Electronics   Power Supply   Cable   Loudspeaker   Cable   Home

Wire Diameters For Your Power Supply

The following values for wire diameters are recommendations by ALFATEC a specialist company for car accessories. Longer wires require a larger diameter than suggested by the current flow (heat up) - please refer to DIN table below - since longer wires cause a higher voltage drop, voltage that is needed by your components. That's the reason why ALFATEC chooses relative thick wires for lower and medium currents.
 
Length of copper
wires in metres
0 - 1 1 - 2 2 - 3 3 - 4 4 - 5 5 - 6 6 - 7 7 - 8.5
Current consumption Required wire diameter in mm2
0-20 A 2,5 6 6 6 10 10 10 10
21-36 A 6 6 10 10 20 20 20 35
37-50 A 6 6 10 10 20 20 20 35
51-65 A 10 10 20 35 35 35 35 35
66-85 A 20 20 35 35 35 35 35 35
86-105 A 20 20 35 35 35 35 35 35
106-125 A 35 35 35 35 35 35 35 35
126-150 A 35 35 35 35 35 35 35 35
150-200 A 35 35 50 50 50 50 50 50

In case these wire gauge recommendations seem too large to you, you may confirm these values by using our wire calculator.

The wire calculator calculates the wire's resistance and the voltage drop at 20 C. Then chose the wire diameter, that should be at least as large as indicated in the DIN table below. Finally you should enter the maximum current that you amplifier "draws".

The voltage drop should be below 0.2 Volt for high-end applications and below 0.5 Volt for standard ones.

Wire Calculator

Wire Calculator Resistance exact to three decimal digits at 20 °C
Please enter decimal separator as "."
Wire properties: Length in m: Diameter: max. current: Conductor made of:
 
       
Impedance of a single wire conductor: Ohm Voltage drop of line
(should be less than 0.5 V):
Volt

DIN VDE 0298, Part 2

The following table indicates the maximum current load for a pair of copper wires according to DIN VDE 0298, part 2, laid in air. We believe that this table works well as a guideline.
 
Size Data according to DIN VDE 0298, part 2 for 2-wire conductor in air
Wire diameter in mm2 1.5 2.5 4 6 10 16 25 35 50 70 95
maximum current in A 20 27 37 48 66 89 118 145 176 224 271

  Loudspeakers   Loudspeaker Cable  
back to Electronics   Power Supply Cable   Home