Pulse vs wire size

Thread Starter


Joined Jan 15, 2024
Welder. Spot welder to be exact. Each trigger pull is set to (2) pulses @ 60 amps. And each part it’s used on requires two spots to be welded. So my question is (the voltage drop is not a factor) what is the minimum size wire that can be ran to the spot welder using these specs?


Joined Mar 30, 2018
Wire sizes are based on the heating effect of the current passed (where voltage drop is unimportant), therefore if in a 14 second period, rated current is only flowing for 4 seconds, you can effectively de-rate the peak current by 0.29; giving 15.7A as an average value.

Therefore 1.5mm^2 or 14AWG wire should suffice in terms of the heating effect, but you might like to consider a larger wire size for its mechanical properties; and don’t forget if you were to pass 54A for an extended period you might find that the cable completely loses any insulation covering and starts a fire.