Can a metal CU have a neutral bar?

[numpty with a crowbar]

Hey folks. Was having a look at a CU on a mobile board a few days back (owned by a mate who uses it for gigging). The CU on the board was a metalclad one, and as well as having an earth bar it had a separate bar that was being used for all the neutrals.
Now I've wired up a few small CU's in the past, and admittedly they've mostly been plastic, but I'd never seen a metal CU with a neutral bar on it before, and I was wondering if it's safe? Or has whoever wired it up originally used a 2nd earth bar as a neutral in error?? The bar itself was insulated from the metal of the CU (obviously the RCD would trip of there was a bridge between the neutral and the body of the CU - and does that answer the question re safety??). But is a neutral bar a common thing on a metal CU??

 

[Lectrician]

Of course it is It is insulated on stand offs if attached to the case. It may be part of the pan assembly on others.

How else could you safely connect all the neutrals?

 

[breezer]

agree with aboove, if it didnt where would the neutrals go?

 

[numpty with a crowbar]

Of course it is It is insulated on stand offs if attached to the case. It may be part of the pan assembly on others.

How else could you safely connect all the neutrals?

That's what I thought - but you know when a part of your brain starts questioning something, even if logic says that that it should be fine

Guess I must have been having one of those "confusion" moments. And at least I didn't make a fool of myself by saying "is that safe??" a few days back.....

Cheers

 

[numpty with a crowbar]

agree with aboove, if it didnt where would the neutrals go?

This is true - however I wired a very small CU a few years back (only had space for and RCD & an MCB) which was metal & didn't have one (but did have an earth bar) - hence the confusion... But I guess that was due to size not safety.

You live & learn...

 

[ayen]

so what did you do with the neutrals??????

 

[plugwash]

presumablly if its only got one or two breaker positions the neutral outgoing terminal on the isolator or RCD will be more than sufficant to accomodate the outgoing neutrals directly.

 

[securespark]

If it's a mobile board & run off a gen with effectively a TT set-up, then you need to ensure the supply to the metalclad board is RCD protected.

 

[numpty with a crowbar]

so what did you do with the neutrals??????

Did exactly what Plugwash said - because it was a straight ring final (4 x single 13A sockets), all there was was 2 x 2.5mm neutrals - which fitted into the RCD with no problems. Admittedly if there had been a lot of neutrals I'd have been stuffed....

Next time I'm gonna keep my gob shut...

 

[RF Lighting]

Metal clad CU with neutral bar

 

[plugwash]

looks like it has a MCB as incomer..... most unusual

is that a SPSN MCB or some form of solid neutral link? and what brand is the thing.

 

[numpty with a crowbar]

Metal clad CU with neutral bar

If you don't ask you'll never know I guess..... That's my only defense and I'm sticking to it

 

[Adam_151]

IIRC, he said they forgot to ship his isolator, so he just chucked a spare MCB and some kind of link in there so he could get his incomming tails cut down to length, etc

 

[Lectrician]

Thats a square D board - has push in type MCB's.

Made by same company as Merlin Gerin, They are identical, except merlins MCB's are not plug in.....but if you pop off the cover at the top of a square D MCB you can release the plug in part and turn it into a Merlin one.

MK are identical to Merlin.

Good boards, but prefer MEM.

Square D are white boards, and Merlin have always been moonstone grey.....but have just gone to white. Pricks - white TP boards in an industrial environment - stupid!