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Hi,

When measuring the variable 'Zone ideal air loads Supply air sensible heating energy' with an EMS sensor (blue line in image) I get a different value for certain timesteps then when I ouput the same variable as a regular output variable (red line in image).

I am limiting the heating capacity of the ideal air loads system and the difference only occurs when the system reaches this capacity limit. At those timesteps the EMS sensor measures exactly half of the maximum heating capacity rather than the max.

Any thoughts?

Attached is a one zone model with outputs (see link). Heating capacity is limited to 2400 W. There's a lot of EMS programs in the IDF. In the relevant one (EMS_PRG_setPerfIndc), all I am doing is setting the EMS output variable tot the EMS sensor value.

I have looked into:

• The calling point for the EMS program. This is now set to: EndOfSystemTimestepBeforeHVACReporting. Setting it earlier does not change anything.
• The DesignBuilder resultsviewer changes energy output to power output. The problem does not lie in this converion. I have also checked the energy outputs in the CSV.

Hi,

When measuring the variable 'Zone ideal air loads Supply air sensible heating energy' with an EMS sensor (blue line in image) I get a different value for certain timesteps then when I ouput the same variable as a regular output variable (red line in image).

I am limiting the heating capacity of the ideal air loads system and the difference only occurs when the system reaches this capacity limit. At those timesteps the EMS sensor measures exactly half of the maximum heating capacity rather than the max.

Any thoughts?

Attached is a one zone model with outputs (see link). I am using EnergyPlus 9.2. Heating capacity is limited to 2400 W. There's a lot of EMS programs in the IDF. In the relevant one (EMS_PRG_setPerfIndc), all I am doing is setting the EMS output variable tot the EMS sensor value.

I have looked into:

• The calling point for the EMS program. This is now set to: EndOfSystemTimestepBeforeHVACReporting. Setting it earlier does not change anything.
• The DesignBuilder resultsviewer changes energy output to power output. The problem does not lie in this converion. I have also checked the energy outputs in the CSV.

Hi,

When measuring the variable 'Zone ideal air loads Supply air sensible heating energy' with an EMS sensor (blue line in image) I get a different value for certain timesteps then when I ouput the same variable as a regular output variable (red line in image).

I am limiting the heating capacity of the ideal air loads system and the difference only occurs when the system reaches this capacity limit. At those timesteps the EMS sensor measures exactly half of the maximum heating capacity rather than the max.

Any thoughts?

Attached is a one zone model with outputs (see link). I am using EnergyPlus 9.2. Heating capacity is limited to 2400 W. There's a lot of EMS programs in the IDF. In the relevant one (EMS_PRG_setPerfIndc), all I am doing is setting the EMS output variable tot the EMS sensor value.

I have looked into:

• The calling point for the EMS program. This is now set to: EndOfSystemTimestepBeforeHVACReporting. Setting it earlier does not change anything.
• The DesignBuilder resultsviewer changes energy output to power output. The problem does not lie in this converion. I have also checked the energy outputs in the CSV.