I'm in the military and just turned over with a previous construction battalion we have an xmt 304 miller welder. When I turn it on an error pops up saying that the input voltage is too high, or an error will pop up saying the input voltage is too low. If I shut it off and turn it on again it will let me weld for about 30 seconds then the error is back. Just trying to trouble shoot to see if it is fixable.