Free wiring tool
Wire Size Calculator (12V / 24V / 48V)
Undersized wire is the most common mistake in DIY solar, and the most dangerous one. Enter your current, your cable run, and your system voltage. This tool hands back the AWG gauge that keeps voltage drop in check, plus the fuse size to protect that wire.
How to use this
- Find the amps. If you only know watts, divide by your system voltage. A 600W load on 12V is 50A.
- Measure the one-way distance from source to load. The tool doubles it for the full circuit.
- Pick 3% drop for solar charge lines and sensitive electronics. 5% is acceptable for short feeder runs to lights or pumps.
Your circuit
Watts ÷ volts = amps. A 360W panel array on 12V pushes about 30A.
Source to load along the actual cable path, not as the crow flies.