Using this setup along with some EMS logic to reset the condenser temperature I can get the WSE to be activated whenever ambient wetbulb conditions allow. However, the chiller doesn't always turn off when it should and stays on with a very low PLR at times because the HX is supplying most of the cooling. I believe this is because the operation schemes that OS is defaulting to.
See timeseries below:
Here are the default schemes that OS translates to E+:
PlantEquipmentOperationSchemes,
Chilled Water Loop Operation Schemes, !- Name
PlantEquipmentOperation:CoolingLoad, !- Control Scheme Object Type 1
Chilled Water Loop Cooling Operation Scheme, !- Control Scheme Name 1
Always On Discrete, !- Control Scheme Schedule Name 1
PlantEquipmentOperation:Uncontrolled, !- Control Scheme Object Type 2
Chilled Water Loop Uncontrolled Operation Scheme, !- Control Scheme Name 2
Always On Discrete, !- Control Scheme Schedule Name 2
PlantEquipmentOperation:ComponentSetpoint, !- Control Scheme Object Type 3
Chilled Water Loop Setpoint Operation Scheme, !- Control Scheme Name 3
Always On Discrete; !- Control Scheme Schedule Name 3
PlantEquipmentOperation:CoolingLoad,
Chilled Water Loop Cooling Operation Scheme, !- Name
0, !- Load Range Lower Limit 1 {W}
1000000000, !- Load Range Upper Limit 1 {W}
Chilled Water Loop Cooling Equipment List; !- Range Equipment List Name 1
PlantEquipmentList,
Chilled Water Loop Cooling Equipment List, !- Name
Chiller:Electric:EIR, !- Equipment Object Type 1
Chiller -2; !- Equipment Name 1
PlantEquipmentOperation:Uncontrolled,
Chilled Water Loop Uncontrolled Operation Scheme, !- Name
Chilled Water Loop Uncontrolled Equipment List; !- Equipment List Name
PlantEquipmentList,
Chilled Water Loop Uncontrolled Equipment List, !- Name
HeatExchanger:FluidToFluid, !- Equipment Object Type 1
Non-Integrated Waterside Economizer HX; !- Equipment Name 1
PlantEquipmentOperation:ComponentSetpoint,
Chilled Water Loop Setpoint Operation Scheme, !- Name
HeatExchanger:FluidToFluid, !- Equipment Object Type 1
Non-Integrated Waterside Economizer HX, !- Equipment Name 1
Node 118, !- Demand Calculation Node Name 1
Node 122, !- Setpoint Node Name 1
Autosize, !- Component Flow Rate 1 {m3/s}
Dual; !- Operation Type 1
Ideally, I would like to use only a 'PlantEquipmentOperation:ComponentSetpoint' scheme and have both pieces of equipment listed in the scheme with the HX having priority. I don't believe this scheme is supported by OS directly. Does anyone have any ideas on how to create this configuration without manipulating the IDF via measure?
Update: I performed a test where the other two operating schemes were disabled and only the 'PlantEquipmentOperation:ComponentSetpoint' scheme was operational. This resulted in no change at all and the WSE and chiller were staged just like before. Given this disregard my previous question. This was surprising for me as I thought the priority of the other operation schemes would impact how equipment was staged.
I thought it maybe had something to do with the min. PLR and min. unloading ratio for the chiller so I ran another test where these were both set to zero instead of 0.1 and 0.2 respectively. To my surprise, this resulted in quite a large penalty as the chiller's baseload increase by over 100 kW. I'm thoroughly confused now...