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K2A Sensor Calculations

K2A Sensor Calculations

WennSoft has predefined sensor calculations to choose from when creating your calculated sensors.

Name

Formula

Name

Formula

Cooling Air Temperature Deviation

Cooling Air Temperature Setpoint - Cooling Air Temperature

Chilled Water Approach

(Evaporator Leaving Water Temperature) – (Evaporator Saturated Refrigerant Temperature)

Condenser Water Approach

(Condenser Saturated Refrigerant Temperature) – (Condenser Leaving Water Temperature)

Chilled Water Delta T

(Evaporator Entering Water Temp) – (Evaporator Leaving Water Temp)

Condenser Water Delta T

(Condenser Leaving Water Temp) – (Condenser Entering Water Temp)

Differential Steam Pressure Deviation

(abs(Differential Steam Pressure Setpoint - Differential Steam Pressure) / max(0.1, Differential Steam Pressure Setpoint)) * 100

Differential Water Pressure Deviation

(abs(Differential Water Pressure Setpoint - Differential Steam Pressure) / max(0.1, Differential Water Pressure Setpoint)) * 100

Heating Air Temperature Deviation

Heating Air Temperature Setpoint - Heating Air Temperature

Outside Air Dewpoint

Celcius to Celsius Formula
Ts = (243.04 × ln(RH / 100) + 17.625 T/(243.04  + T)) / (17.625 - ln(RH / 100) + 17.625 T/(243.04+T))

Fahrenheit to Fahrenheit Formula
Ts = [ (243.04 × ln(RH / 100) + 17.625 * ((T - 32) * 5/9)/( 243.04  + ((T - 32) * 5/9)) ) / (17.625 - ln(RH / 100) + 17.625 * ((T - 32) * 5/9)/(243.04 + ((T - 32) * 5/9))) ] * 9/5 + 32

Fahrenheit to Celcius Formula
Ts = (243.04 × ln(RH / 100) + 17.625 * ((T - 32) * 5/9)/( 243.04  + ((T - 32) * 5/9)) ) / (17.625 - ln(RH / 100) + 17.625 * ((T - 32) * 5/9)/(243.04 + ((T - 32) * 5/9)))

T: Outside Air temperature
RH: Outside Air Relative Humidity

T and RH are existing sensors.

Outside Air Wet Bulb

Celcius to Celsius Formula
Tw ​= T arctan(0.151977 (RH + 8.313659)1/2) + arctan(T + RH) − arctan(RH − 1.676331) + 0.00391838(RH)3/2arctan(0.023101RH) − 4.686035

Fahrenheit to Fahrenheit Formula
Tw ​= [ ((T - 32) * 5/9) * arctan(0.151977 (RH + 8.313659)1/2) + arctan( ((T - 32) * 5/9) + RH) − arctan(RH − 1.676331) + 0.00391838(RH)3/2arctan(0.023101RH) − 4.686035 ] * 9/5 + 32

Fahrenheit to Celcius Formula
Tw ​= ((T - 32) * 5/9) * arctan(0.151977 (RH + 8.313659)1/2) + arctan( ((T - 32) * 5/9) + RH) − arctan(RH − 1.676331) + 0.00391838(RH)3/2arctan(0.023101RH) − 4.686035 

T: Outside Air temperature
RH: Outside Air Relative Humidity

T and RH are existing sensors.

Power

Current * Voltage

Power (kVa) *coming soon

Power + Power + Power + Power

Primary Differential Water Pressure Deviation

(abs(Primary Differential Water Pressure Setpoint - Primary Differential Water Pressure) / max(0.1, Primary Differential Water Pressure Setpoint)) * 100

Primary Supply Water Temperature

Primary Supply Water Temperature Setpoint - Primary Supply Water Temperature

Secondary Differential Water Pressure Deviation

(abs(Secondary Differential Water Pressure Setpoint - Secondary Differential Water Pressure) / max(0.1, Secondary Differential Water Pressure Setpoint)) * 100

Secondary Supply Water Temperature Deviation

Secondary Supply Water Temperature Setpoint - Secondary Supply Water Temperature

Space Air CO Deviation

Space Air CO Setpoint - Space Air CO

Space Air CO2 Deviation

Space Air CO2 Setpoint - Space Air CO2

Space Air Dewpoint

Space Air Temperature(C) - ((100 - Space Air Relative Humidity) / 5)

Space Air Methane Deviation

Space Air Methane Setpoint - Space Air Methane

Space Air PM2.5 Deviation

Space Air PM2.5 Setpoint - Space Air PM2.5

Space Air Relative Humidity Deviation

Space Air Relative Humidity Setpoint - Space Air Relative Humidity

Space Air Temperature Deviation

Space Air Temperature Setpoint - Space Air Temperature

Space Air TVOC Deviation

Space Air TVOC Setpoint - Space Air TVOC

Supply Air Flow Deviation

(abs(Supply Air Flow Setpoint - Supply Air Flow) / max(0.1, Supply Air Flow Setpoint)) * 100

Supply Air Pressure Deviation

(abs(Supply Air Pressure Setpoint - Supply Air Pressure) / max(0.1, Supply Air Pressure Setpoint)) * 100

Supply Air Temperature Deviation

Supply Air Temperature - Supply Air Temperature Setpoint

Supply Water Flow Deviation

(abs(Supply Water Flow Setpoint - Supply Water Flow) / max(0.1, Supply Water Flow Setpoint)) * 100

Supply Water Temperature Deviation

Supply Water Temperature Setpoint - Supply Water Temperature

Total Runtime

Sum of Time for time given for a True condition.