Advice on what consumer unit to fit

[Mikey10695]

Hi ive been recently asked to wire a large property which has been specified to require 13 circuits
2 x 6amps
5 x 32amps
2 x 20amps
2 x 16amps
2 x 40 amps

Im just wanting some advice on consumer units, rcd and main fuse sizes

A 14 way consumer unit dual rcd would be ideal but im wondering how it works with rcd amperage, im aware each side of the board should be balanced out but should the amperage of each mcb total the amerage for the rcds?

 

[telectrix]

look at the SBS CUs. aLL RCBO. no floppy links . RCBOs. loads of room to dress cables. a sparks dream machine.

 

[Dartlec]

Hi ive been recently asked to wire a large property which has been specified to require 13 circuits
2 x 6amps
5 x 32amps
2 x 20amps
2 x 16amps
2 x 40 amps

Im just wanting some advice on consumer units, rcd and main fuse sizes

A 14 way consumer unit dual rcd would be ideal but im wondering how it works with rcd amperage, im aware each side of the board should be balanced out but should the amperage of each mcb total the amerage for the rcds?

You might be better checking the loads, because even in a large property they could never use those loads on a standard 100A supply (nor would they ever get close to it I suspect). Are the 40As showers or hobs?

If there are lots of large loads, multiple showers etc that could be genuine regular loads then you may need to consider whether the main fuse is adequate.

RCBOs are probably better - if it's a large property then there should be something in the budget for a decent board that will last...

If they are really being tight, then maybe a Dual RCD Hi Integrity board, with RCBOs on some selected circuits...

 

[Mikey10695]

look at the SBS CUs. aLL RCBO. no floppy links . RCBOs. loads of room to dress cables. a sparks dream machine.
View attachment 84374

Now thats what im talking about ????

 

[Dartlec]

look at the SBS CUs. aLL RCBO. no floppy links . RCBOs. loads of room to dress cables. a sparks dream machine.
View attachment 84374

what's between the busbars? just a bit of plastic? It would take me ages because I'd be having to constantly check I hadn't got one of the prongs the wrong side of the screw clamp.

Looks like it would be a dream to EICR though!

 

[Mikey10695]

You might be better checking the loads, because even in a large property they could never use those loads on a standard 100A supply (nor would they ever get close to it I suspect). Are the 40As showers or hobs?

If there are lots of large loads, multiple showers etc that could be genuine regular loads then you may need to consider whether the main fuse is adequate.

RCBOs are probably better - if it's a large property then there should be something in the budget for a decent board that will last...

If they are really being tight, then maybe a Dual RCD Hi Integrity board, with RCBOs on some selected circuits...

Both 40amps are showers, do you think it would be better to get them to bite the bullet and go for a 14 way rcbo board?

 

[Mikey10695]

Both 40amps are showers, do you think it would be better to get them to bite the bullet and go for a 14 way rcbo board?

I believe 2 of tge 32amps are cooker and hob

 

[Soi disant]

Both 40amps are showers,

Nothing to prevent them being used simultaneously?

 

[Soi disant]

what's between the busbars? just a bit of plastic? It would take me ages because I'd be having to constantly check I hadn't got one of the prongs the wrong side of the screw clamp.

These people are supposed to be specialist custom DB builders.

Surely they don't use 2 individual SP busbars for DP devices? It's not as if DP ones for single-module DP devices don't exist...

 

[Dartlec]

I'd personally say RCBOs are definitely the way to go - Fusebox are cheap enough to not get silly, and even the Hager ones aren't outrageous compared to what's being spent elsewhere I'm sure.

Type A RCBOs should mean it's not going to need any upgrading for a long while - until AFDDs are more widespread...

But that does sound a lot of load for a (I assume single phase ) fuse head, if those showers might both be used at once...

If there's ever likely to be additions (more than one EV for example), then might be worth investigating a Three Phase head.

You can get devices to mitigate overload with showers - where it won't let both draw 40A at once... David Savery has a video on it on youtube....