Welding Tips and Tricks

Currently all my welders run off single phase wiring. I do have 3phase on my farm and in my shop even. I’m planning some renovations and a lot of rewiring. I know very little about electrical, it’ll all be done by pros. Should I consider switching my welders to 3phase, and working my shop that way? Are there any pros/cons to one over the other?

Thanks for any info.


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I would say it depends on your machines, but in general, for the same given wire gauge, 3-Φ power lines can deliver greater power, and/or while using less amperage, which is beneficial when it comes to wiring things. You can get by with smaller gauge electrical wires, depending on the 3-Φ voltage. All things equal, higher-voltage 3-Φ lines can provide the same power as lower-voltage 3-Φ lines, but with smaller diameter/gauge conductors. IE: 3-Φ 500V can use conductors roughly half the "size" as 3-Φ 240V conductors (depending on the actual need and power consumption/breaker requirements.

Now a days with the abundance of some inverter welders, some are 1/3-Φ capable, where they can output more welding power on 3-Φ, or perhaps with greater duty cycle. But if you don't already have these machines, you're not really gaining anything, except a lighter wallet, as you'd have to upgrade the breakers and add lines for the additional phase.

That seems to be what I’m finding out, that you can use smaller wiring, and in the case of my PowerMig, I’d gain a bit more duty cycle. But other than the wiring and machines basically running cooler, I wouldn’t gain anything performance wise?


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Every 3 phase welder I've used seems to run smoother & better than on 240 volts - no science to back this up but I think as the arc changes during welding this causes current fluctuations & the higher voltage combined with less time of the supply going through 0 volts gives a smoother more stable arc - from my point of view I would never use 240 volt machines if a 3 phase one was available - obviously quality of the incoming supply varies with supplier / proximity to nearest substation / if supply is overhead or underground - the list goes on - also if you use a lot of power on a single phase it will unbalance the supply & the power companies do not like this - they often do better prices per Kwh if using the same amount roughly evenly on all 3 phases rather than all on one - this applies even if you have very little 3phase equipment but can share out your 240 volt loading across the phases - only downside is the standing charge is higher.

I do have a good supply in my shop, as there are 9 potato storages on the yard, all of them with really hefty ventilation,plus grain storage etc. And I’m less than 2 miles from a substation. Like I mentioned before, I know very little about high voltage wiring, I’ll definetly do more research but it wouldn’t be hard to get 3ph at all, and I am planning to have the shop rewired in the near future, it’s all really unorganized, lots of “temporary” wiring that been temporary for about 10 years now. So If I’m redoing everything anyways, I might switch over.


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The machines on my work truck are capable of single phase or 3 phase. I use 3 phase every chance I get. Things are almost always smoother on 3ph. Just look at most machines name plates. 3ph often increases the duty cycle on the machine.

If you intend to use your shop for more than just welding, eg. also perhaps get a lathe, mill, saw or similar then it's often a lot easier to find affordable old/used industrial machines in auctions or machine dealers if you have 3 phase power as that's what they are usually designed to run with.

Bye, Arno.