3 phase supply 4 pin vs 5 pin.

[rjsharpy]

Hi all, For the last year i'v'e been renting a shed with 240v. Max supply currently is 20 amp although I run a 240v Mig and Arc welder on 16amp plugs and cable.

I do have three phase motors, compressors and mill which I can't run at present. However i'm going to run a 30meter 415v supply from a nearby power house (each phase has a 60 amp fuse and an earth). I've recntly bought quite a fwe Larger mig and Tig welders at auction but all these have 5 pin plugs and therefore an additional neutral core.

I will be getting 32AMP armoured cable 4mm core for this extension and onl running once device ant any one time. However can I run the five pin welders when I only have a four core supply and no Neutral? Can I make an adaptor which put the nutral of the welder to the earth also?

Cheers Rich

 

[madkayaker]

Don't take this wrong but I don't think you should be working on three phase if you need to ask that!

If there is currently a neutral where your bringing supply from then run it in to the new shed If there isn't its a fairly big job to make one running it to earth is a big no no in this country unless your the electric board!

It can be done with a transformer but its quite a special piece of kit and price

 

[madkayaker]

It is worth checking though if any welder your getting needs a neutral though as many sets get a five pin plug even though there not used to keep plugs standard across sites etc

 

[awemawson]

Do the welders with the 5th pin actually use it? It will usually only be used if there is 240v stuff in it such as fans or motors, but even then they may be powered from a transformer tapping within the welder. A lot of 3 phase wiring is only 4 core ie 3p +e

Having said that I've wired my shop entirely in 5 core, as it is very useful to have a 13a socket on a lathe, mill etc for extras such as dro's lights etc. (choose the same phase as your 13a ring main so that there is no danger of 415v socket to socket)

 

[Feanor]

Within the last 12 months I've fitted new red commando-type plugs to a 3 phase Cebora MIG welder and 2 TIG welders. None of them had a separate neutral, just the 3 phases and earth. Check within your plugs to see what's in there. If there is no Neutral then the cheapest option would be to swap the machines to 4 pin plugs and buy 4 pin sockets to suit. Having said that .....

Why will you not have a Neutral anyway? Is there none at the source you are taking from? If not - why? How modern is it? Is it in use otherwise? Does it look ropey?

PS: I'm not an electrician. Always get good advice if not sure.

 

[brightspark]

Within the last 12 months I've fitted new red commando-type plugs to a 3 phase Cebora MIG welder and 2 TIG welders. None of them had a separate neutral, just the 3 phases and earth. Check within your plugs to see what's in there. If there is no Neutral then the cheapest option would be to swap the machines to 4 pin plugs and buy 4 pin sockets to suit. Having said that .....

Why will you not have a Neutral anyway? Is there none at the source you are taking from? If not - why? How modern is it? Is it in use otherwise? Does it look ropey?

PS: I'm not an electrician. Always get good advice if not sure.

the reason for running just the 3 lives and earth is cost running the extra core in armoured and singles. it makes a difrence in price . run a ringmain round a factory feeding the machines is more costly on cable and more work

 

[Hitch]

All our machines run on a 4 pin setup.

Remember to take the adaptor lead when taking one to site

 

[Feanor]

the reason for running just the 3 lives and earth is cost running the extra core in armoured and singles. it makes a difrence in price . run a ringmain round a factory feeding the machines is more costly on cable and more work

Like I said, I'm not an electrician, but why skimp on cost with something so potentially dangerous? What I do know is that I have 4 wires entering the property, plus a solid earth. Each of these is fused @ 100 amp - that's the 3 phases and the neutral. Looks and sounds good to me.

I understand costs are always an issue and wiring can be eye-wateringly expensive. With 3 x 60 amp as the OP mentioned, I would want it to be done properly.

 

[madkayaker]

It's not an issues if there is no need for it.


Fr a big cable run and machine the cost difference can be very big.

 

[brightspark]

Like I said, I'm not an electrician, but why skimp on cost with something so potentially dangerous? What I do know is that I have 4 wires entering the property, plus a solid earth. Each of these is fused @ 100 amp - that's the 3 phases and the neutral. Looks and sounds good to me.

I understand costs are always an issue and wiring can be eye-wateringly expensive. With 3 x 60 amp as the OP mentioned, I would want it to be done properly.

how do u work that out u would want it doing properly ??why use a 4 core cable when the machines only need a 3 core , u get what you pay for and nothing else . if the punter wants to pay more and have the 5 pin sockets thats up to them . there given the option

 

[Feanor]

how do u work that out u would want it doing properly ??why use a 4 core cable when the machines only need a 3 core , u get what you pay for and nothing else . if the punter wants to pay more and have the 5 pin sockets thats up to them . there given the option

Crikey, why do I get the feeling it's becoming confrontational and certain people are on the foothills of an argument?

Maybe I shouldn't have used the word 'properly' as if to suggest the chap is going to do it improperly ...... which is obviously ridiculous because anyone reading what I wrote will see that's not what I meant ......... unless they wish to see it that is.

What I meant anyway was the supply coming into the unit. I would feel better if it was five wires than four, if that's at all possible. It's only my thoughts on the matter and I did state twice I'm not an electrician. Maybe I'm totally wrong.

I've had a four-wire and earth @ 80 amps per phase coming into the premises for the 26 years I've been there and I've done some wiring, had electricians in doing more and new meter and tails from the power company in that time. Fitted a few plugs too. I've also asked questions along the way - as you do. As a result I know a little tiny bit about it, rather than sod all. Maybe not as much as you of course, but I was only trying to give what advice I could to someone who asked. And of course he could fit four or five pin plugs as preferred - I'm sure he will know that by now too.

As you say, you get what you pay for. So if he only pays for 3 phases and earth that's all he will get. If he pays more he will get more - a dedicated neutral in fact. Kind of proves my point. Of course he may not want to, etc, etc.

I'll get me coat......

 

[dannyp]

if you have a nuteral at the distrobution board i personaly would take it.

that way you allways have the nuteral avalible if needed but you don't have to use it, if its not there you cant use it

there is no saftey differance with 4 or 5 pin it's still 415 V across phases and it's still got an eath

if you end up runnign lights the nuteral becomes more usefull idealy with 3 phase tho evenwhen you have a nuteral it shouldn't be needed as teh loading on all phases should be balance and jobs a good one when you phase loading isn't balanced the nuteral is needed tho

 

[madkayaker]

I think we're straying from the op. it sounds like to me the supply he is wanting to tag onto has been run in for some kind of plant (maybe disused) that may not have a neutral and he is trying to find out if he needs one. (Big old factory also used to get away with running to earth if they had there own hv)

As has already been said if its a true three phase welder there is good chance no neutral needed but any 230v kit will need one.

 

[Exuptoy]

It all depends on the supply authorities feed. In the uk we have , TT, TNS, TNCS Etc, they are all dependant on what is fed into the property. Most of the time the SA will split down the incoming neutral to neutral earth or even specify a ground rod at the property (TT system). It is all down to them you need to ring them and ask.

The machines will more likely be 3 ph and e and will not need a neutral, however this means you will have no neutral at the property for single phase kit.

 

[Exuptoy]

For the benefit of a certain electrical "expert" on here, I will try to explain the TN-C-S system below.

Usually a property in the UK may be fed by a TN-S system (by far the most common), with separate neutral and protective conductors (even though the star point at the supply authority transformer will be both neutral AND earth), BUT, the SA may use a common conductor for both the neutral and the earth. This combined earth and neutral system is sometimes called the protective and neutral conductor (PEN) or the combined neutral and earth conductor (CNE). The system is most usually called the protective multiple earth (PME) system, officially called the TN-C-S. Now if you were a spark, you'd have probably heard of these terms!!!

 

[astro_al]

I'm no electrician, but what I've done twice now, and would do again, is a full 5 core set up, 3P, N & E. that way you're all set for whatever you might need. Do it once, do it right.

Then any 4 pin tools (of which you'll have lots) just don't use the 5th pin (neutral) in the plug. Simple.

Al.

 

[Exuptoy]

I'm no electrician, but what I've done twice now, and would do again, is a full 5 core set up, 3P, N & E. that way you're all set for whatever you might need. Do it once, do it right.

Then any 4 pin tools (of which you'll have lots) just don't use the 5th pin (neutral) in the plug. Simple.

Al.

If you have the option, this is the way to go.

 

[Robotstar5]

For the benefit of a certain electrical "expert" on here, I will try to explain the TN-C-S system below.

Usually a property in the UK may be fed by a TN-S system (by far the most common), with separate neutral and protective conductors (even though the star point at the supply authority transformer will be both neutral AND earth), BUT, the SA may use a common conductor for both the neutral and the earth. This combined earth and neutral system is sometimes called the protective and neutral conductor (PEN) or the combined neutral and earth conductor (CNE). The system is most usually called the protective multiple earth (PME) system, officially called the TN-C-S. Now if you were a spark, you'd have probably heard of these terms!!!

Yes, I'm a spark and I have heard of those terms unfortunantely, the way you've written the explanation even confused me!
Try splitting it into seperate paragraphs for TN-C-S & TN-S also add one about TT for the rural members?
Maybe add a link to Wiki explanantion

 

[Exuptoy]

Yes, I'm a spark and I have heard of those terms unfortunantely, the way you've written the explanation even confused me!
Try splitting it into seperate paragraphs for TN-C-S & TN-S also add one about TT for the rural members?
Maybe add a link to Wiki explanantion

Haha, yeah cheers dude. I sometimes know what I wanna say but getting it down in writing for others to read in layman's terms is another thing. Also writing it when you're p***ed off because someone has slighted you is another no-no, and all because I had missed out the word NOT!

I work offshore and we have our own generation with 2 x 4.69 MW gas/diesel turbines producing 6.6KV with a prospective short circuit current of 1250 amps and being distributed onto 6.6/415 transformers feeding numerous boards and also at times synchronising onto 2 marine diesel generators and an emergency generator, MOD ****** No slagging off please!**********

 

[Wozzaaah]

Cut the willy waggling please!
You're always going to get differences of opinions on forums but insulting members is likely to get you a spell in the sin bin.
That goes for anyone, regardless of how long they've been a member.