CU labeling

[very_pointy_ears]

Hi,

I've replaced my CU with a 17 way Wylex split load and notice that there are some numbered sticky labels that came with it. The note said that they're to be stuck on each breaker.

What are the rules regarding this?

If I put number 12 on a particular breaker, does this mean that the earth for that circuit is meant to be in the earth bar terminal number 12 and similar for the neutral? I can't see how this would be possible in my unit because although the earth bar has terminals labelled 1 to 17 plus a few others for the MET the two neutral bars have 1 - 12 and 1 - 15, ie none numbered 16 and 17.

I've made the connections in the same order as the MCBs are in and have labelled each breaker on the outside cover but so far no labelling inside.

 

[luminaire]

They are supposed to be numbered in sequence for the RCD and non-RCD circuits.

 

[very_pointy_ears]

Hi,

Thanks for your answer but I only partly get it.

If I had 8 ways on non-RCD and 9 ways on RCD, I can label the one next to the main switch as 1, put it in the non-RCD neutral bar at position 1 and connect the earth to position 1 on the earth bar. I could then carry on up to 8 like this.

On the RCD side, I'd be using stickers 9 - 17. I could start off by putting the first one into connection 9 on the RCD neutral bar and the earth in connection 9 on the earth bar, but seeing as the RCD neutral bar only goes up to 15 I'd be stuck where to connect the last ones.

What would most people do?

 

[plugwash]

I would put the first RCD circuit in position 1 on the RCD side neutral bar.

 

[JohnD]

I would throw away stickers 16 and 17

I would start wiring the RCD side at position 15 and work towards the lower numbers

I would start wiring the non-RCD side at 1 and work towards the higher numbers

When you have fitted the main switch and the RCD, how many usable ways do you have left for MCBs?

 

[very_pointy_ears]

With the main switch and RCD fitted, there are still 17 usable ways ...

 

[JohnD]

that's a fine big one you have.

Not as big as mine, obviously

 

[very_pointy_ears]

that's a fine big one you have.

Not as big as mine, obviously

I bet your dad's bigger than my dad too ...

 

[Lectrician]

As far as the regs go, the neutral of the corresponding phase must be in the same numbered terminal - The MCB's are not usually numbered, but run 1, 2, 3, 4, 5 from main swith (left to right), and on many boards, 11, 12, 13, 14 etc from the RCD (right to left). The neutrals and earth bars are numbered to match this.

You are meant to stick the crappy stickers to the MCB's as supplied, but people rarely do.

The earths would be nice in the correct order, but as far as the regs go, they actually do not have to be.




For anyone flitting through - I am speaking of the stickers with numbers on for the MCB's, not the circuit ident stickers.

 

[RF Lighting]

 

[Lectrician]

Is that one of yours RF?

Not keen on the concave washers


Prefer to see the mains tails not being turned so tightly against the brass bush


Nice and neat though

 

[JohnD]

looks like somebody got a numbering machine for Christmas

 

[RF Lighting]

The design of those KQ boards makes it difficult to keep the washers flat.

The tails are not tight, that's a 32mm bush, with 3no. 16.0mm² singles coming through it. All the outgoing circuit wiring passes through the other bush.

If thats the worst you can think of, then I'm happy

It's my tyco labeling machine. It prints heat shrink for cable numbering.

 

[Lectrician]

Im happy too

 

[Taylortwocities]

Very tidy, and thanks - you've reminded me why I hate Square D