Calculate Wire Size Needed
“Voltage Drop Index” method:
Amps x Distance (one way) / Voltage x Percent Loss = VDI
| VDI | Gauge |
|---|---|
| 1 | = # 16 |
| 2 | = # 14 |
| 3 | = # 12 |
| 5 | = # 10 |
| 8 | = # 8 |
| 12 | = # 6 |
| 20 | = # 4 |
| 34 | = # 2 |
| 49 | = # 1/0 |
| 62 | = # 2/0 |
| 78 | = #3/0 |
| 99 | =# 4/0 |
For example,
10 Amps Current
100 Feet one-way distance
24 Volt system
2% Loss
Calculate,
10 x 100 = 20.83
24 x 2
Use #4 Wire