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Occupancy Sensor Measure Error

asked 2017-05-22 10:48:14 -0500

BL gravatar image

updated 2018-05-09 19:45:56 -0500

I applied the this measure, occupancy_sensors_for_lighting and received following errors, any ideas how to solve ? image description

Besides is there any way to specify which spaces or thermal zones will be controlled by the sensor ? Now it seems like that it will be applied to the entire building.


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@Eric Ringold Do you have any idea how to solve this ?

BL gravatar image BL  ( 2017-05-22 10:48:55 -0500 )edit

Looks like you're tripping the error here. I would start by investigating why lpd_area_change might be returning NaN.

Eric Ringold gravatar image Eric Ringold  ( 2017-05-22 11:54:26 -0500 )edit

Hi @Eric Ringold , can you provide more information to solve ? I defined all space lighting energy as watt/sq ft.

BL gravatar image BL  ( 2017-05-22 12:53:59 -0500 )edit

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answered 2017-05-22 14:50:28 -0500

@Bo_Lin, looks like an issue in the measure that isn't cleanly handing space type that don't have any spaces assigned (or more specifically have a floor area of 0.0), that are flagged as one of these standard space types. As a result we end up dividing by 0 and getting NaN error (Not a Number).

# standards space types
affected_space_types << "BreakRoom"
affected_space_types << "Conference"
affected_space_types << "Office"
affected_space_types << "Restroom"
affected_space_types << "Stair"

I'll file an issue document this so the measure can be updated, but in the mean time try one of these two approaches to resolve the error.

  1. Remove un-used space types from the model, in particular the types listed above.
  2. Instead of removing the space type change the standard type to something else. The measure already has a check to skip it if it isn't one of these types.

Just as a note, if lights in the model are per person, and a space doesn't have any people (as many stairs or restrooms may not, you would hit a similar error, but hopefully those spaces don't have lights defined per person.

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Asked: 2017-05-22 10:48:14 -0500

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Last updated: May 22 '17