New Garage Consumer Unit

[BenSparky8]

Hi guys,

Just a quick one. I’m installing a garage board in, planning on a 6mm SWA supply coming from a 32a MCB. The DB I’m feeding from is a split load board.

My question is, what is the best way to move over the current MCBs to allow me to put in a MCB that’s not on any of the RCDs (as I just want the RCD protection inside the garage). If that makes sense?

Any advice would be much appreciated. Just trying to come up with the most logical way… Cheers

 

[brianmoooore]

Depends on the design of the existing CU. Some it's easy, some not quite so.

 

[BenSparky8]

This one is a plastic Hager I’m pretty sure

 

[JBW175]

It may be easier to split the tails and terminate the SWA into a switched fuse, and then run it out to the garage board.

 

[BenSparky8]

Yes that’s an idea. I’m guessing a lot more expensive? As the job has already been priced I was hoping for a different way.

Was also thinking maybe just have the RCD in DB1 and just a main switch in the garage?

I know it’s not ideal if it trips…

 

[pc1966]

Certainly would be better not to be on the house RCDs in case of troublesome trips later on if damp gets in somewhere in the garage, etc.

Many of the single/dual RCD boards have the busbar for non-RCD MCBs clamped in the main switch along with the L cable to feed the RCD(s), so if that is an option for your board then all you would need is a 2-prong section of the correct busbar and to shuffle the rest of the board 1 space away from the main switch.

How easy that is in practice depends!

Any photos of the inside of the existing CU?

 

[pc1966]

Was also thinking maybe just have the RCD in DB1 and just a main switch in the garage?

Most garage CUs come with the RCD anyway.

Having two in series is not ideal as if it trips ad either or both might go. However, while inconvenient it is safe.

It also has the small advantage that if a garage circuit is faulted then probably the garage RCD would go so if the person resets the house CU RCD they might get the power to stay on without having to try isolating the garage (or more importantly, knowing to try that).

 

[BenSparky8]

Hi, yes definitely agree. Unfortunately I don’t have any pictures of the inside of the board until I get to the job tomorrow. Yes that could be an option!

 

[123]

Move the lighting circuit which the main bathroom is on to the RCD side of the board and then you have a spare way on the non RCD side

 

[BenSparky8]

Yes I’ve noticed that literally all garage boards come with rcd. I would like my assessor to come and see this job and was wondering if they’d mark me down for having an RCD at both ends?

 

[BenSparky8]

Move the lighting circuit which the main bathroom is on to the RCD side of the board and then you have a spare way on the non RCD side

It’s dual RCD unfortunately

 

[buzzlightyear]

It’s dual RCD unfortunately

Any room at the Inn has they say, putting to rcd on both sides not a good idea. deigning is a key must 32amp non rcd out 64 amp rcd garage check for extraneous pipe work DNO tncs /tns/ tt.