Can anyone recommend the best Mig for use with generator

By Trev Date 02-02-2007 03:16

Forgot to mention. Using a Generac 7500watt generator and the Lincoln 255 wont even power up. I can hear the power supply humming, but the led's don't come on and gun doesn't feed wire. Very weird. Lincoln says this is normal and it shouldn't work. Why would they design something that can't run on a generator? Anyway, looking for options or ideas because I don't want to downgrade if I don't have to. Need the Amperage.

By Molten Metal (**)

Date 02-02-2007 23:15

I'm confused here.I have a Lincoln 215 mig and it works great plugged into my generator/Miller DX185.It is putting out 5500 watts continuous/6000 peak.I have a Coleman 5500 watt and while my Lincoln welds with it,it's dirty and weak compared to the Miller's output.I dont get why your machine wont function at all though????And Lincoln "told-you" it shouldn't work???"Lincoln".Or the place you shop at?Anyways,It should work.The quality of the generator does make a huge differance though.

By Robert C (*)

Date 02-03-2007 00:47

The 215's electronics are not as sensitive as the 255. If the machine cant draw at least 46amps at 220 or so volts the machine won't power up. That is the equivelant of 11,120 watts.

By yorkiepap (***)

Date 02-03-2007 02:13

Hey Trev,
I have to agree with Robert C as I have a Lincoln255 at work and it's set up with 60A breakers. The 255 will draw close to 60A on full load. You need more current....something like a 12K watt rated generator as a minimum, especially if you want to run any other ac tools in conjunction, like an air compressor. Need to feed the beast....Denny

By Molten Metal (**)

Date 02-03-2007 03:25

Wow...46 amps just to run.Well..there's your answer.I believe the 215 Lincoln only requires 35 amps and thats at full tilt.

By Robert C (*)

Date 02-03-2007 04:06 Edited 02-03-2007 04:10

That is correct, but the 255 is much more advanced. It is set up to protect the machine. The 215 assumes the proper input is being suplied untill it is proven wrong and shuts off.

By Molten Metal (**)

Date 02-03-2007 06:06

Thanks Robert.I love this site as I am learning so much through it.A think tank for welders.:)

By MDG Custom Weld (***)

Date 02-03-2007 15:57

I have the exact same set-up you are talking about. I run my Lincoln PM255 from my Ranger 250, but it takes 2 people to start welding. The ranger is 10kw, and must be on RUN, not auto idle. The reason the mig welder does not fire off as it should is because most mig welders when starting the arc dump to open circuit voltage on the initial short of the wire until the arc is established, then maintain the welding voltage that is set. This takes place in a fraction of a second, but in that time the generator has a big voltage drop until the governor opens up. This voltage drop causes the circuits of mig welder to shut down the output.

Here is the way around it: put the mig welder voltage setting lower than 15v, and the wire feed lower than 150. Strike an arc and let the generator rev up as the governor opens up (only a second or two needed). Now keep your arc on and have your helper bring up the voltage and wire feed to the needed parameters as you are welding. Don't go too high because around 19-20v and 350-400 wire, your generator just will not be able to keep the line voltage within in mig welders limits and it will shut off the output again.

Repeat for every weld needed.

As you can see, this is very time consuming if you are welding 25 2 inch welds, but it works!

Now, I'm running 10kw output from the generator, but for your 7.5kw generator, you will not be able to go as high, and this might not work at all. I'm not sure how many kw's it really takes to light off the mig welder.

Second option: Get a small 110v welder (if your generator has a 20a 110v circuit) and use that instead of the big welder. It is also much easier to move around than the 300+ pounds of the PM255.

Hope it works for you!
Mark