Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question

Revision history [back]

@kbk78,

So, I did some digging today with your example file. Unfortunately it has revealed some issues with that operation scheme that are going to require a workaround if you need to use this before the next release of E+.

I have opened an issue on our GitHub site here that details what I have seen so far today. If you have a GitHub account, please feel free to engage in the conversation on that issue. This is a high priority to me, so I anticipate having the issues fixed up soon, but the fix won't be available in a major release until our September 30 release.

In the meantime, if you need an immediate workaround, you could simply pull the outdoor dry bulb from the weather file for every hour, and then create an hourly 0/1 schedule for when the temperature is above or equal to the switch temperature, then one for when it is below. These schedules could be used in the CondenserEquipmentOperationSchemes object to schedule two separate PlantEquipmentOperation: instances. Of which neither should be the OutdoorDryBulb. I would imagine something like:

  CondenserEquipmentOperationSchemes,
    Condenser_Loop Operation,            !- Name
    PlantEquipmentOperation:CoolingLoad, !- Control Scheme 1 Object Type
    AboveScheme,                         !- Control Scheme 1 Name
    AboveSchedule,                       !- Control Scheme 1 Schedule Name
    PlantEquipmentOperation:CoolingLoad, !- Control Scheme 2 Object Type
    BelowScheme,                         !- Control Scheme 2 Name
    BelowSchedule;                       !- Control Scheme 2 Schedule Name

where the AboveSchedule/BelowSchedule are the values you created above outside of E+. (You could use Schedule:File for convenience there). Then the operation schemes would look like:

  PlantEquipmentOperation:CoolingLoad,
    AboveScheme,                 !- Name
    0,                           !- Load Range 1 Lower Limit {W}
    100000000,                   !- Load Range 1 Upper Limit {W}
    CoolingTower Equipment List; !- Range 1 Equipment List Name

  PlantEquipmentOperation:CoolingLoad,
    BelowScheme,                 !- Name
    0,                           !- Load Range 1 Lower Limit {W}
    100000000,                   !- Load Range 1 Upper Limit {W}
    FluidCooler Equipment List;  !- Range 1 Equipment List Name

Thanks for helping identifying this.

@kbk78,

So, I did some digging today with your example file. Unfortunately it has revealed some issues with that operation scheme that are going to require a workaround if you need to use this before the next release of E+.

I have opened an issue on our GitHub site here that details what I have seen so far today. If you have a GitHub account, please feel free to engage in the conversation on that issue. This is a high priority to me, so I anticipate having the issues fixed up soon, but the fix won't be available in a major release until our September 30 release.

In the meantime, if you need an immediate workaround, you could simply pull the outdoor dry bulb from the weather file for every hour, and then create an hourly 0/1 schedule for when the temperature is above or equal to the switch temperature, then one for when it is below. These schedules could be used in the CondenserEquipmentOperationSchemes object to schedule two separate PlantEquipmentOperation: instances. Of which neither should be the OutdoorDryBulb. I would imagine something like:

  CondenserEquipmentOperationSchemes,
    Condenser_Loop Operation,            !- Name
    PlantEquipmentOperation:CoolingLoad, !- Control Scheme 1 Object Type
    AboveScheme,                         !- Control Scheme 1 Name
    AboveSchedule,                       !- Control Scheme 1 Schedule Name
    PlantEquipmentOperation:CoolingLoad, !- Control Scheme 2 Object Type
    BelowScheme,                         !- Control Scheme 2 Name
    BelowSchedule;                       !- Control Scheme 2 Schedule Name

where the AboveSchedule/BelowSchedule are the values you created above outside of E+. (You could use Schedule:File for convenience there). Then the operation schemes would look like:

  PlantEquipmentOperation:CoolingLoad,
    AboveScheme,                 !- Name
    0,                           !- Load Range 1 Lower Limit {W}
    100000000,                   !- Load Range 1 Upper Limit {W}
    CoolingTower Equipment List; !- Range 1 Equipment List Name

  PlantEquipmentOperation:CoolingLoad,
    BelowScheme,                 !- Name
    0,                           !- Load Range 1 Lower Limit {W}
    100000000,                   !- Load Range 1 Upper Limit {W}
    FluidCooler Equipment List;  !- Range 1 Equipment List Name

Thanks for helping identifying this.

So, after the comment by @kbk78, it is clear that there is a set of issues that need to be addressed, and this isn't the location for the conversation to figure it all out (and it will be a lengthy process to work through them all). I would recommend that we close this conversation and continue to work out all the issues together on the GitHub issue page if you already have or are willing to register on GitHub. If you are satisfied with that, please take this as the final answer for the UnmetHours conversation, and we'll work to address this over on the other side.