Voltage Drop Chart

The following table will help calculate the length and gauge of wire required to maintain specified amperage.

Voltage Drop ChartVoltage Calculator

AWG Resistance per foot
18
0.00651
16
0.00402
14
0.00253
12
0.00159
10
0.001
8
0.00063
6
0.0004
4
0.00025
2
0.00016

Voltage Drop = Amps x Resistance x Feet

Example: 150 feet of 14 gauge wire on a 20 amp circuit breaker

150 x 0.00253 x 20 = 7.59 Volt Drop

Therefore, one piece of equipment can operate up to 12 amps.