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Openstudio - expose HVAC on/off for BCVTB

asked 2020-01-08 03:46:17 -0500

tenna031 gravatar image

updated 2020-01-25 18:20:00 -0500


I'm trying to manually turn on/off an RTU's heating/cooling stages for a basic model via BCVTB but I'm unable to find the relevant control variables on OpenStudio. Would I have to create a ruby measure to create these as EnergyManagementSystemGlobalVariable objects or is there a better way?


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answered 2020-01-09 10:34:19 -0500

you'll need to use EMS / ExternalInterface to work via BCVTB. Those objects are wrapped in OS, so if you set them up correctly, your idf will be posed correctly when you try and run through BCVTB. Most of what you want will need to be done through a measure. This repo contains OS-Measures of the EMS examples EMS-Measures you can use as reference or an editing starting point.

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Thank you for your reply Brian. I will check out the measures in your link.

tenna031 gravatar imagetenna031 ( 2020-01-09 16:56:30 -0500 )edit

here's some ruby/measure code to add the externalinterface object and setup an externalinterface schedule

externalInterface = model.getExternalInterface externalInterface.setNameofExternalInterface("FunctionalMockupUnitExport")

BrianLBall gravatar imageBrianLBall ( 2020-01-09 21:28:41 -0500 )edit

electric_demand =, "Thermal Zone: Steca_Freezer_Cooling_Chamber", "Zone Electric Equipment Electric Power", "electric_demand") electric_heat =, "Q", 0) spaces.each do |space| space.otherEquipment.each do |equip| equip.setSchedule(electric_heat) end end

BrianLBall gravatar imageBrianLBall ( 2020-01-09 21:28:56 -0500 )edit

Hi Brian, thanks much for your comment. wrt to your code above, does this mean EP actually allows us to turn on and off HVAC equipment on demand (e.g. custom heating/cooling loads)? I thought we could only force it off when it should be on and had no control over when to turn on particular stages (stage 1, stage 2).

tenna031 gravatar imagetenna031 ( 2020-02-16 12:17:11 -0500 )edit

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Asked: 2020-01-08 03:46:17 -0500

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Last updated: Jan 09