blockUp

Generates a stage up signal

Information

Outputs a boolean stage up signal y based on the various plant operation conditions that get provided as input signals. It is implemented according to Guideline 36-2021, section 5.20.4.15 and applies to primary-only plant with and without a WSE.

The stage up signal becomes true when:

  • Current stage becomes unavailable, or
  • Efficiency condition is true, or
  • Failsafe condition is true.

If have_WSE boolean flag is true, staging up from WSE only to the first available stage occurs when the chilled water supply temperature is sufficienctly above its setpoint for either a shorter or a longer time period

Note that when the plant is enabled in chiller mode, the stage up signal will remain false. The plant will control by the Buildings.Controls.OBC.ASHRAE.G36.Plants.Chillers.Generic.PlantEnable.Enable.

Parameters

TypeNameDefaultDescription
Booleanhave_WSEtruetrue = plant has a WSE, false = plant does not have WSE
Booleanhave_serChifalsetrue = series chillers plant; false = parallel chillers plant
Booleanhave_senDpChiWatRemWirtrueTrue=remote DP sensor hardwired to controller
IntegernRemSen2Total number of remote differential pressure sensors
RealeffConTruDelay900Enable delay for efficiency condition
RealfaiSafTruDelay900Enable delay for failsafe condition
RealshortTDelay600Short enable delay for staging from zero to first available stage up
ReallongTDelay1200Long enable delay for staging from zero to first available stage up
RealfaiSafTDif1Offset between the chilled water supply temperature and its setpoint
RealTDifHys1Hysteresis deadband for temperature
RealsmallTDif1Offset between the chilled water supply temperature and its setpoint for the long condition
ReallargeTDif2Offset between the chilled water supply temperature and its setpoint for the short condition
RealfaiSafDpDif2*6895Offset between the chilled water differential pressure and its setpoint
RealdpDifHys0.5*6895Pressure difference hysteresis deadband
RealeffConSigDif0.05Signal hysteresis deadband

Connectors

TypeNameDefaultDescription
Buildings.Controls.OBC.CDL.Interfaces.BooleanInputuAvaCurCurrent stage availability status
Buildings.Controls.OBC.CDL.Interfaces.IntegerInputuChiller stage
Buildings.Controls.OBC.CDL.Interfaces.RealInputuOpeOperating part load ratio of the current stage
Buildings.Controls.OBC.CDL.Interfaces.RealInputuStaUpStaging part load ratio of the next stage up
Buildings.Controls.OBC.CDL.Interfaces.RealInputdpChiWatSet_localChilled water local diferential static pressure setpoint
Buildings.Controls.OBC.CDL.Interfaces.RealInputdpChiWat_localChilled water diferential static pressure from local sensor
Buildings.Controls.OBC.CDL.Interfaces.RealInput[nRemSen]dpChiWatSet_remoteChilled water remote differential pressure setpoint
Buildings.Controls.OBC.CDL.Interfaces.RealInput[nRemSen]dpChiWat_remoteChilled water differential pressure from remote sensor
Buildings.Controls.OBC.CDL.Interfaces.RealInputTChiWatSupSetChilled water supply temperature setpoint
Buildings.Controls.OBC.CDL.Interfaces.RealInputTChiWatSupChilled water supply temperature
Buildings.Controls.OBC.CDL.Interfaces.BooleanInputuPlaPlant enable signal
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutputyStage up signal

Revisions

  • March 15, 2020, by Milica Grahovac:
    First implementation.