Syncrowave 250 breaker requirements

[Stricht8]

I picked up a sync 250 a few days ago. I need to get an outlet installed in my garage for it. Do I really need a 100 amp breaker to run this thing? The garage has a 200 amp panel.
Thanks.

[scsmith42]

My 250DX will trip a 50 a breaker when welding 3/8” aluminum. No problems so far on a 70a breaker

[Louie1961]

I have a 200 amp panel in my home and ran a mid-1990's vintage Syncrowave 250 for years. It was wired with 6 gauge conductors, and I originally had a 50 amp breaker. I upgraded the beaker to 110 amps as per the owners manual. I never had a problem with the larger breaker, probably because I never ran the machine long enough to interfere with anything else in the house. I wouldn't let the larger breaker scare you off.

[wb4rt]

I have had mine on a 50 amp breaker for about 8 years with no problem. I have only run on max a couple of times for short runs.

I’m just a hobbyist and rarely weld over 3/16”.

[Louie1961]

The breaker really isn't the issue. In a circuit dedicated to a welder, the electrical codes allow for the breaker to be oversized relative to the wire size, based on duty cycle. The important thing for your welder is to use 6 AWG wire for the circuit, even with a 100 amp breaker. There is no need or reason to go larger on the wire.

[MinnesotaDave]

70 amps works pretty good unless you run heavier aluminum.
I've popped that breaker on my syncrowave 350 with tig aluminum.
100 amp breaker hasn't tripped yet.

[Stricht8]

The breaker really isn't the issue. In a circuit dedicated to a welder, the electrical codes allow for the breaker to be oversized relative to the wire size, based on duty cycle. The important thing for your welder is to use 6 AWG wire for the circuit, even with a 100 amp breaker. There is no need or reason to go larger on the wire.

I spoke with an electrician today. He told me 3 gauge wire! Is that overkill?

[Louie1961]

Absolutely massive overkill. Get the owners manual from the Miller website. They recommend 6AWG wire and a 110 amp breaker.

[Tbones]

Never speak to that electrician again.... unless it's your spouse.

[G-ManBart]

I spoke with an electrician today. He told me 3 gauge wire! Is that overkill?

Yes, it's total overkill!

Most electricians are either ignorant of the NEC section covering dedicated welder circuits or they simply refuse to install one that way. What he's saying is that he would install a 110A breaker and conductors paired to the breaker as if it were intended for a continuous load. Welders (and other non-continuous loads) have different guidelines....Article 630 of the NEC covers the topic.

I've owned something like 15 Syncrowave 250 and Syncrowave 250DX welders in the past few years and all have run perfectly on a 60A circuit without tripping the breaker...ever. I don't normally run it higher than maybe 275A, but I'm sure it would be fine. I've also run most of them on a 40A circuit and have no problems up to 250-260A output.

6ga wire and a 60 or 70A breaker and you'll be totally fine.

[Louie1961]

From the owners manual: https://www.millerwelds.com/support/manuals-and-parts