hotWatCoi "Check if the input has been true for a certain time"; Buildings.Controls.OBC.CDL.Logical.TrueDelay truDel3( final delayTime=300) if have_hotWatCoi "Check if the input has been true for a certain time"; Buildings.Controls.OBC.CDL.Integers.Switch hotWatRes3 if have_hotWatCoi "Send 3 hot water reset request"; Buildings.Controls.OBC.CDL.Integers.Switch hotWatRes2 if have_hotWatCoi "Send 2 hot water reset request"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr2( final t=0.85, final h=posHys) if have_hotWatCoi "Check if the hot water valve position is less than a threshold value"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr5( final t=0.95, final h=posHys) if have_hotWatCoi "Check if the hot water valve position is greater than a threshold value"; Buildings.Controls.OBC.CDL.Logical.Latch lat2 if have_hotWatCoi "Keep true signal until other condition becomes true"; Buildings.Controls.OBC.CDL.Integers.Switch hotWatRes1 if have_hotWatCoi "Send 1 hot water reset request"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr3( final t=0.1, final h=posHys) if have_hotWatCoi "Check if the hot water valve position is less than a threshold value"; Buildings.Controls.OBC.CDL.Logical.Latch lat3 if have_hotWatCoi "Keep true signal until other condition becomes true"; Buildings.Controls.OBC.CDL.Integers.Switch intSwi1 if have_hotWatCoi "Send 1 hot water plant request"; equation connect(TAirSup, cooSupTemDif.u1); connect(TSupCoo, cooSupTemDif.u2); connect(cooSupTemDif.y, greThr.u); connect(greThr.y, truDel.u); connect(greThr1.y, truDel1.u); connect(cooSupTemDif.y, greThr1.u); connect(uCooCoi_actual, greThr2.u); connect(truDel.y, chiWatRes3.u2); connect(thr.y, chiWatRes3.u1); connect(truDel1.y, chiWatRes2.u2); connect(two.y, chiWatRes2.u1); connect(greThr2.y, lat.u); connect(uCooCoi_actual, lesThr.u); connect(lesThr.y, lat.clr); connect(one.y, chiWatRes1.u1); connect(lat.y, chiWatRes1.u2); connect(chiWatRes1.y, chiWatRes2.u3); connect(chiWatRes2.y, chiWatRes3.u3); connect(zer.y, chiWatRes1.u3); connect(chiWatRes3.y, yChiWatResReq); connect(greThr2.y, lat1.u); connect(uCooCoi_actual, lesThr1.u); connect(lesThr1.y, lat1.clr); connect(lat1.y, intSwi3.u2); connect(one.y, intSwi3.u1); connect(zer.y, intSwi3.u3); connect(intSwi3.y, yChiPlaReq); connect(TAirSup, heaSupTemDif.u2); connect(greThr3.y, truDel2.u); connect(greThr4.y, truDel3.u); connect(heaSupTemDif.y, greThr3.u); connect(heaSupTemDif.y, greThr4.u); connect(truDel2.y, hotWatRes3.u2); connect(thr.y, hotWatRes3.u1); connect(hotWatRes2.y, hotWatRes3.u3); connect(two.y, hotWatRes2.u1); connect(truDel3.y, hotWatRes2.u2); connect(hotWatRes3.y, yHotWatResReq); connect(uHeaCoi_actual, greThr5.u); connect(greThr5.y, lat2.u); connect(uHeaCoi_actual, lesThr2.u); connect(lesThr2.y, lat2.clr); connect(lat2.y, hotWatRes1.u2); connect(one.y, hotWatRes1.u1); connect(zer.y, hotWatRes1.u3); connect(hotWatRes1.y, hotWatRes2.u3); connect(uHeaCoi_actual, lesThr3.u); connect(lesThr3.y, lat3.clr); connect(greThr5.y, lat3.u); connect(lat3.y, intSwi1.u2); connect(one.y, intSwi1.u1); connect(zer.y, intSwi1.u3); connect(intSwi1.y, yHotWatPlaReq); connect(TSupHeaEco, heaSupTemDif.u1); end PlantRequests;

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefDamper Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefDamper

Relief damper control for AHUs using actuated dampers without fan

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefDamper

Information

Sequence for controlling actuated relief damper yRelDam for AHUs using actuated relief damper without a fan. It is implemented according to Section 5.18.8 of ASHRAE Guideline G36, May 2020.

In Section 3.2.2.3, find the relief damper position setpoint limits:

Relief damper shall be enabled when the associated supply fan is proven on and any outdoor air damper is open, and disabled and closed otherwise.

Relief damper position shall be reset lineary from relDam_min to relDam_max as the commanded economizer damper position goes from uOutDam_min to 100% open.

Image of the relief damper control chart for single zone AHU

Parameters

TypeNameDefaultDescription
RealrelDam_min Relief-damper position that maintains a building pressure of 12 Pa while the economizer damper is positioned to provide minimum outdoor air while the supply fan is at minimum speed
RealrelDam_max Relief-damper position that maintains a building pressure of 12 Pa while the economizer damper is fully open and the fan speed is at cooling maximum
Advanced
RealposHys0.05Hysteresis for damper position check

Connectors

TypeNameDescription
input RealInputuOutDam_minOutdoor air damper minimum position [1]
input RealInputuOutDamOutdoor damper position [1]
input BooleanInputu1SupFanSupply fan command on
output RealOutputyRelDamRelief damper commanded position [1]

Modelica definition

block ReliefDamper "Relief damper control for AHUs using actuated dampers without fan" parameter Real relDam_min "Relief-damper position that maintains a building pressure of 12 Pa while the economizer damper is positioned to provide minimum outdoor air while the supply fan is at minimum speed"; parameter Real relDam_max "Relief-damper position that maintains a building pressure of 12 Pa while the economizer damper is fully open and the fan speed is at cooling maximum"; parameter Real posHys=0.05 "Hysteresis for damper position check"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uOutDam_min( final min=0, final max=1, final unit="1") "Outdoor air damper minimum position"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uOutDam( final min=0, final max=1, final unit="1") "Outdoor damper position"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1SupFan "Supply fan command on"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yRelDam( final unit="1", final min=0, final max=1) "Relief damper commanded position"; protected Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr( final t=0.05, final h=posHys) "Check if the outdoor damper is open"; Buildings.Controls.OBC.CDL.Logical.And and2 "Check if the relief damper should be open"; Buildings.Controls.OBC.CDL.Reals.Switch swi "Check if relief damper should be enabled"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant zerDam( final k=0) "Close damper when disabled"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant minRel( final k=relDam_min) "Minimum relief damper position"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant maxRel( final k=relDam_max) "Maximum relief damper position"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant fulOpe( final k=1) "Fully open relief damper"; Buildings.Controls.OBC.CDL.Reals.Line relDam( final limitBelow=true, final limitAbove=true) "Relief damper signal is linearly proportional to the control signal between signal limits"; equation connect(zerDam.y, swi.u3); connect(swi.y, yRelDam); connect(greThr.y, and2.u1); connect(u1SupFan, and2.u2); connect(and2.y, swi.u2); connect(uOutDam, relDam.u); connect(uOutDam_min, relDam.x1); connect(minRel.y, relDam.f1); connect(relDam.y, swi.u1); connect(uOutDam, greThr.u); connect(fulOpe.y, relDam.x2); connect(maxRel.y, relDam.f2); end ReliefDamper;

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefFan Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefFan

Sequence for control of relief fan in AHU

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefFan

Information

Sequence for controling relief fan that is part of AHU. It is developed based on Section 5.16.9 of ASHRAE Guideline 36, May 2020, with the modification to accommodate the single relief fan control.

  1. The relief fan shall be enabled when the AHU supply fan is proven ON (u1SupFan=true), and shall be disabled otherwise.
  2. Building static pressure (dpBui) shall be time averaged with a sliding 5-minute window and 15 second sampling rate (to dampen fluctuations). The average value shall be that displayed and used for control.
  3. A P-only control loop maintains the building pressure at a set point (dpBuiSet) of 12 Pa (0.05 in. of water) with an output ranging from 0% to 100%. The loop is disabled and output set to zero when the relief fan is disabled.
  4. Fan speed shall be equal to the PID signal but no less than the minimum speed.
    1. When relief system is enabled, and the control loop output is above 5%, open the motorized dampers to the relief fans; close the dampers when the loop output drops to 0% for 5 minutes.
    2. When the control loop output is above minimum speed (relFanSpe_min) plus 15% by 7 minutes, start the relief fan.
    3. When the control loop output is below minimum speed (relFanSpe_min) by 5 minutes, shut off the relief fan.

Parameters

TypeNameDefaultDescription
RealrelFanSpe_min0.1Relief fan minimum speed
RealdpBuiSet12Building static pressure difference relative to ambient (positive to pressurize the building) [Pa]
Pressure controller
Realk1Gain, normalized using dpBuiSet [1]
Advanced
Realhys0.005Hysteresis for checking the controller output value

Connectors

TypeNameDescription
input RealInputdpBuiBuilding static pressure difference, relative to ambient (positive if pressurized) [Pa]
input BooleanInputu1SupFanAHU supply fan proven on status
output RealOutputyDpBuiBuilding static pressure difference, relative to ambient (positive if pressurized) [Pa]
output RealOutputyDamDamper commanded position [1]
output RealOutputyRelFanRelief fan commanded speed [1]
output BooleanOutputy1RelFanRelief fan commanded on

Modelica definition

block ReliefFan "Sequence for control of relief fan in AHU" parameter Real relFanSpe_min( final min=0, final max=1)= 0.1 "Relief fan minimum speed"; parameter Real dpBuiSet( final unit="Pa", final quantity="PressureDifference", final max=30) = 12 "Building static pressure difference relative to ambient (positive to pressurize the building)"; parameter Real k( final unit="1") = 1 "Gain, normalized using dpBuiSet"; parameter Real hys = 0.005 "Hysteresis for checking the controller output value"; Buildings.Controls.OBC.CDL.Interfaces.RealInput dpBui( unit="Pa", displayUnit="Pa", final quantity="PressureDifference") "Building static pressure difference, relative to ambient (positive if pressurized)"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1SupFan "AHU supply fan proven on status"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yDpBui( unit="Pa", displayUnit="Pa", final quantity="PressureDifference") "Building static pressure difference, relative to ambient (positive if pressurized)"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yDam( final unit="1", final min=0, final max=1) "Damper commanded position"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yRelFan( final unit="1", final max=1) "Relief fan commanded speed"; Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput y1RelFan "Relief fan commanded on"; Buildings.Controls.OBC.CDL.Reals.MovingAverage movMea( final delta=300) "Average building static pressure measurement"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant dpBuiSetPoi( final k=dpBuiSet) "Building pressure setpoint"; Buildings.Controls.OBC.CDL.Reals.Divide div1 "Normalized the control error"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant conOne( final k=1) "Constant one"; Buildings.Controls.OBC.CDL.Reals.PID conP( final controllerType=Buildings.Controls.OBC.CDL.Types.SimpleController.P, final k=k, final reverseActing=false) "Building static pressure controller"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr( final t=0.05, final h=hys) "Check if the controller output is greater than threshold"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr( final t=0.005, final h=hys) "Check if the controller output is near zero"; Buildings.Controls.OBC.CDL.Logical.Timer tim( final t=300) "Check if the controller output has been near zero for threshold time"; Buildings.Controls.OBC.CDL.Logical.And and2 "Check if the controller output is greater than threshold and the relief system has been enabled"; Buildings.Controls.OBC.CDL.Logical.Latch lat "Enable damper"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr2( final t=relFanSpe_min + 0.15, final h=hys) "Check if the controller output is greater than minimum speed plus threshold"; Buildings.Controls.OBC.CDL.Logical.Timer upTim( final t=420) "Check if the controller output has been greater than threshold for sufficient long time"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr3( final t=relFanSpe_min, final h=hys) "Check if the controller output is less than minimum speed"; Buildings.Controls.OBC.CDL.Logical.Timer dowTim( final t=300) "Check if the controller output has been less than threshold for sufficient long time"; Buildings.Controls.OBC.CDL.Logical.Latch lat1 "Stage down lag fan"; Buildings.Controls.OBC.CDL.Logical.Or relDam "Open relief damper"; Buildings.Controls.OBC.CDL.Logical.And relFan "Turn on relief fan"; Buildings.Controls.OBC.CDL.Conversions.BooleanToReal booToRea2 "Convert boolean to real"; Buildings.Controls.OBC.CDL.Reals.Multiply pro1 "Relief fan speed"; Buildings.Controls.OBC.CDL.Conversions.BooleanToReal booToRea1 "Convert boolean to real"; equation connect(dpBui, movMea.u); connect(dpBuiSetPoi.y, div1.u2); connect(movMea.y, div1.u1); connect(div1.y, conP.u_m); connect(conOne.y, conP.u_s); connect(conP.y, greThr.u); connect(greThr.y, and2.u1); connect(conP.y, lesThr.u); connect(lesThr.y, tim.u); connect(tim.passed, lat.clr); connect(and2.y, lat.u); connect(u1SupFan, and2.u2); connect(conP.y, greThr2.u); connect(greThr2.y, upTim.u); connect(conP.y, lesThr3.u); connect(lesThr3.y, dowTim.u); connect(upTim.passed, lat1.u); connect(dowTim.passed, lat1.clr); connect(lat.y, relDam.u1); connect(u1SupFan, relFan.u1); connect(lat1.y, relFan.u2); connect(relFan.y, relDam.u2); connect(relFan.y, booToRea2.u); connect(booToRea2.y, pro1.u2); connect(conP.y, pro1.u1); connect(movMea.y, yDpBui); connect(relDam.y, booToRea1.u); connect(booToRea1.y, yDam); connect(pro1.y, yRelFan); connect(relFan.y, y1RelFan); end ReliefFan;

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefFanGroup Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefFanGroup

Sequence for relief fans control for AHUs using actuated relief dampers with relief fan(s)

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReliefFanGroup

Information

Sequence for controlling relief fans and their dampers for AHUs using actuated relief dampers with relief fan(s). It is developed based on Section 5.16.9 of ASHRAE Guideline 36, May 2020.

  1. All operating relief fans that serve a common or shared air volume shall be grouped and controlled as if they were one system, running at the same speed and using the same control loop, even if they are associated with different AHUs.
  2. A relief fan shall be enabled when its associated supply fan is proven ON (u1SupFan=true), and shall be disabled otherwise.
  3. Building static pressure (dpBui) shall be time averaged with a sliding 5-minute window and 15 second sampling rate (to dampen fluctuations). The average value shall be that displayed and used for control.
  4. A P-only control loop maintains the building pressure at a set point (dpBuiSet) of 12 Pa (0.05 in. of water) with an output ranging from 0% to 100%. The loop is disabled and output set to zero when all fans in the relief system group are disabled.
  5. Fan speed signal to all operating fans in the relief system group shall be the same and shall be equal to the PID signal but no less than the minimum speed. Except for Stage 0, discharge dampers of all relief fans shall be open only when fan is commanded ON.
    1. Stage 0 (barometric relief). When relief system is enabled, and the control loop output is above 5%, open the motorized dampers to all relief fans serving the relief system group that are enabled; close the dampers when the loop output drops to 0% for 5 minutes.
    2. Stage Up. When control loop is above minimum speed (relFanSpe_min) plus 15%, start stage-up timer. Each time the timer reaches 7 minutes, start the next relief fan (and open the associated damper) in the relief system group, per staging order, and reset the timer to 0. The timer is reset to 0 and frozen if control loop is below minimum speed plus 15%. Note, when staging from Stage 0 (no relief fans) to Stage 1 (one relief fan), the discharge dampers of all nonoperating relief fans must be closed.
    3. Stage Down. When PID loop is below minimum speed (relFanSpe_min), start stage-down timer. Each time the timer reaches 5 minutes, shut off lag fan per staging order and reset the timer to 0. The timer is reset to 0 and frozen if PID loop rises above minimum speed or all fans are OFF. If all fans are OFF, go to Stage 0 (all dampers open and all fans OFF).
  6. For fans in a Level 2 alarm and status is OFF, discharge damper shall be closed when is above Stage 0.

Parameters

TypeNameDefaultDescription
IntegernSupFan2Total number of AHU supply fans that are serving the same common space
IntegernRelFan4Total number of relief fans that are serving the same common space
RealrelFanSpe_min0.1Relief fan minimum speed
IntegerstaVec[nRelFan]{2,3,1,4}Vector of the order for staging up relief fan, i.e. the 1st element means the 1st relief fan and its value showing its sequence when staging up
IntegerrelFanMat[nRelFan, nSupFan]{{1,0},{1,0},{0,1},{0,1}}Relief fan matrix with relief fan as row index and AHU supply fan as column index. It flags which relief fan is associated with which supply fan
RealdpBuiSet12Building static pressure difference relative to ambient (positive to pressurize the building) [Pa]
Pressure controller
Realk1Gain, normalized using dpBuiSet [1]
Advanced
Realhys0.005Hysteresis for checking the controller output value

Connectors

TypeNameDescription
input BooleanInputu1SupFan[nSupFan]AHU supply fan proven on status
input RealInputdpBuiBuilding static pressure difference, relative to ambient (positive if pressurized) [Pa]
input IntegerInputuRelFanAla[nRelFan]Relief fan current alarm index
input BooleanInputu1RelFan[nRelFan]Relief fan proven on status
output RealOutputyDpBuiBuilding static pressure difference, relative to ambient (positive if pressurized) [Pa]
output RealOutputyRelFan[nRelFan]Relief fan commanded speed [1]
output RealOutputyDam[nRelFan]Relief damper commanded position [1]

Modelica definition

block ReliefFanGroup "Sequence for relief fans control for AHUs using actuated relief dampers with relief fan(s)" parameter Integer nSupFan = 2 "Total number of AHU supply fans that are serving the same common space"; parameter Integer nRelFan = 4 "Total number of relief fans that are serving the same common space"; parameter Real relFanSpe_min( final min=0, final max=1)= 0.1 "Relief fan minimum speed"; parameter Integer staVec[nRelFan] = {2,3,1,4} "Vector of the order for staging up relief fan, i.e. the 1st element means the 1st relief fan and its value showing its sequence when staging up"; parameter Integer relFanMat[nRelFan, nSupFan] = {{1,0},{1,0},{0,1},{0,1}} "Relief fan matrix with relief fan as row index and AHU supply fan as column index. It flags which relief fan is associated with which supply fan"; parameter Real dpBuiSet( final unit="Pa", final quantity="PressureDifference", final max=30) = 12 "Building static pressure difference relative to ambient (positive to pressurize the building)"; parameter Real k( final unit="1") = 1 "Gain, normalized using dpBuiSet"; parameter Real hys = 0.005 "Hysteresis for checking the controller output value"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1SupFan[nSupFan] "AHU supply fan proven on status"; Buildings.Controls.OBC.CDL.Interfaces.RealInput dpBui( unit="Pa", displayUnit="Pa", final quantity="PressureDifference") "Building static pressure difference, relative to ambient (positive if pressurized)"; Buildings.Controls.OBC.CDL.Interfaces.IntegerInput uRelFanAla[nRelFan] "Relief fan current alarm index"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1RelFan[nRelFan] "Relief fan proven on status"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yDpBui( unit="Pa", displayUnit="Pa", final quantity="PressureDifference") "Building static pressure difference, relative to ambient (positive if pressurized)"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yRelFan[nRelFan]( final unit=fill("1", nRelFan), final max=fill(1, nRelFan)) "Relief fan commanded speed"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yDam[nRelFan]( final unit=fill("1",nRelFan), final min=fill(0,nRelFan), final max=fill(1,nRelFan)) "Relief damper commanded position"; Buildings.Controls.OBC.CDL.Reals.MatrixGain enaRel( final K=relFanMat) "Vector of relief fans with the enabled one denoted by 1"; Buildings.Controls.OBC.CDL.Conversions.BooleanToReal booToRea[nSupFan] "Convert boolean to real"; Buildings.Controls.OBC.CDL.Reals.MultiplyByParameter gai[nRelFan]( final k=staVec) "Vector of enabling fan, along with its staging order"; Buildings.Controls.OBC.CDL.Reals.MovingAverage movMea( final delta=300) "Average building static pressure measurement"; Buildings.Controls.OBC.CDL.Reals.Divide div1 "Normalized the control error"; Buildings.Controls.OBC.CDL.Reals.PID conP( final controllerType=Buildings.Controls.OBC.CDL.Types.SimpleController.P, final k=k, final reverseActing=false) "Building static pressure controller"; Buildings.Controls.OBC.CDL.Logical.MultiOr enaRelGro( final nin=nSupFan) "Relief group enabling status"; Buildings.Controls.OBC.CDL.Conversions.BooleanToReal booToRea1 "Convert boolean to real"; Buildings.Controls.OBC.CDL.Reals.Multiply pro "Set controller output to zero when the relief system is disabled"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr( final t=0.05, final h=hys) "Check if the controller output is greater than threshold"; Buildings.Controls.OBC.CDL.Logical.And and2 "Check if the controller output is greater than threshold and the relief system has been enabled"; Buildings.Controls.OBC.CDL.Logical.Latch lat "Enable damper"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr( final t=0.005, final h=hys) "Check if the controller output is near zero"; Buildings.Controls.OBC.CDL.Logical.Timer tim( final t=300) "Check if the controller output has been near zero for threshold time"; Buildings.Controls.OBC.CDL.Routing.BooleanScalarReplicator booRep( final nout=nRelFan) "Boolean replicator"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr1[nRelFan]( final t=fill(0.5, nRelFan)) "Check if a relief fan should be enabled"; Buildings.Controls.OBC.CDL.Logical.And enaDam[nRelFan] "Enable damper"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr2( final t=relFanSpe_min + 0.15, final h=hys) "Check if the controller output is greater than minimum speed plus threshold"; Buildings.Controls.OBC.CDL.Logical.Timer upTim( final t=420) "Check if the controller output has been greater than threshold for sufficient long time"; Buildings.Controls.OBC.CDL.Logical.Pre pre( final pre_u_start=true) "Break algebraic loop"; Buildings.Controls.OBC.CDL.Conversions.BooleanToReal booToRea2[nRelFan] "Convert boolean to real"; Buildings.Controls.OBC.CDL.Reals.Subtract sub2[nRelFan] "Identify relief fans that have been enabled but not yet operating"; Buildings.Controls.OBC.CDL.Reals.Multiply pro1[nRelFan] "List of standby fans, along with their staging order"; Buildings.Controls.OBC.CDL.Reals.MultiMin mulMin(nin=nRelFan) "Identify current order of staging"; Buildings.Controls.OBC.CDL.Routing.RealScalarReplicator reaRep( final nout=nRelFan) "Replicate real number"; Buildings.Controls.OBC.CDL.Reals.Subtract sub1[nRelFan] "Identify next operating fan"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr1[nRelFan]( final t=fill(0.5, nRelFan)) "Check if the input is less than threshold"; Buildings.Controls.OBC.CDL.Reals.AddParameter addPar[nRelFan]( final p=fill(nRelFan + 1, nRelFan)) "Add value to the input"; Buildings.Controls.OBC.CDL.Reals.Switch swi[nRelFan] "Switch input values"; Buildings.Controls.OBC.CDL.Reals.Abs abs1[nRelFan] "Find absolute value"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr2[nRelFan]( final t=fill(0.5, nRelFan)) "Identify next operating fan"; Buildings.Controls.OBC.CDL.Logical.Or or2[nRelFan] "Targeted vector of operating relief fan after one new fan being turned on"; Buildings.Controls.OBC.CDL.Logical.Latch lat2 "Stage up next relief fan"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr3( final t=relFanSpe_min, final h=hys) "Check if the controller output is less than minimum speed"; Buildings.Controls.OBC.CDL.Logical.Timer dowTim( final t=300) "Check if the controller output has been less than threshold for sufficient long time"; Buildings.Controls.OBC.CDL.Logical.Pre pre1( final pre_u_start=true) "Break algebraic loop"; Buildings.Controls.OBC.CDL.Reals.Multiply pro2[nRelFan] "List of operating fans, along with their staging order"; Buildings.Controls.OBC.CDL.Reals.AddParameter addPar1[nRelFan]( final p=fill(nRelFan + 1, nRelFan)) "Add value to the input"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr4[nRelFan]( final t=fill(0.5, nRelFan)) "Check if the input is less than threshold"; Buildings.Controls.OBC.CDL.Reals.Switch swi1[nRelFan] "Switch input values"; Buildings.Controls.OBC.CDL.Reals.MultiMin mulMin1( final nin=nRelFan) "Minimum staging order of the running relief fans"; Buildings.Controls.OBC.CDL.Reals.Subtract sub3[nRelFan] "Identify next operating fan"; Buildings.Controls.OBC.CDL.Reals.Abs abs2[nRelFan] "Find absolute value"; Buildings.Controls.OBC.CDL.Reals.LessThreshold lesThr5[nRelFan]( final t=fill(0.5, nRelFan)) "Identify next fan to be off"; Buildings.Controls.OBC.CDL.Routing.RealScalarReplicator reaRep1( final nout=nRelFan) "Replicate real number"; Buildings.Controls.OBC.CDL.Logical.Xor xor[nRelFan] "Vector of relief fan after one fan being turned off"; Buildings.Controls.OBC.CDL.Conversions.BooleanToInteger booToInt[nRelFan] "Convert boolean to integer"; Buildings.Controls.OBC.CDL.Conversions.BooleanToInteger booToInt1[nRelFan] "Convert boolean to integer"; Buildings.Controls.OBC.CDL.Conversions.BooleanToInteger booToInt2[nRelFan] "Convert boolean to integer"; Buildings.Controls.OBC.CDL.Integers.Equal intEqu[nRelFan] "Check if newly started fan has become proven on"; Buildings.Controls.OBC.CDL.Logical.MultiAnd mulAnd( final nin=nRelFan) "Check if newly started fan has become proven on"; Buildings.Controls.OBC.CDL.Integers.Equal intEqu1[nRelFan] "Check if newly turned off fan has become off"; Buildings.Controls.OBC.CDL.Logical.MultiAnd mulAnd2( final nin=nRelFan) "Check if newly turned off fan has become off"; Buildings.Controls.OBC.CDL.Logical.Latch lat1 "Stage down lag fan"; Buildings.Controls.OBC.CDL.Logical.Switch logSwi[nRelFan] "Vector of relief fan status after staging up"; Buildings.Controls.OBC.CDL.Routing.BooleanScalarReplicator booRep1( final nout=nRelFan) "Replicate boolean input"; Buildings.Controls.OBC.CDL.Logical.Switch logSwi1[nRelFan] "Vector of relief fan status after staging down"; Buildings.Controls.OBC.CDL.Routing.BooleanScalarReplicator booRep2( final nout=nRelFan) "Replicate boolean input"; Buildings.Controls.OBC.CDL.Conversions.BooleanToReal booToRea3[nRelFan] "Convert boolean to real"; Buildings.Controls.OBC.CDL.Reals.Limiter lim( final uMax=1, final uMin=relFanSpe_min) "Limit the controller output"; Buildings.Controls.OBC.CDL.Routing.RealScalarReplicator reaRep2( final nout=nRelFan) "Replicate real input"; Buildings.Controls.OBC.CDL.Reals.Multiply pro3[nRelFan] "Relief fan speed"; Buildings.Controls.OBC.CDL.Logical.Switch logSwi2[nRelFan] "Vector of relief fan status after staging up"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant dpBuiSetPoi( final k=dpBuiSet) "Building pressure setpoint"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant conOne( final k=1) "Constant one"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant con( final k=0) "Zero fan speed when it is in stage 0"; Buildings.Controls.OBC.CDL.Reals.Switch swi2 "Switch input values"; Buildings.Controls.OBC.CDL.Logical.MultiOr mulOr(nin=nRelFan) "Check if there is any relief fan enabled, but may not be running"; Buildings.Controls.OBC.CDL.Conversions.BooleanToReal booToRea4[nRelFan] "Convert boolean to real"; Buildings.Controls.OBC.CDL.Logical.Not not1 "Logical not"; Buildings.Controls.OBC.CDL.Logical.And and1 "Start timer, and reset to zero if the threshold time has passed"; Buildings.Controls.OBC.CDL.Logical.And and3 "Start timer, and reset to zero if the threshold time has passed"; Buildings.Controls.OBC.CDL.Logical.Not not2 "Logical not"; Buildings.Controls.OBC.CDL.Integers.Equal intEqu2[nRelFan] "Check if the relief fan is in level 2 alarm"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant conInt[nRelFan]( final k=fill(2, nRelFan)) "Constant"; Buildings.Controls.OBC.CDL.Logical.Not not3[nRelFan] "Logical not"; Buildings.Controls.OBC.CDL.Logical.And and4[nRelFan] "Check if the relief fan is in level 2 alarm and it is proven off"; Buildings.Controls.OBC.CDL.Conversions.BooleanToReal booToRea5[nRelFan]( final realTrue=fill(0, nRelFan), final realFalse=fill(1, nRelFan)) "Convert boolean to real"; Buildings.Controls.OBC.CDL.Reals.Multiply mul[nRelFan] "Product of inputs"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold greThr3[nRelFan]( final t=fill(0.5, nRelFan)) "Check if the relief fan is enabled"; Buildings.Controls.OBC.CDL.Logical.MultiAnd mulAnd1( final nin=nRelFan) "Check if all the fans are proven off"; Buildings.Controls.OBC.CDL.Reals.Switch swi3[nRelFan] "Switch input values"; Buildings.Controls.OBC.CDL.Routing.BooleanScalarReplicator booRep4( final nout=nRelFan) "Replicate boolean input"; Buildings.Controls.OBC.CDL.Logical.Switch logSwi3[nRelFan] "Vector of relief fan status after staging down"; Buildings.Controls.OBC.CDL.Logical.TrueDelay truDel[nRelFan]( final delayTime=fill(2, nRelFan)) "Delay true input"; Buildings.Controls.OBC.CDL.Logical.MultiOr mulOr1( final nin=nRelFan) "Check if there is any fan is proven on"; Buildings.Controls.OBC.CDL.Routing.BooleanScalarReplicator booRep5( final nout=nRelFan) "Replicate boolean input"; Buildings.Controls.OBC.CDL.Logical.Not not5[nRelFan] "Logical not"; Buildings.Controls.OBC.CDL.Logical.Not not6[nRelFan] "Logical not"; Buildings.Controls.OBC.CDL.Logical.TrueDelay truDel1[nRelFan]( final delayTime=fill(2, nRelFan)) "Delay true input"; equation connect(u1SupFan, booToRea.u); connect(enaRel.u, booToRea.y); connect(enaRel.y, gai.u); connect(dpBui, movMea.u); connect(conOne.y, conP.u_s); connect(movMea.y, div1.u1); connect(dpBuiSetPoi.y, div1.u2); connect(div1.y, conP.u_m); connect(u1SupFan, enaRelGro.u); connect(booToRea1.y, pro.u1); connect(enaRelGro.y, booToRea1.u); connect(conP.y, greThr.u); connect(enaRelGro.y, and2.u2); connect(greThr.y, and2.u1); connect(and2.y, lat.u); connect(conP.y, lesThr.u); connect(lesThr.y, tim.u); connect(tim.passed, lat.clr); connect(lat.y, booRep.u); connect(gai.y, greThr1.u); connect(greThr1.y, enaDam.u1); connect(booRep.y, enaDam.u2); connect(u1RelFan, booToRea2.u); connect(enaRel.y, sub2.u1); connect(booToRea2.y, sub2.u2); connect(gai.y, pro1.u1); connect(sub2.y, pro1.u2); connect(mulMin.y, reaRep.u); connect(lesThr1.y, swi.u2); connect(pro1.y, swi.u3); connect(pro1.y, addPar.u); connect(addPar.y, swi.u1); connect(gai.y, sub1.u1); connect(reaRep.y, sub1.u2); connect(sub1.y, abs1.u); connect(abs1.y, lesThr2.u); connect(lesThr2.y, or2.u1); connect(booToRea2.y, pro2.u2); connect(gai.y, pro2.u1); connect(pro2.y, addPar1.u); connect(pro2.y, lesThr4.u); connect(lesThr4.y, swi1.u2); connect(addPar1.y, swi1.u1); connect(pro2.y, swi1.u3); connect(swi1.y, mulMin1.u); connect(mulMin1.y, reaRep1.u); connect(reaRep1.y, sub3.u2); connect(gai.y, sub3.u1); connect(sub3.y, abs2.u); connect(abs2.y, lesThr5.u); connect(lesThr5.y, xor.u1); connect(booToInt.y, intEqu.u1); connect(booToInt1.y, intEqu.u2); connect(intEqu.y, mulAnd.u); connect(booToInt1.y, intEqu1.u1); connect(booToInt2.y, intEqu1.u2); connect(intEqu1.y, mulAnd2.u); connect(lat2.y, booRep1.u); connect(lat1.y, booRep2.u); connect(booRep2.y, logSwi1.u2); connect(mulAnd2.y, lat1.clr); connect(conP.y, lesThr3.u); connect(xor.y, logSwi1.u1); connect(conP.y, greThr2.u); connect(booRep1.y, logSwi.u2); connect(or2.y, logSwi.u1); connect(u1RelFan, xor.u2); connect(u1RelFan, logSwi1.u3); connect(u1RelFan, booToInt1.u); connect(u1RelFan, or2.u2); connect(logSwi.y, booToRea3.u); connect(conP.y, lim.u); connect(lim.y, pro.u2); connect(booToRea3.y, pro3.u2); connect(pro3.y, yRelFan); connect(reaRep2.y, pro3.u1); connect(con.y, swi2.u3); connect(mulOr.y, swi2.u2); connect(movMea.y, yDpBui); connect(logSwi2.y, booToRea4.u); connect(not1.y, pre.u); connect(and1.y, upTim.u); connect(greThr2.y, and1.u1); connect(not2.y, pre1.u); connect(lesThr3.y, and3.u1); connect(and3.y, dowTim.u); connect(uRelFanAla, intEqu2.u1); connect(conInt.y, intEqu2.u2); connect(u1RelFan, not3.u); connect(intEqu2.y, and4.u1); connect(not3.y, and4.u2); connect(and4.y, booToRea5.u); connect(booToRea4.y, mul.u1); connect(booToRea5.y, mul.u2); connect(mul.y, yDam); connect(enaDam.y, logSwi2.u3); connect(logSwi.y, logSwi2.u1); connect(upTim.passed, not1.u); connect(upTim.passed, lat2.u); connect(dowTim.passed, not2.u); connect(dowTim.passed, lat1.u); connect(enaRel.y, greThr3.u); connect(greThr3.y, mulOr.u); connect(pro.y, swi2.u1); connect(swi2.y, reaRep2.u); connect(pro1.y, lesThr1.u); connect(not3.y, mulAnd1.u); connect(mulAnd1.y, booRep4.u); connect(booRep4.y, swi3.u2); connect(pro1.y, swi3.u1); connect(swi.y, swi3.u3); connect(swi3.y, mulMin.u); connect(pre1.y, and3.u2); connect(u1RelFan, logSwi3.u1); connect(booRep4.y, logSwi3.u2); connect(logSwi1.y, logSwi3.u3); connect(logSwi3.y, logSwi.u3); connect(pre.y, and1.u2); connect(truDel.y, booToInt.u); connect(or2.y, truDel.u); connect(mulAnd.y, lat2.clr); connect(logSwi.y, mulOr1.u); connect(mulOr1.y, booRep5.u); connect(booRep5.y, logSwi2.u2); connect(not6.y, booToInt2.u); connect(truDel1.y, not6.u); connect(not5.y, truDel1.u); connect(xor.y, not5.u); end ReliefFanGroup;

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReturnFan Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReturnFan

Return fan control for single zone AHU

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.ReturnFan

Information

Sequence for controlling return fan yRetFan for single AHUs. It is implemented according to Section 5.18.10 of ASHRAE Guideline G36, May 2020.

Parameters

TypeNameDefaultDescription
RealspeDif-0.1Speed difference between supply and return fan to maintain building pressure at desired pressure

Connectors

TypeNameDescription
input RealInputuSupFan_actualActual supply fan speed [1]
input BooleanInputu1SupFanSupply fan command on
output BooleanOutputy1ExhDamExhaust damper commanded on
output RealOutputyRetFanReturn fan commanded speed [1]
output BooleanOutputy1RetFanReturn fan command on

Modelica definition

block ReturnFan "Return fan control for single zone AHU" parameter Real speDif=-0.1 "Speed difference between supply and return fan to maintain building pressure at desired pressure"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uSupFan_actual( final min=0, final max=1, final unit="1") "Actual supply fan speed"; Buildings.Controls.OBC.CDL.Interfaces.BooleanInput u1SupFan "Supply fan command on"; Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput y1ExhDam "Exhaust damper commanded on"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput yRetFan( final unit="1", final min=0, final max=1) "Return fan commanded speed"; Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput y1RetFan "Return fan command on"; Buildings.Controls.OBC.CDL.Reals.AddParameter addPar( final p=speDif) "Adjusted return fan speed"; Buildings.Controls.OBC.CDL.Reals.Switch swi "Return fan speed"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant con( final k=0) "Zero speed"; equation connect(uSupFan_actual, addPar.u); connect(u1SupFan, swi.u2); connect(con.y, swi.u3); connect(addPar.y, swi.u1); connect(swi.y, yRetFan); connect(u1SupFan, y1ExhDam); connect(u1SupFan, y1RetFan); end ReturnFan;

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.Supply Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.Supply

Supply air set point for single zone VAV system

Buildings.Controls.OBC.ASHRAE.G36.AHUs.SingleZone.VAV.SetPoints.Supply

Information

Block that outputs the set points for the supply air temperature for cooling, heating and economizer control, and the fan speed for a single zone VAV system. The implementation is according to the Section 5.18.4 of ASHRAE Guideline 36, May 2020.

Fan speed setpoint

The supply fan shall run whenever the unit is in any mode other than unoccupied mode. Also, a ramp function should be applied to prevent changes in fan speed of more than 10% per minute.

Minimum, medium, and maximum fan speeds shall be as follows:
  1. Minimum speed minSpe, maximum cooling speed maxCooSpe, and maximum heatng speed maxHeaSpe shall be given per Section 3.2.2.1 of ASHRAE Guideline 36.
  2. Medium fan speed shall be reset linearly based on outdoor air temperature TOut from minSpe when outdoor air temperature is greater than or equal to Endpoint 1 to maxCooSpe when TOut is less than or equal to Endpoint 2.
    • Endpoint 1: the lesser of zone temperature TZon plus 0.5 °C (1 °F) and maximum supply air dew point TSupDew_max.
    • Endpoint 2: the lesser of zone temperature TZon minus 6 °C (10 °F) and maximum supply air dew point TSupDew_max minus 1 °C (2 °F).
Control mapping
  1. For a heating-loop signal uHea of 100% to spePoiOne (default 50%), fan speed is reset from maxHeaSpe to minSpe.
  2. For a heating-loop signal uHea of spePoiOne to 0%, fan speed set point is minSpe.
  3. In deadband (uHea=0, uCoo=0), fan speed set point is minSpe.
  4. For a cooling-loop signal uCoo of 0% to spePoiTwo (default 25%), fan speed is minSpe.
  5. For a cooling-loop signal uCoo of spePoiTwo to spePoiThr (default 50%), fan speed is reset from minSpe to medium fan speed.
  6. For a cooling-loop signal uCoo of spePoiThr to spePoiFou (default 75%), fan speed is medium.
  7. For a cooling-loop signal of uCoo spePoiFou to 100%, fan speed is reset from medium to maxCooSpe.

The figure below shows the sequence.

Image of speed reset

Supply temperature setpoints

The output TSupCooSet is to be used to control the cooling coil, and the output TSupHeaEcoSet is to be used to control the heating coil and the economizer dampers.

When it is in deadband state, the output TSupCooSet and TSupHeaEcoSet shall be average of the zone heating setpoint THeaSet and the zone cooling setpoint TCooSet but shall be no lower than TSupDea_min, 21 °C (70 °F), and no higher than TSupDea_max, 24 °C (75 °F),

Control mapping
  1. For a heating-loop signal uHea of 100% to temPoiOne (default 50%), TSupHeaEcoSet should be TSup_max.
  2. For a heating-loop signal uHea of temPoiOne to 0%, TSupHeaEcoSet is reset from TSup_max to the deadband value.
  3. In deadband (uHea=0, uCoo=0), TSupHeaEcoSet is the deadband value.
  4. For a cooling-loop signal uCoo of 0% to temPoiTwo (default 25%), TSupHeaEcoSet is reset from deadband value to TSup_min minus 1 °C (2 °F), while TSupCooSet is the deadband value.
  5. For a cooling-loop signal uCoo of temPoiTwo to temPoiThr (default 50%), TSupHeaEcoSet and TSupCooSet are unchanged.
  6. For a cooling-loop signal uCoo of temPoiThr to temPoiFou (default 75%), TSupHeaEcoSet remains at TSup_min minus 1 °C (2 °F), while TSupCooSet is reset from the deadband value to TSup_min.
  7. For a cooling-loop signal uCoo of temPoiFou to 100%, TSupHeaEcoSet and TSupCooSet are unchanged.

The figure below shows the sequence.

Image of temperature reset

Note that the inputs uHea and uCoo must be computed based on the same temperature sensors and control loops.

Parameters

TypeNameDefaultDescription
Temperatures
RealTSup_max Maximum supply air temperature for heating [K]
RealTSup_min Minimum supply air temperature for cooling [K]
RealTSupDew_max Maximum supply air dew-point temperature. It's typically only needed in humid type “A” climates. A typical value is 17°C. For mild and dry climates, a high set point (e.g. 24°C) should be entered for maximum efficiency [K]
RealTSupDea_min294.15Minimum supply temperature when it is in deadband state [K]
RealTSupDea_max297.15Maximum supply temperature when it is in deadband state [K]
Speed
RealmaxHeaSpe Maximum fan speed for heating [1]
RealmaxCooSpe Maximum fan speed for cooling [1]
RealminSpe Minimum fan speed [1]
Advanced
ReallooHys0.01Loop output hysteresis below which the output will be seen as zero [1]
Temperatures
RealtemPoiOne0.5Point 1 on x-axis of control map for temperature control, when it is in heating state [1]
RealtemPoiTwo0.25Point 2 on x-axis of control map for temperature control, when it is in cooling state [1]
RealtemPoiThr0.5Point 3 on x-axis of control map for temperature control, when it is in cooling state [1]
RealtemPoiFou0.75Point 4 on x-axis of control map for temperature control, when it is in cooling state [1]
Speed
RealspePoiOne0.5Point 1 on x-axis of control map for speed control, when it is in heating state [1]
RealspePoiTwo0.25Point 2 on x-axis of control map for speed control, when it is in cooling state [1]
RealspePoiThr0.5Point 3 on x-axis of control map for speed control, when it is in cooling state [1]
RealspePoiFou0.75Point 4 on x-axis of control map for speed control, when it is in cooling state [1]

Connectors

TypeNameDescription
input IntegerInputuOpeModAHU operation mode status signal
input RealInputTZonZone temperature [K]
input RealInputTOutOutdoor air temperature [K]
input RealInputuHeaHeating control signal [1]
input RealInputuCooCooling control signal [1]
input RealInputTCooSetCooling setpoints for zone temperature [K]
input RealInputTHeaSetHeating setpoints for zone temperature [K]
output RealOutputyFan speed [1]
output BooleanOutputy1SupFanSupply fan commanded status
output RealOutputTSupHeaEcoSetTemperature setpoint for heating coil and for economizer [K]
output RealOutputTSupCooSetCooling supply air temperature setpoint [K]

Modelica definition

block Supply "Supply air set point for single zone VAV system" parameter Real TSup_max( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Maximum supply air temperature for heating"; parameter Real TSup_min( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Minimum supply air temperature for cooling"; parameter Real TSupDew_max( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Maximum supply air dew-point temperature. It's typically only needed in humid type “A” climates. A typical value is 17°C. For mild and dry climates, a high set point (e.g. 24°C) should be entered for maximum efficiency"; parameter Real TSupDea_min( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature")=294.15 "Minimum supply temperature when it is in deadband state"; parameter Real TSupDea_max( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature")=297.15 "Maximum supply temperature when it is in deadband state"; parameter Real maxHeaSpe( final min=0, final max=1, final unit="1") "Maximum fan speed for heating"; parameter Real maxCooSpe( final min=0, final max=1, final unit="1") "Maximum fan speed for cooling"; parameter Real minSpe( final min=0, final max=1, final unit="1") "Minimum fan speed"; parameter Real looHys( final unit="1")=0.01 "Loop output hysteresis below which the output will be seen as zero"; parameter Real temPoiOne( final unit="1", final min=0, final max=1)=0.5 "Point 1 on x-axis of control map for temperature control, when it is in heating state"; parameter Real temPoiTwo( final unit="1", final min=0, final max=1)=0.25 "Point 2 on x-axis of control map for temperature control, when it is in cooling state"; parameter Real temPoiThr( final unit="1", final min=0, final max=1)=0.5 "Point 3 on x-axis of control map for temperature control, when it is in cooling state"; parameter Real temPoiFou( final unit="1", final min=0, final max=1)=0.75 "Point 4 on x-axis of control map for temperature control, when it is in cooling state"; parameter Real spePoiOne( final unit="1", final min=0, final max=1)=0.5 "Point 1 on x-axis of control map for speed control, when it is in heating state"; parameter Real spePoiTwo( final unit="1", final min=0, final max=1)=0.25 "Point 2 on x-axis of control map for speed control, when it is in cooling state"; parameter Real spePoiThr( final unit="1", final min=0, final max=1)=0.5 "Point 3 on x-axis of control map for speed control, when it is in cooling state"; parameter Real spePoiFou( final unit="1", final min=0, final max=1)=0.75 "Point 4 on x-axis of control map for speed control, when it is in cooling state"; Buildings.Controls.OBC.CDL.Interfaces.IntegerInput uOpeMod "AHU operation mode status signal"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TZon( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Zone temperature"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TOut( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Outdoor air temperature"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uHea( final min=0, final max=1, final unit="1") "Heating control signal"; Buildings.Controls.OBC.CDL.Interfaces.RealInput uCoo( final min=0, final max=1, final unit="1") "Cooling control signal"; Buildings.Controls.OBC.CDL.Interfaces.RealInput TCooSet( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Cooling setpoints for zone temperature"; Buildings.Controls.OBC.CDL.Interfaces.RealInput THeaSet( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Heating setpoints for zone temperature"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput y( final min=0, final max=1, final unit="1") "Fan speed"; Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput y1SupFan "Supply fan commanded status"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput TSupHeaEcoSet( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Temperature setpoint for heating coil and for economizer"; Buildings.Controls.OBC.CDL.Interfaces.RealOutput TSupCooSet( final unit="K", displayUnit="degC", final quantity="ThermodynamicTemperature") "Cooling supply air temperature setpoint"; protected Buildings.Controls.OBC.CDL.Reals.Sources.Constant fanOff( final k=0) "Fan off status"; Buildings.Controls.OBC.CDL.Reals.Switch fanSpe "Supply fan speed"; Buildings.Controls.OBC.CDL.Reals.LimitSlewRate ramLim( final raisingSlewRate=1/600, final Td=60) "Prevent changes in fan speed of more than 10% per minute"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant maxDewPoi( final k=TSupDew_max) "Maximum supply air dew-point temperature"; Buildings.Controls.OBC.CDL.Reals.AddParameter addPar( final p=-1) "Maximum supply dewpoint temperature minus threshold"; Buildings.Controls.OBC.CDL.Reals.AddParameter addPar1( final p=-6) "Zone temperature minus threshold"; Buildings.Controls.OBC.CDL.Reals.AddParameter addPar2( final p=0.5) "Zone temperature plus threshold"; Buildings.Controls.OBC.CDL.Reals.Min endPoiTwo "End point two for specifying medium fan speed"; Buildings.Controls.OBC.CDL.Reals.Min endPoiOne "End point one for specifying medium fan speed"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant minFanSpe( final k=minSpe) "Minimum fan speed"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant maxCooFanSpe( final k=maxCooSpe) "Maximum fan speed for cooling"; Buildings.Controls.OBC.CDL.Reals.Line medFanSpe "Medium fan speed"; Buildings.Controls.OBC.CDL.Reals.Average aveZonSet "Average of the zone heating and cooling setpoint"; Buildings.Controls.OBC.CDL.Reals.Limiter lim( final uMax=TSupDea_max, final uMin=TSupDea_min) "Limiter that outputs the dead band value for the supply air temperature"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant one( final k=1) "Constant one"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant zer( final k=0) "Constant zero"; Buildings.Controls.OBC.CDL.Reals.Line heaFanSpe "Fan speed when it is in heating state"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant speOnePoi( final k=spePoiOne) "Speed control point one in x-axis of control map"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant maxHeaFanSpe( final k=maxHeaSpe) "Maximum fan speed for heating"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant speTwoPoi( final k=spePoiTwo) "Speed control point two in x-axis of control map"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant speThrPoi( final k=spePoiThr) "Speed control point three in x-axis of control map"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant speFouPoi( final k=spePoiFou) "Speed control point four in x-axis of control map"; Buildings.Controls.OBC.CDL.Reals.Line cooFanSpe1 "Fan speed when it is in cooling state"; Buildings.Controls.OBC.CDL.Reals.Line cooFanSpe2 "Fan speed when it is in cooling mode"; Buildings.Controls.OBC.CDL.Reals.Max spe "Fan speed"; Buildings.Controls.OBC.CDL.Reals.Line heaSupTem "Supply air temperature when it is in heating state"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant temOnePoi( final k=temPoiOne) "Temperature control point one in x-axis of control map"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant maxSupTem( final k=TSup_max) "Highest heating supply air temperature"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant temTwoPoi( final k=temPoiTwo) "Temperature control point two in x-axis of control map"; Buildings.Controls.OBC.CDL.Reals.Line cooSupTem "Supply air temperature when it is in cooling state"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant supCooTem( final k=TSup_min) "Cooling supply air temperature"; Buildings.Controls.OBC.CDL.Reals.AddParameter addPar3( final p=-1) "Minimum cooling supply temperature minus threshold"; Buildings.Controls.OBC.CDL.Reals.Line cooSupTem1 "Supply air temperature when it is in cooling state"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant temThrPoi( final k=temPoiThr) "Temperature control point three in x-axis of control map"; Buildings.Controls.OBC.CDL.Reals.Sources.Constant temFouPoi( final k=temPoiFou) "Temperature control point four in x-axis of control map"; Buildings.Controls.OBC.CDL.Reals.Switch cooFan "Fan speed when it is in cooling state"; Buildings.Controls.OBC.CDL.Reals.GreaterThreshold heaSta( final t=looHys, final h=0.8*looHys) "Check if it is in heating state"; Buildings.Controls.OBC.CDL.Reals.Switch supTemSet "Supply temperature setpoint"; Buildings.Controls.OBC.CDL.Reals.Switch supTemSet1 "Supply temperature setpoint"; Buildings.Controls.OBC.CDL.Integers.Sources.Constant unoMod( final k=Buildings.Controls.OBC.ASHRAE.G36.Types.OperationModes.unoccupied) "Unoccupied mode index"; Buildings.Controls.OBC.CDL.Integers.Equal isUnoMod "Check if it is in unoccupied mode"; Buildings.Controls.OBC.CDL.Logical.Not not1 "Supply fan status"; Buildings.Controls.OBC.CDL.Reals.Greater gre( final h=spePoiFou - spePoiThr) "Check setpoint section"; equation connect(unoMod.y, isUnoMod.u1); connect(uOpeMod, isUnoMod.u2); connect(isUnoMod.y, fanSpe.u2); connect(fanOff.y, fanSpe.u1); connect(fanSpe.y, ramLim.u); connect(maxDewPoi.y, addPar.u); connect(addPar.y, endPoiTwo.u1); connect(addPar1.y, endPoiTwo.u2); connect(addPar2.y, endPoiOne.u1); connect(maxDewPoi.y, endPoiOne.u2); connect(endPoiTwo.y, medFanSpe.x1); connect(maxCooFanSpe.y, medFanSpe.f1); connect(endPoiOne.y, medFanSpe.x2); connect(minFanSpe.y, medFanSpe.f2); connect(TOut, medFanSpe.u); connect(TCooSet, aveZonSet.u1); connect(THeaSet, aveZonSet.u2); connect(aveZonSet.y, lim.u); connect(uHea, heaFanSpe.u); connect(speTwoPoi.y, cooFanSpe1.x1); connect(minFanSpe.y, cooFanSpe1.f1); connect(speThrPoi.y, cooFanSpe1.x2); connect(medFanSpe.y, cooFanSpe1.f2); connect(uCoo, cooFanSpe1.u); connect(speFouPoi.y, cooFanSpe2.x1); connect(medFanSpe.y, cooFanSpe2.f1); connect(one.y, cooFanSpe2.x2); connect(maxCooFanSpe.y, cooFanSpe2.f2); connect(uCoo, cooFanSpe2.u); connect(heaFanSpe.y, spe.u1); connect(uHea, heaSupTem.u); connect(speOnePoi.y, heaFanSpe.x1); connect(minFanSpe.y, heaFanSpe.f1); connect(one.y, heaFanSpe.x2); connect(maxHeaFanSpe.y, heaFanSpe.f2); connect(zer.y, heaSupTem.x1); connect(lim.y, heaSupTem.f1); connect(temOnePoi.y, heaSupTem.x2); connect(maxSupTem.y, heaSupTem.f2); connect(zer.y, cooSupTem.x1); connect(lim.y, cooSupTem.f1); connect(temTwoPoi.y, cooSupTem.x2); connect(supCooTem.y, addPar3.u); connect(addPar3.y, cooSupTem.f2); connect(temThrPoi.y, cooSupTem1.x1); connect(lim.y, cooSupTem1.f1); connect(temFouPoi.y, cooSupTem1.x2); connect(supCooTem.y, cooSupTem1.f2); connect(cooFanSpe1.y, cooFan.u1); connect(cooFanSpe2.y, cooFan.u3); connect(cooFan.y, spe.u2); connect(uHea, heaSta.u); connect(heaSta.y, supTemSet.u2); connect(heaSupTem.y, supTemSet.u1); connect(cooSupTem.y, supTemSet.u3); connect(heaSta.y, supTemSet1.u2); connect(cooSupTem1.y, supTemSet1.u3); connect(heaSupTem.y, supTemSet1.u1); connect(spe.y, fanSpe.u3); connect(ramLim.y, y); connect(supTemSet.y, TSupHeaEcoSet); connect(supTemSet1.y, TSupCooSet); connect(uCoo, cooSupTem.u); connect(uCoo, cooSupTem1.u); connect(TZon, addPar1.u); connect(TZon, addPar2.u); connect(isUnoMod.y, not1.u); connect(not1.y, y1SupFan); connect(speFouPoi.y, gre.u1); connect(uCoo, gre.u2); connect(gre.y, cooFan.u2); end Supply;