Split phase confusion

[Af123]

Hi guys I have recently bought a nexus nxm 300 mig welder and it is fitted with a 5 pin 3 phase plug however only 2 of the phase pins are being used and after opening the top of the machine I noticed that it says it can run on 220 volts rather than 415 you get with 3 phase,I have discovered it is called split phase? and was wondering if there is any way I can run it to regular uk single phase power ?

 

[Bornfree]

Looks like it's 3ph only to me.

 

[Erie Fred]

Does the UK even have split phase ?

 

[Gareth J]

Does the UK even have split phase ?

Yes.

But I'm not sure it's relevant to this welder that looks to be explicit in that it wants three phase.

UK split phase is two nominal 230V phases 180deg apart with a shared neutral. So, either 2x normal single phases, or one big single phase @~460V. If I understand it correctly.

Aside from giving a more capacity than a single, single phase, without running so many cables to a property, it's almost completely useless. I've got one old motor that's rated for 460v single phase, but I don't know if anyone makes stuff like it now. Even that I run on 230V anyway.

 

[GRW]

Looks like it's able to operate on 3ph only, its just that it can operate on 220v 3ph (USA???), 380v (Europe) or 415 (old UK std).
There did used to be welding sets that were sold as being able to use either 1ph or 3ph.... but these weren't true 3ph machines (they used either 2 phases of the 3ph supply only, both of a Split Phase supply, or reconfigured to just use single phase).
It states on the plate it requires the correct cable size for the voltage, but needs 3 Lives plus Earth (old set so no Neutral connection).

G.

 

[chrismac]

Does the UK even have split phase ?

The farm down the road from me has it, its very expensive I was told to get motors rewound when they fail, the equipment it was used for is now obsolete and due to the motors burning out and not getting replaced it is now just more like a museum!

 

[GRW]

The farm down the road from me has it, its very expensive I was told to get motors rewound when they fail, the equipment it was used for is now obsolete and due to the motors burning out and not getting replaced it is now just more like a museum!

Most places now I think just use single ph motors off each leg, like you would off a 3ph supply for 1ph stuff.
I came across many farms with 2 phases, but none that still ran any 460/480v split phase motors.

(I was spec-ing for backup generators, so as long as no 2ph stuff, I was Ble to spec a single phase generator, via 2 fused outlets, via a 4-pole c/o switch. This got around the inevitable large phase imbalance on a farm, and kept things simple)

 

[mark roberts]

I think you are maybe getting confused when you saw 220v and assuming it means single phase. When it actually means just 3 phase but at low voltage

 

[hotponyshoes]

There did used to be welding sets that were sold as being able to use either 1ph or 3ph.... but these weren't true 3ph machines (they used either 2 phases of the 3ph supply only, both of a Split Phase supply, or reconfigured to just use single phase).
It states on the plate it requires the correct cable size for the voltage, but needs 3 Lives plus Earth (old set so no Neutral connection).

G.

New ones are still available now, Miller, Esab, etc.

They are better than the old ones as they use auto-switching. So you can fit the machine with a 3ph plug then just use a simple 1ph plug-3ph socket adapter if you want to use then on a different power supply

Very handy for mobile welding.

 

[Dave-sparks]

Does the UK even have split phase ?

Yes, its fairly common in remote and rural areas for various reasons.

But it's not commonly available everywhere and not often installed these days.

There's also a few other odd historical supplies around such as true 2 phase supplies (2 phases 90degrees apart)

 

[Erie Fred]

Yes, its fairly common in remote and rural areas for various reasons.

But it's not commonly available everywhere and not often installed these days.

There's also a few other odd historical supplies around such as true 2 phase supplies (2 phases 90degrees apart)

Thank you for this.


Real 2 phase, while never common here, it's still around Buffalo NY I have heard.

 

[8ob]

My old esab ran off two phases and a neutral, always assumed the neutral was needed for the solenoids/contactors. When I asked on here a while back the general consensus was it is still regarded as a three phase set.

Bob

 

[eddie49]

Hi guys I have recently bought a nexus nxm 300 mig welder and it is fitted with a 5 pin 3 phase plug however only 2 of the phase pins are being used and after opening the top of the machine I noticed that it says it can run on 220 volts rather than 415 you get with 3 phase,I have discovered it is called split phase? and was wondering if there is any way I can run it to regular uk single phase power ?

It is not called split phase.
As shown on the voltage selection label and on the dataplate, the welder can run on a 220, 380, or 415 volt supply, but with all three options there is an indication that three phases are needed.
On the internal photo in this thread:

Nexus NXM 300 Flashing

Hello I'm new here but could really do with some expert help. I have been asked to looked at a friends nexus NXM 300 mig set. The fault was unknown to us both but just told it wasnt working, possibly overheating. You can power the set up but as soon as you press the trigger on the gun it sparks...

www.mig-welding.co.uk

you can just make out that the main transformer has three coils or "legs", and that layout of transformer core will only work correctly when supplied with three phases that are 120 degrees apart.
If only two of the three phase pins in your 5-pin "red" plug are connected to the power cable of the welder, that is a mistake.

 

[brightspark]

still see a few 415 volt single phase motors on farms in the sticks. mainly on mills and milking machines round about 5hp

 

[Af123]

Thankyou everyone for the help I have decided I am going to sell the welder and buy a single phase mig welder instead

 

[Dave-sparks]

Thank you for this.


Real 2 phase, while never common here, it's still around Buffalo NY I have heard.

We also have a very odd and peculiarly British phase/anti-phase system in a few areas which was developed to allow AC distribution to be used with the original 3-wire DC distribution cables.

 

[Dave-sparks]

still see a few 415 volt single phase motors on farms in the sticks. mainly on mills and milking machines round about 5hp

That's an interesting one, I haven't encountered that before.
Is that 415 wrt earth or something else?

Which part of the country is that in? I'd be interested in researching the history of that one.