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Invalid Output:Variable or Output:Meter Index Key Name

asked 2021-05-20 09:03:56 -0500

sashadf1's avatar

updated 2021-05-20 11:52:20 -0500

Hi all,

I am facing this error in my eplusout.err file after implementing Ideal Air Loads Zone HVAC measure from the BCL, which can be found here;

I ran the Ideal Air Loads Zone HVAC measure with both add_meters: True and add_meters: False as inputs, with the same error occurring.

* Severe * Invalid Output:Variable or Output:Meter Index Key Name =NODE XX

* ~~~ * For Output:Variable or Output:Meter = VARIABLE YY

* ~~~ * Entered in EnergyManagementSystem:Sensor=RES_DS_RES_ASHP_CENTRAL_HTG/CLG_AIR_SYSTEM...

* ~~~ * Unique Key Name not found.

* Fatal * Errors found in processing Energy Management System input. Preceding condition causes termination.

XX, YY indicate different/multiple nodes and output variables, respectively. (i.e., Node 22, Node 29, SYSTEM NODE HUMIDITY RATIO, SYSTEM NODE TEMPERATURE etc.)

I searched through my IDF and could not find an Output:EnergyManagementSystem object; maybe that is the cause of the fatal error?

Please advise! Thanks!

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answered 2021-07-26 13:53:19 -0500

sashadf1's avatar

I created some ruby code that finds all the EMS objects in the model and removes them. These objects were indeed getting "stranded" and needed to be removed through house cleaning (in this case, through a ruby script) for the simulation to be successful.

Ruby code was written that removes all EnergyManagementSystem Sensor, Actuator, GlobalVariable, Program, Subroutine, and ProgramCallingManager objects from the model.

EMS sensor removal code

The script snipping above finds all EnergyManagementSystem:Sensor objects in the model, and stores them in an array ems_sensors. That array is iterated through, and each individual sensor is removed using the .remove method.

Similar lines were written for the other EMS objects (Actuators, Global Variables, etc.)

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answered 2021-05-21 06:27:55 -0500

Craig Simmons's avatar

I would try searching for an energymanagementsystem:Sensor object, since that’s what is directly referenced in the error.

One thing to keep in mind is that the ideal air loads measure deletes zone equipment when it runs. So it may be that some stuff is getting stranded when that happens depending on what you have in the model. You may need to do some preemptive house cleaning to get an ideal air load run.

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Deleting the EMS objects managed to fix the issue.

Deleting all the EMS, output:variables, and output:meters fixed the issue, and the simulation ran with 0 unmet hours.

sashadf1's avatar sashadf1  ( 2021-06-18 17:37:15 -0500 )edit

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Asked: 2021-05-20 09:03:56 -0500

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Last updated: Jul 26 '21