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I am trying to check the hourly output of the FAN-EIR-FPLR curve. I have a model with PVVT system type, fan control set to "Fan EIR FPLR", and am using the library curve "Variable Speed Drive FPLR". From the eQUEST help documentation for these curves: "Takes the U-name of a linear, quadratic, or cubic curve that gives the ratio of fan electric energy to full-load fan electric energy, as a function of part-load ratio". I understand the part-load ratio here to be the ratio of the hourly supply airflow to the design airflow (which can be obtained from the SV-A report); this is the curve input, and the output is a multiplier that can be applied to the design fan power (also from the SV-A) to obtain the hourly fan power. To check this, I've created an hourly report to get "Total system supply air flow rate (cfm)" (Var 17) and "Supply fan elec (kW)" (Var 49). However, when I use Var 17 to compute the part-load ratio and put this through the curve for each hour the curve output multiplied by the design fan power doesn't always match the hourly fan power (Var 49). Hopefully I've described this well enough - could someone tell me where I've gone wrong?

I am trying to check the hourly output of the FAN-EIR-FPLR curve. I have a model with PVVT system type, fan control set to "Fan EIR FPLR", and am using the library curve "Variable Speed Drive FPLR". From the eQUEST help documentation for these curves: "Takes the U-name of a linear, quadratic, or cubic curve that gives the ratio of fan electric energy to full-load fan electric energy, as a function of part-load ratio". I understand the part-load ratio here to be the ratio of the hourly supply airflow to the design airflow (which can be obtained from the SV-A report); this is the curve input, and the output is a multiplier that can be applied to the design fan power (also from the SV-A) to obtain the hourly fan power. To check this, I've created an hourly report to get "Total system supply air flow rate (cfm)" (Var 17) and "Supply fan elec (kW)" (Var 49). However, when I use Var 17 to compute the part-load ratio and put this through the curve for each hour the curve output multiplied by the design fan power doesn't always match the hourly fan power (Var 49). Hopefully I've described this well enough - could someone tell me where I've gone wrong?