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Issues Creating Measures - Plug Load Density Example

asked 2017-08-12 16:00:44 -0500

Liam's avatar

updated 2017-08-14 11:40:21 -0500

Hey everyone - first post; read a lot of posts over the years, thanks to everyone who contributes. I'm getting started a little late with OpenStudio and hoping someone can help me iron out some issues I'm having with measure creation using a simple example. I do not have much experience with Ruby or Python, apologies in advance.

I'm looking to create a measure that modifies the Electric Equipment object to set a W/m^2 density. I started with the "Set Lighting Loads by LPD" from the BCL, and did a quick copy/paste of the directory and renamed as "Set Plug Loads by Density". I've tried a couple of modifications (i.e., removing reference to luminaire objects which aren't applicable to plug loads) without success. My thought is that all I should need to do is replace the "LightsDefinition" reference to "ElectricEquipmentDefinition", but I get a failure during 'Processing OpenStudio Measures".

Can anyone shed light on this measure/clarify if I'm not understanding the OS objects correctly?

I'm also seeing two indicators in the Measures screen that I'm hoping someone can also clarify (I don't see in documentation on this site or OS documentation): a red triangle with exclamation point when a measure is dragged into the project, and what looks like a piece of paper broken in the measures library (I assume this means the file is not formatted correctly/missing components).

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answered 2017-08-14 14:25:23 -0500

@Liam, nice first question. "Space Loads Definition" objects are resources that are assigned to a space or space type in the model by a "Space Load Instance" object. The space load instance points a definition, and optionally a schedule (although the schedule can also be inherited from somewhere else). The multiplier field, which defaults to 1, is also important for determining the impact of a the load.

Here is the API link for space load instance and image of sub-classes

image description

It sounds like you may have changed the definition objects to alter "Electric Equipment Definition" objects instead of "Lights Definition" objects, but you have not altered the code for the "Electric Equipment Instance" objects to use the new definitions.

The Reduce Electric Equipment Loads by Percentage measure would be good guide to show methods for getting and altering plug loads.

If you can't get the measure running after this, it may help to have it posted somewhere where we can inspect the code, or to get familiar with testing measure from an IDE or command line outside of the OpenStudio interface.

The think the red triangle indicates a required measure argument that has a default value that hasn't bee entered, and the broken paper is probably indicating a problem loading or running the ruby code from the measure. It could be some like a bad variable name or could be something else.

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Thanks; not sure why I didn't think of modifying the reduce loads by percentage measure!

Liam's avatar Liam  ( 2017-08-14 16:02:11 -0500 )edit

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Asked: 2017-08-12 16:00:44 -0500

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Last updated: Aug 14 '17