What should power be?

admin

I am hooking up a millermatic 200 in my shop. I have 3 phase power coming in. I put in new 220 single phase 50 amp breaker and plugin. When I energized and checked voltage there was 120 volts on one leg 208 on the other and the 2 hot legs gave me 240 volts.The 208 volt leg is the wild leg from the 3 phase. Will this effect welding or am I ok since the combined 2 hot legs are 240 volt?
Reply:You are fine. The two hot legs are a difference of 240V.The ONLY concern you might have is if you have an open delta (two transformers) rather than a closed delta (three transformers).... In that situation, you want to try to get the two legs that go to the same transformer, not the legs that bridge the open side. This improves voltage stability. Using the wild leg decreases the load on the transformer that supplies all of the standard 120V circuits (lighting, outlets, etc), which is usually the most heavily loaded phase to begin with.
Reply:Thanks for the reply, I just wasn't shure if it made a differance for the welding stability or the welders life expectancy.