The two solder pins can't touching, avoid short circuit. The machine power should be plugged into the wall socket. (40A is better) Welding Current Reference: 20A circuit breaker switch can use welding current 20 30A circuit breaker switch can use welding current 30 40A circuit breaker switch can use welding current 40 If you need to use a larger welding current, you can replace the larger circuit breaker switch as needed!
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