What is the minimum wire size for a amp circuit? What gauge wire should I use to connect AMP? What size wire for a amp circuit for a welder? For example, plugging a heater rated for amps into a 15- amp circuit wired with 14- gauge wire poses a distinct danger. Should the circuit breaker fail to operate correctly, that heater will draw more current than the wires can safely handle, and could heat the wires to the point of melting the insulation around the wires and igniting.
The length of wire-run should also be factored-in when deciding the correct wire size. To get the right refer to the Wiring Codes. For a maximum of amps, you’ll need a wire gauge of 10. The most common household item that requires a amp circuit is a central air conditioner. Often, people living in RVs use 3 and sometimes 5 amp systems to run all the appliances in the vehicle.
Wire SIZE and voltage Drop calculators (The table is NOT a NEC code just recommendations) For a 20-amp circuit, use 12-gauge wire. For a 15-amp circuit, you can use 14-gauge wire (in most locales). For a long run, though, you should use the next larger size wire. Longer runs may require an upgrade of wire size. In your case, use at least copper for your welder regardless how far it is from the breaker panel.
Instea there are a variety of extension cords available that are designed for RV use.




