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Hello all,

I am currently trying to simulate a on-off control, that would turn on only if the predicted load is higher than its nominal capacity.

I am using an EMS script for that, using the sensor Zone Predicted Sensible Load to Setpoint Heat Transfer Rate, with the Model Calling Point AfterPredictorAfterHVACManagers, as described in the example file EMSConstantVolumePurchasedAir Until now, I am only sensing the value of the predictor, not actuating anything.

I am getting 3 different results for something I was hoping to be the same :

• The ems sensor Zone Predicted Sensible Load to Setpoint Heat Transfer Rate
• The report DistrictHeating:Facility
• The normal report Output:Variable, *, Zone Predicted Sensible Load to Setpoint Heat Transfer Rate, timestep;

C:\fakepath\Output-1.png

I am pretty sure the difference between the two first is due to the mechanical ventilation loss (with HR).

How can someone get the real load during an EMS simulation?

And why is the last one (=sum of the two zones) that different from the two others?

Thanks !

Hello all,

I am currently trying to simulate a on-off control, that would turn on only if the predicted load is higher than its nominal capacity.

I am using an EMS script for that, using the sensor Zone Predicted Sensible Load to Setpoint Heat Transfer Rate, with the Model Calling Point AfterPredictorAfterHVACManagers, as described in the example file EMSConstantVolumePurchasedAir Until now, I am only sensing the value of the predictor, not actuating anything.

I am getting 3 different results for something I was hoping to be the same :

• The ems sensor Zone Predicted Sensible Load to Setpoint Heat Transfer Rate
• The report DistrictHeating:Facility
• The normal report Output:Variable, *, Zone Predicted Sensible Load to Setpoint Heat Transfer Rate, timestep;

C:\fakepath\Output-1.png

I am pretty sure the difference between the two first is due to the mechanical ventilation loss (with HR). HR) under normal conditions. But there is also a big difference when the thermostat setpoint is changed (+2°C)

How can someone get the real load during an EMS simulation?

And why is the last one (=sum of the two zones) that different from the two others?

Thanks !

I am currently trying to simulate a on-off control, that would turn on only if the predicted load is higher than its nominal capacity.

I am using an EMS script for that, using the sensor Zone Predicted Sensible Load to Setpoint Heat Transfer Rate, with the Model Calling Point AfterPredictorAfterHVACManagers, as described in the example file EMSConstantVolumePurchasedAir

Until now, I am only sensing the value of the predictor, not actuating anything.

I am getting 3 different results for something I was hoping to be the same :

• The ems sensor Zone Predicted Sensible Load to Setpoint Heat Transfer Rate
• The report DistrictHeating:Facility
• The normal report Output:Variable, *, Zone Predicted Sensible Load to Setpoint Heat Transfer Rate, timestep;

C:\fakepath\Output-1.png

I am pretty sure the difference between the two first is due to the mechanical ventilation loss (with HR) under normal conditions. But there is also a big difference when the thermostat setpoint is changed (+2°C)

How can someone get the real load during an EMS simulation?

And why is the last one (=sum of the two zones) that different from the two others?

I am currently trying to simulate a on-off control, that would turn on only if the predicted load is higher than its nominal capacity.

I am using an EMS script for that, using the sensor Zone Predicted Sensible Load to Setpoint Heat Transfer Rate, with the Model Calling Point AfterPredictorAfterHVACManagers, as described in the example file EMSConstantVolumePurchasedAir

Until now, I am only sensing the value of the predictor, not actuating anything.

I am getting 3 different results for something I was hoping to be the same :

• The ems sensor Zone Predicted Sensible Load to Setpoint Heat Transfer Rate
• The report DistrictHeating:Facility
• The normal report Output:Variable, *, Zone Predicted Sensible Load to Setpoint Heat Transfer Rate, timestep;

I am pretty sure the difference between the two first is due to the mechanical ventilation loss (with HR) under normal conditions. But there is also a big difference when the thermostat setpoint is changed (+2°C)

How can someone get the real load during an EMS simulation?

And why is the last one (=sum of the two zones) that different from the two others?

I am currently trying to simulate a on-off control, that would turn on only if the predicted load is higher than its nominal capacity.

I am using an EMS script for that, using the sensor Zone Predicted Sensible Load to Setpoint Heat Transfer Rate, with the Model Calling Point AfterPredictorAfterHVACManagers, as described in the example file EMSConstantVolumePurchasedAir

Until now, I am only sensing the value of the predictor, not actuating anything.

I am getting 3 different results for something I was hoping to be the same :

• The ems sensor Zone Predicted Sensible Load to Setpoint Heat Transfer Rate
• The report DistrictHeating:Facility
• The normal report Output:Variable, *, Zone Predicted Sensible Load to Setpoint Heat Transfer Rate, timestep;

I am pretty sure the difference between the two first is due to the mechanical ventilation loss (with HR) under normal conditions. But there is also a big difference when the thermostat setpoint is changed (+2°C)

How can someone get the real load during an EMS simulation?

And why is the last one (=sum of the two zones) that different from the two others?