Incorporate time lag in simulation

savecancel

Hi All,

I'm tring to incorporate an artificial time lag into my simulation, using the EMS. I have a CRAH unit in a data centre and I want the CRAH unit to supply airflow with a delay of 6 time steps from the zone cooling demand sensing. The cooling is controoled via a SetpointManager:SingleZone:Cooling. I am not getting any time lag at all and the CRAH unit rumps up as normal with the increase of the zone cooling demand.

Any thoughts on what I need to ammend to incorporate a time lag? See below my EMS setup.

EnergyManagementSystem:Sensor,
  Energy_Management_System_Sensor_1,      !- Name
  DC,                                     !- Output:Variable or Output:Meter Index Key Name
  Zone Predicted Sensible Load to Cooling Setpoint Heat Transfer Rate; !- Output:Variable or Output:Meter Name

EnergyManagementSystem:Actuator,
  Energy_Management_System_Actuator_1,    !- Name
  Var Spd Fan,                            !- Actuated Component Unique Name
  Fan,                                    !- Actuated Component Type
  Fan Air Mass Flow Rate;                 !- Actuated Component Control Type

EnergyManagementSystem:Actuator,
  Energy_Management_System_Actuator_2,    !- Name
  Node 4,                                 !- Actuated Component Unique Name
  System Node Setpoint,                   !- Actuated Component Type
  Mass Flow Rate Setpoint;                !- Actuated Component Control Type

EnergyManagementSystem:TrendVariable,
  FanFlowDemand_Trend,      !- Name
  Energy_Management_System_Sensor_1,     !- EMS Variable Name
  10;                       !- Number of Timesteps to be Logged

EnergyManagementSystem:Program,
  DelayedFanControl,
  SET Energy_Management_System_Actuator_2 = @TrendValue(FanFlowDemand_Trend 10);

EnergyManagementSystem:ProgramCallingManager,
  RunDelayedFanControl,
  BeginTimestepBeforePredictor,
  DelayedFanControl;

Thank you