The power source for submerged arc welding must be rated for a 100 percent duty cycle, since the submerged arc welding operations are continuous and the length of time for making a weld may exceed 10 minutes.

If a 60 percent duty cycle power source is used, it must be derated according to the duty cycle curve for 100 percent operation.

When constant current is used, either ac or dc, the voltage sensing electrode wire feeder system must be used.