Thread: Inverter welder power supply

If it has a 15amp plug then it should be ok in a 15amp power outlet.

The one that runs 32amp is a 3 phase setup and isn't compatible with a normal 240v power point in 10amp or 15amp spec.

There are a few derivatives of the 3 phase plug, but they are variations of this:

I've got a single phase BOC 250A MIG (which is a Kemppi inside) running from a 15A socket on a 16A fuse, and I've never tripped it out, even on relatively heavy steel sections, but I am an intermittent welder, maybe 3 or 4 minutes use at a time.

I am just looking at a 3 phase pulsed MIG, and have discovered that there are 20A and 32A sockets (like the one Slunnie posted above) and they are not interchangable. Just the 3-phase power box & switch for the wall was over $200, so a lot more expensive than normal 15A sockets.

Is the UniMig 250 a 3 phase welder?

As an industrial maintenance electrician, I have come across this problem a few times. One had been usint this MIG for about 2 years without a problem on the 15A plug, The issue came about when trying to weld continuously for more than 10 minutes on 10mm plus plate over 3m long, the current draw far exceeds the ability of the supply and more importantly the protection device from tripping. Basically the welder will draw what it needs to feed the output.

We have overcome this by fitting out with a standard 32A, welder runs max 30Aish, 5 pin plug and wired for single phase, this allows for use anywhere with standard outlets.

The circuit breakers only use in life is to protect the fixed wiring in in the installation, doesnt matter what you plug in! doesnt care!

If you do have 20A protection and a 15A outlet, I would be more concerned with what sized cable is feeding the outlet and what it is run through, the biggest problem with running high current through cable is the dissapation of the heat, generally only rated to 65degC.

If you are only welding light guage material and in short runs, not a problem, rely on the breaker for your run time and work accordingly, If you do want to be more commercial with your setup, rewire and be safe you wont burn your shed down.

Originally Posted by spudboy

I've got a single phase BOC 250A MIG (which is a Kemppi inside) running from a 15A socket on a 16A fuse, and I've never tripped it out, even on relatively heavy steel sections, but I am an intermittent welder, maybe 3 or 4 minutes use at a time.

I am just looking at a 3 phase pulsed MIG, and have discovered that there are 20A and 32A sockets (like the one Slunnie posted above) and they are not interchangable. Just the 3-phase power box & switch for the wall was over $200, so a lot more expensive than normal 15A sockets.

Is the UniMig 250 a 3 phase welder?

I'm in a similar usage situation, and definitely cant see myself doing long runs of heavy material.

The UniMig is definitely a single phase one.

Out of interest I also had a look at the specs on the CIG 250i as a comparison to the UniMig.
They actually list 2 different specs depending on the lead that is fitted to the welder (independent of the fixed supply).
If the factory fitted 15A(2.5mm2) cable and plug are used the welder is only capable of 190A output, but if an upgraded 25A(4mm2) cable and plug?? are fitted it will do the full 250A.

If other inverter welders behave in a similar manner then it makes sense to me that the Unimig 250 should be OK with the 15A plug but simply have lower output.

Mark_coffey - I take your point about the wiring to the socket itself. Will check out what cable has actually been used. Its only about a 4m run, and I know some of it is in conduit.

Steve

Originally Posted by mark_coffey

As an industrial maintenance electrician, I have come across this problem a few times. One had been usint this MIG for about 2 years without a problem on the 15A plug, The issue came about when trying to weld continuously for more than 10 minutes on 10mm plus plate over 3m long, the current draw far exceeds the ability of the supply and more importantly the protection device from tripping. Basically the welder will draw what it needs to feed the output.

We have overcome this by fitting out with a standard 32A, welder runs max 30Aish, 5 pin plug and wired for single phase, this allows for use anywhere with standard outlets.

The circuit breakers only use in life is to protect the fixed wiring in in the installation, doesnt matter what you plug in! doesnt care!

If you do have 20A protection and a 15A outlet, I would be more concerned with what sized cable is feeding the outlet and what it is run through, the biggest problem with running high current through cable is the dissapation of the heat, generally only rated to 65degC.

If you are only welding light guage material and in short runs, not a problem, rely on the breaker for your run time and work accordingly, If you do want to be more commercial with your setup, rewire and be safe you wont burn your shed down.

Bit confused here, but isn't 3 Phase power rated @ 415 volts and requires a 415 volt supply to the property? Regards Frank.