Electrical calculations

 

 

Electrical calculations


Données techniques > Electrical calculations

General formulas for all applications

Wattage (Watt)
Voltage (Volt) 
Intensity (Ampere)
Resistance (Ohm)

Series or parallel wiring of several identical heating elements

R = Total resistance
P = Total wattage
U and I are respectively voltage and intensity of circuit

Parallel wiring

number of heating elements 2, 3 or x
R = r/2 ou R = r/3 ou R= r/x
P= 2.p ou P = 3.p ou P = x.p

For example :
2 parallel-wired heating elements rated at 1000W 230V working with 230V generate 2000W at 230V with R = 26,45 ohms
3 parallel-wired heating elements rated at 1000W 230V working with 230V generate 3000W at 230V with R = 17,63 ohms
etc…

Series wiring

Number of heating elements 2, 3 or x
R= 2.r ou R = 3.r ou R = x.r
P= p/2 ou P = p/3

For example :
2 series-wired heating elements rated at 1000W 230V working with 230V generate 500W at 230V with R = 105,87 ohms (wattage produced by heating elements is 4 times inferior)
3 series-wired heating elements rated at 1000W 230V working with 230V generate 333W at 230V with R = 158,7 ohms (wattage produced by heating elements is 9 times inferior)
etc…

3-phase wiring

Delta connection

Rated voltage of each heating element is identical to voltage between phases in a Delta connection.

Star connection

Rated voltage of heating elements equals to voltage between phases of 3-phase wiring divided by or 1,732


Example of wiring :
3 heating elements rated at 1000W 230V wired to 400V 3-phase supply generate 3000W.
3 heating elements rated at 1000W 400V wired to 400V 3-phase supply generate 1000W.