Garage to be protected by an RCD

[ash88]

Hi,

I am an industrial electrician and have been asked by a friend to do some work on their house. I would like some advice on RCD's.

I have been asked to install a light and a socket in a garden shed. I am planning to supply the shed via the garage which already has a supply from a 32a breaker (which i am going to replace with a 20a breaker) seen as though it is run in 2.5mm SWA.

The garage circuit is currently not protected via any kind of RCD / RCBO. However, somebody has previously installed an RCD next to the house consumer unit, and has routed the house sockets circuit through it.

Will the RCD previously installed for the house sockets interfere with an RCD if I put one in a 4 way consumer unit in the garage?

Cheers.

 

[valleybilly]

Cheers for the replies everyone, I was 95% sure but didnt want to install it all and then find the RCD's didnt like it.

Valleybilly, Yes the garage is a separate building to the house.

RCD protection will be needed for the supply to it then

 

[HandySparks]

RCD protection will be needed for the supply to it then

If it's SWA or surface run, the supply cable doesn't need RCD protection. Any socket outlets will.

 

[ash88]

Ok so an RCD mounted inside the house next to the consumer unit will cover the supplying cable to the garage too.

 

[GLENNSPARK]

Ok so an RCD mounted inside the house next to the consumer unit will cover the supplying cable to the garage too.

whats the earthing arrangements?

 

[ash88]

Or as it is SWA, just put an RCD C/U in the garage.

 

[Des 56]

whats the earthing arrangements?

Perhaps the message is not getting through whats the earthing arrangements

The whole thread and all the replies validity depend on the answer to the question Glenn has asked once again

 

[ipf]

By the way, what earthing arrangements ? Could be important.

edit: late Des.

 

[GLENNSPARK]

Perhaps the message is not getting through whats the earthing arrangements

The whole thread and all the replies validity depend on the answer to the question Glenn has asked once again

thank you Des....caus this is twice now i`v asked him...
i hope he hasn`t come in here asking advice...without checking first what the earthing arrangements are...
christ, its the first thing you do before anything else....

 

[Mork]

Hes not going to tell you!

 

[GLENNSPARK]

Hes not going to tell you!

probably caus he dont bloody know:censored:

 

[Stroppy]

Green & yellow, I would have thought. Same as most places....

 

[Octopus]

Ok so an RCD mounted inside the house next to the consumer unit will cover the supplying cable to the garage too.

How do you work this out then?

 

[ash88]

Ok im coming, im here, its a tn-c-s system, the main earth terminal is connected to N at the incoming fuse.

 

[ipf]

Hes not going to tell you!

A bit unfair, I feel. Glenn's probably hit the nail.

It seems to me that the OP knows what he's on about, judging from his posts.
Being from the industrial sector, it isn't unusual to find someone a bit behind on domestic installation details. He'll realize the implications with a little help, I'm sure.

 

[ash88]

Cheers ipf, thats why i mentioned my industrial experience in the first post... Need a bit of guidance