wylex nhtn6mr to feed single phase c/u

[crow11]

been to look at a job today, i don't normally have anything to do with 3 phase so don't shout at me to much, customer as just moved into a unit which as the above distribution board in supplying power to the original sockets, lights and alarm system, he as put the first fix in himself for some new circuits consisting of 2 new ring mains in t&e 32A each which is in 20mm plastic conduit, 2 new ring mains in swa feeding 16A sockets for welding equipment 32A each and a new lighting circuit for the welding booths and office 6A, now for some reason he wanted them on his own single phase c/u even though there are enough free ways in the original panel, so he as cut all his wires to where he wants to put his new c/u so are all about 3ft short to reach the original board, i went originally just to price up for 2nd fix and the electrician who looks after the units was going to connect the single phase c/u to the wylex distribution board, but he rang me back and said landlord as said for me to connect up, as i said above i don't do 3phase but i know you have to balance the loads which i can't see how that can be done if he wants to take a phase from the wylex board to a single phase c/u, plus with all his equipment he is wanting to plug into his new circuits he is going to have alot of tripping problems i know at this moment in time he as a welder which is 16A 1 which is 13A a 3.1kw water heater he mentioned another welder but hasn't got it yet plus whatever he going to plugging into the new sockets, as i said i don't do 3 phase so might be totally wrong lol cheers

 

[not clever]

Quote to extend the short circuit tails to the tpn board.

 

[davethsparky]

Someone's put the wrong breaker in that board!

You say you have 2 x ring circuits feeding 16amp sockets and plan to put them on a 32amp MCB, are you sure this is a good idea?

 

[crow11]

apparently his mate is an electrician who told him what cables he needed to run and for some reason won,t go back lol, the full set up is not a good idea, first thing I asked him was why din't he run the cables to the original board and he just said he wanted them on his own c/u, he says he will only ever have 1 welder on at a time but we have all heard that before, there are 4 x 16A sockets on one ring done in 2.5 swa and 2 on another which will be on 2 separate 32A mcb's, advised him about tripping issues but adamant will ever only have 1 on at a time

 

[telectrix]

maybe the spark who won't go back realises that the guy's a muppet and wants it installed in a stupid way. quote him for doing it right ( extend cables to 3 phase DB and balance the load ). if he don't like it, let him get some idiot to do it.

 

[Brightspark2]

As above if he doesn't want it done the right way then don't bother with it.

It will only come back to you, he will just blame you and deny everything. Seen it all before...

 

[Guest111]

That job is potentially a very large can of worms,put the tin opener back in your pocket and walk away,cause you sure as hell don't want to be the one who opens it!

 

[davethsparky]

16amp socket 32amp mcb, the problem should be obvious!
That game only works for 13amp plugs because they have a fuse in them.

 

[crow11]

cheers davethsparky, you know sometimes if you had hair it should be blonde well that's me at the mo lol, think its best for everyone if I stick to domestic, like I said in the first post don't do 3 phase totally didn't see the obvious, never come across a 16A socket yet on domestic but if I did I would of seen the obvious, thoughts where more on the 3 phase to single phase issue's for balancing than design no excuse I know, going to let the job go, had quite a few phone calls for 3 phase and always refuse them, only looked at this cause its round the corner, just out of curiosity does any know of any kind of training courses for 3 phase I know you need the experience as well which I don't have but would be good just to know cheers

 

[davethsparky]

Fill out your profile's basic info section including the bit about your qualifications and you might just stem the tide of 'I learned it in my apprenticeship' comments. I normally would join in but i'm in a good mood this evening.