blockDisableChillers

Disable devices when the plant is disabled from chiller mode

Information

It disables the devices when the chiller plant is disabled in chiller mode. It is implemented as ASHRAE Guideline 36-2021, section 5.20.2.5 and 5.20.2.7.

When the plant is disabled:

  • Shut off all enabled chillers, if any.
  • For each enabled chiller, close the chilled water isolation valve after 3 minutes or the chiller is not requesting chilled water flow.
  • For each enabled chiller, close the condenser water isolation valve after 3 minutes or the chiller is not requesting condenser water flow.
  • Disable the operating primary chilled water pumps, condenser water pumps, and cooling towers.

Parameters

TypeNameDefaultDescription
Booleanhave_airCoofalseTrue: the plant has air cooled chiller
Booleanhave_WSEtrueTrue if the plant has waterside economizer. When the plant has waterside economizer, the condenser water pump speed must be variable
IntegernChi2Total number of chillers
IntegernChiWatPum2Total number of chilled water pumps
IntegernConWatPum2Total number of condenser water pumps
IntegernTowCel2Total number of cooling tower cells
Booleanhave_fixSpeConWatPumfalseTrue: the plant has fixed speed condenser water pumps. When the plant has waterside economizer, it must be false
Buildings.Controls.OBC.ASHRAE.G36.Plants.Chillers.Types.ActuatorchiIsoValTypBuildings.Controls.OBC.ASHRAE.G36.Plants.Chillers.Types.Actuator.ModulatingChilled water isolation valve type

Connectors

TypeNameDefaultDescription
Buildings.Controls.OBC.CDL.Interfaces.BooleanInput[nChi]uChiChiller commanded on
Buildings.Controls.OBC.CDL.Interfaces.BooleanInput[nChi]uChiWatReqChilled water request status for each chiller
Buildings.Controls.OBC.CDL.Interfaces.BooleanInput[nChi]u1ChiWatIsoValChilled water isolation valve position
Buildings.Controls.OBC.CDL.Interfaces.RealInput[nChi]uChiWatIsoValChiller chilled water isolation valve position
Buildings.Controls.OBC.CDL.Interfaces.BooleanInput[nChi]uConWatReqCondenser water request status for each chiller
Buildings.Controls.OBC.CDL.Interfaces.RealInput[nChi]uConWatIsoValChiller condenser water isolation valve position
Buildings.Controls.OBC.CDL.Interfaces.BooleanInput[nChi]u1ConWatIsoValCondenser water isolation valve commanded setpoint
Buildings.Controls.OBC.CDL.Interfaces.BooleanInput[nChiWatPum]uChiWatPumChilled water pump commanded status
Buildings.Controls.OBC.CDL.Interfaces.RealInputuChiWatPumSpeChilled water pump speed
Buildings.Controls.OBC.CDL.Interfaces.BooleanInputchaProIndicate if there is a stage up or stage down command
Buildings.Controls.OBC.CDL.Interfaces.RealInputuConWatPumSpeCondenser water pump speed
Buildings.Controls.OBC.CDL.Interfaces.BooleanInput[nConWatPum]uConWatPumCondenser water pump commanded status
Buildings.Controls.OBC.CDL.Interfaces.BooleanInputuWSEWater side economizer status: true = ON, false = OFF
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput[nChi]y1ChiWatIsoValChiller chilled water isolation valve commanded setpoint
Buildings.Controls.OBC.CDL.Interfaces.RealOutput[nChi]yChiWatIsoValChiller chilled water isolation valve position setpoints
Buildings.Controls.OBC.CDL.Interfaces.RealOutput[nChi]yConWatIsoValChiller condenser water isolation valve position setpoints
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput[nChi]y1ConWatIsoValCondenser water isolation valve commanded setpoint
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput[nChiWatPum]yChiWatPumChilled water pump commanded status: true-comanded on
Buildings.Controls.OBC.CDL.Interfaces.RealOutputyChiWatPumSpeChilled water pump speed
Buildings.Controls.OBC.CDL.Interfaces.RealOutputyConWatPumSpeCondenser water pump speed
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput[nConWatPum]yConWatPumCondenser water pump commanded status: true-comanded on
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutputyTowCelTrue: the tower cells should be enabled

Components

TypeNameDefaultDescription
Buildings.Controls.OBC.CDL.Logical.TrueDelaytruDelThreshold time after chiller being disabled
Buildings.Controls.OBC.CDL.Logical.MultiOrmulOrCheck if there is any chilled water request
Buildings.Controls.OBC.CDL.Routing.BooleanScalarReplicatorbooScaRep1Replicate boolean input
Buildings.Controls.OBC.CDL.Logical.MultiOrmulOr1Check if there is any condenser water request
Buildings.Controls.OBC.CDL.Routing.BooleanScalarReplicatorbooScaRep2Replicate boolean input
Buildings.Controls.OBC.CDL.Routing.BooleanScalarReplicatorbooScaRep5Replicate boolean input
Buildings.Controls.OBC.CDL.Logical.NotnoChiNo enabled chiller
Buildings.Controls.OBC.CDL.Logical.NotnoChiWatReqNo chilled water request
Buildings.Controls.OBC.CDL.Logical.OrcloChiIsoValClose all chilled water isolation valve
Buildings.Controls.OBC.CDL.Logical.Switch[nChi]logSwiClose valve
Buildings.Controls.OBC.CDL.Logical.OrcloConIsoValClose all condenser water isolation valve
Buildings.Controls.OBC.CDL.Logical.NotnoConWatReqNo condenser water request
Buildings.Controls.OBC.CDL.Reals.Switch[nChi]swi1Close valve
Buildings.Controls.OBC.CDL.Reals.Switchswi2Disable pumps
Buildings.Controls.OBC.CDL.Reals.Switchswi3Disable pumps
Buildings.Controls.OBC.CDL.Logical.Andand2Plant is disabled and it is not in staging process
Buildings.Controls.OBC.CDL.Logical.Andand1Plant is disabled and it is not in staging process
Buildings.Controls.OBC.CDL.Logical.Notnot4Not in staging process
Buildings.Controls.OBC.CDL.Logical.AnddisChi1Chillers are disabled and it is not in staging process
Buildings.Controls.OBC.CDL.Logical.AnddisChiChillers are disabled and it is not in staging process
Buildings.Controls.OBC.CDL.Logical.MultiOrchiModTrue: the plant has chiller mode
Buildings.Controls.OBC.CDL.Reals.Sources.Constant[nChi]conConstant zero
Buildings.Controls.OBC.CDL.Reals.Sources.Constantcon1Constant zero
Buildings.Controls.OBC.CDL.Reals.Sources.Constantcon2Constant zero
Buildings.Controls.OBC.CDL.Logical.Notnot1Not in staging process
Buildings.Controls.OBC.CDL.Logical.AnddisPla1Plant is disabled and it is not in staging process
Buildings.Controls.OBC.CDL.Logical.AnddisPlaPlant is disabled and it is not in staging process
Buildings.Controls.OBC.CDL.Logical.Sources.Constantcon3Logical true
Buildings.Controls.OBC.CDL.Logical.OrdisTowDisable cooling tower
Buildings.Controls.OBC.CDL.Logical.Sources.Constantcon4Logical false
Buildings.Controls.OBC.CDL.Logical.And[nConWatPum]conWatPumCondenser water pump commanded status
Buildings.Controls.OBC.CDL.Logical.Not[nConWatPum]not2Not disable pumps
Buildings.Controls.OBC.CDL.Logical.And[nChiWatPum]chiWatPum1Chilled water pump commanded status
Buildings.Controls.OBC.CDL.Routing.BooleanScalarReplicatorbooScaRep3Replicate boolean input
Buildings.Controls.OBC.CDL.Logical.Not[nChiWatPum]not3Not disable pumps
Buildings.Controls.OBC.CDL.Logical.Sources.Constant[nChi]con6Logical false
Buildings.Controls.OBC.CDL.Reals.Switch[nChi]swi4Close valve
Buildings.Controls.OBC.CDL.Logical.LatchenaIsoValEnable isolation valve
Buildings.Controls.OBC.CDL.Logical.ChangechiWatReqChaAny change on the chilled water request
Buildings.Controls.OBC.CDL.Logical.OrenaChiIsoValEnable chilled water isolation valve
Buildings.Controls.OBC.CDL.Logical.ChangeconWatReqChaAny change on the condenser water request
Buildings.Controls.OBC.CDL.Logical.LatchenaIsoVal1Enable isolation valve
Buildings.Controls.OBC.CDL.Logical.OrenaConIsoValEnable condenser water isolation valve
Buildings.Controls.OBC.CDL.Logical.Sources.Constant[nChi]con5Logical false
Buildings.Controls.OBC.CDL.Logical.Switch[nChi]logSwi1Condenser water isolation valve commended setpoint

Revisions

  • July 20, 2022, by Jianjun Hu:
    First implementation.