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EMS output variable unique Key name

asked 2016-01-21 19:11:26 -0600

Rehan Khalid gravatar image

updated 2016-01-21 20:21:02 -0600

Chandan Sharma gravatar image

Hi, I am trying to control data center IT equipment using EMS in EnergyPlus. When I try to get the temperature of air at the server Inlet, Ta_in and the server power dissipation, Qs_dot, I get an error that unique key name for these output variables are not found. Here is what I am currently using:

EnergyManagementSystem:Sensor,
    Tain,                    !- Name
    Zone Equipment Inlet Node ,  !- Output:Variable or Output:Meter Index Key Name
    ITE Air Inlet Dry-Bulb Temperature;  !- Output:Variable or Output:Meter Name

EnergyManagementSystem:Sensor,
    Q_dot_s,                 !- Name
    Whole Building,          !- Output:Variable or Output:Meter Index Key Name
    ITE Total Heat Gain to Zone Rate;  !- Output:Variable or Output:Meter Name

The errors that I get are:

   **   ~~~   ** Severe  ** Invalid Output:Variable or Output:Meter Index Key Name =ZONE EQUIPMENT INLET NODE
   **   ~~~   ** For Output:Variable or Output:Meter = ITE AIR INLET DRY-BULB TEMPERATURE
   **   ~~~   ** Entered in EnergyManagementSystem:Sensor=TAIN
   **   ~~~   ** Unique Key Name not found.
   ** Severe  ** Invalid Output:Variable or Output:Meter Index Key Name =WHOLE BUILDING
   **   ~~~   ** For Output:Variable or Output:Meter = ITE TOTAL HEAT GAIN TO ZONE RATE
   **   ~~~   ** Entered in EnergyManagementSystem:Sensor=Q_DOT_S
   **   ~~~   ** Unique Key Name not found.

Can someone please help me identify what the unique key name should be for these. I have tried a bunch of combinations but none seem to work.

Thanks in advance.

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answered 2016-01-21 21:02:43 -0600

Chandan Sharma gravatar image

1ZoneDataCenterCRAC_wPumpedDXCoolingCoil.idf and 2ZoneDataCenterHVAC_wEconomizer.idf provide a good starting point in this case and they have EMS code which use whole building output variable for EMS sensor. For temperature sensor, instead of "ITE Air Inlet Dry-Bulb Temperature", " System Node Temperature" should be used as follows.

EnergyManagementSystem:Sensor,
    Tain,                    !- Name
    Zone Equipment Inlet Node ,  !- Output:Variable or Output:Meter Index Key Name
    System Node Temperature; !- Output:Variable or Output:Meter Name

Whole building summary output variables which can be used are described in IO reference. "ITE Total Heat Gain to Zone Rate" is not a valid output variable which can be used here.

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Comments

Thank You so much ! That worked ! I had already consulted those files before working on this.

However, I don't understand why my choice of variables does not work. Can you kindly explain.

Thank you once again !

Rehan Khalid gravatar image Rehan Khalid  ( 2016-01-21 23:33:03 -0600 )edit

Answer deleted. I had already posted it as a comment. Thank you for pointing it out.

Rehan Khalid gravatar image Rehan Khalid  ( 2016-01-23 14:43:29 -0600 )edit

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Asked: 2016-01-21 19:11:26 -0600

Seen: 478 times

Last updated: Jan 21 '16