How to wire up garage RCD

lemonkettaz · 28 Dec 2014 at 19:14

Feeding a garage consumer unit from a spurred connection from your ring main in the house (32A) is not the way to go if you plan on all that activity potentially in your garage.

House Consumer > RCBO > SWA Cable (possibly) > Garage Consumer > RCD > then all your circuits in the garage

Lisapete · 28 Dec 2014 at 19:51

Let me get this right.

If I add an RSBO to the spear bus bar I got, and run a SWA cabl from this too the garage I'm safe and all okay?

ZG002 · 28 Dec 2014 at 19:58

You don't need a rcbo, just a mcb. The 30ma RCD protects everything to the left of your CU.

I always over spec slightly myself, but I'd be running a 4mm SWA. Running from a 32a mcb.

lemonkettaz · 28 Dec 2014 at 20:00

RCBO gives you overcurrent protection too.

RCD is just earth leakage

Lisapete · 28 Dec 2014 at 20:04

So MCB in along the busbar SWA stripped and in, earth to earth, nuteral to nuteral and then live into the MCB

ZG002 · 28 Dec 2014 at 20:04

Why the hell would you put a RCBO on the RCD protected side of his cu?.....

lemonkettaz · 28 Dec 2014 at 20:42

Yeh you don't have too

That Garage Cu is being fed via an RCD protected 32A MCB? I'd still have an RCD in the garage. The SWA from the main Cu won't need RCD protection, however once outside it will need the RCD protection from stuff after the Garage Cu.

Lisapete · 28 Dec 2014 at 21:10

So what should I fit exactly? Screwfix does a lot of Wylex which is cool as I get 20% off.

SWA cabl I found some 4mm 3 core on eBay. Watched a YouTube on how to strip/terminate it. Would go for the 3 core as this is what's currently fitted but also allow an earth. Will use color markings for it.

ZG002 · 28 Dec 2014 at 21:18

Run the SWA from your main CU, can likely reuse that box they used one your old one to terminate, then run 4mm t+e to cu.

In the cu, put a 32a Wylex MCB to the left of the outside lights mcb (if you have room). Connect into that.

Garage side just connect as you were going to.

Lisapete · 28 Dec 2014 at 21:40

ZG002 said:
Run the SWA from your main CU, can likely reuse that box they used one your old one to terminate, then run 4mm t+e to cu.

In the cu, put a 32a Wylex MCB to the left of the outside lights mcb (if you have room). Connect into that.

Garage side just connect as you were going to.

The box that the current SWA runs from too the garage is on the back of the kitchen, roughly where the oven is. The CU is in the dining room which is too the the right of the back door. The SWA is fed form 2.5 T&E but where this T&E in the kitchen runs off no idea.

http://www.screwfix.com/c/electrica...ategory=cat7230022&amprating=32_a&brand=wylex

They list 3, which should it be.

I think a new SWA run with the MCB will be better. Does the cable have too be berried?

Lumeycom · 28 Dec 2014 at 21:41

Hilarious thread...

Not that I do domestic but if I'd terminated a CU like that I'd expect the sack.

Personally I wouldn't feed the garage from the house DB. I'd rather split the tails (henly blocks), put a small 2 way DB next to the house DB for isolation and overcurrent on the SWA (unless there is something weird in part p which I know little of) there is no need for RCD protection on an armoured if its installed correctly. Be worth checking with a housebasher on that though.

Reason for not feeding out of the house DB? Simple.. nuisance tripping. any outbuilding has a significantly higher risk of actual faults and/or nuisance tripping so why risk it knocking your up front RCD out and defrosting your freezer?

Also if its a new build I'm going to take a punt that its PME (TNCS) earth supplied by the distributor. If it is and your taking a feed out of the building then you need to ensure that you meet PME rules as a minimum.

Edit - I can see exposed busbar on that last picture, I hope there is a cover for it if not remove it.

Lumeycom · 28 Dec 2014 at 21:42

Does the cable have too be berried?

http://www.tlc-direct.co.uk/Products/BK1717.html

ZG002 · 28 Dec 2014 at 21:43

The middle one, and no not needed with SWA.

ZG002 · 28 Dec 2014 at 21:47

Lumeycom said:
Hilarious thread...

We get it a lot.. Bordering on dangerous sometimes these threads.

Doing as you say is beyond the skill of the op imo. And he refuses to pay an electrician lol.

Traffic_Warden · 28 Dec 2014 at 21:50

Lumeycom said:
Hilarious thread...

Not that I do domestic but if I'd terminated a CU like that I'd expect the sack.

Edit - I can see exposed busbar on that last picture, I hope there is a cover for it if not remove it.

Not really Hilarious, the guy wants to do it himself, no one can stop him? It is possible for a un-skilled electrician to carry out electrical work. Just the same as it's possible for me to do an engine swap on a car and i'm not a mechanic? but I didn't learn how to safely hoist a engine up at college did I so I might kill myself in the proccess? Just use common sense. I am still alive and have had many cars and done all the work on them myself well.

There's nothing wrong with that C/U apart from a few of the MCB's have copper showing out of the terminal and there's not 30mm of outer sheath taken off the incoming tails to show their ID colour. That's all. Just because it's scruffy doesn't mean it's wrong in any way either.

Also, the busbar being exposed, that's not a problem, there will be blanks in the C/U cover that will stop any fingers/poking insruments getting to touch that busbar once it's on. You only commonly find busbar blanks on 3 phase C/U's where the blanks for the covers are not so solid and tend to pop off all the time and you then see the busbar through the cover.

ZG002 · 28 Dec 2014 at 21:55

Traffic_Warden said:
Also, the busbar being exposed, that's not a problem, there will be blanks in the C/U cover that will stop any fingers/poking insruments getting to touch that busbar once it's on. You only commonly find busbar blanks on 3 phase C/U's where the blanks for the covers are not so solid and tend to pop off all the time and you then see the busbar through the cover.

Don't get me wrong, I don't have a issue with it either, but I'd be surprised if that busbar didn't come with covers, all the ones I've fitted with Comb type bars have them supplied.

Traffic_Warden · 28 Dec 2014 at 21:59

Would you bet on that? haha

it's not the usual Hager/MK/Wylex/Schneider/Crabtree you would usually use, i don't even think i've came across a general british board ever, and my dad hasn't either and that's going back a few years lol

Lumeycom · 28 Dec 2014 at 21:59

Traffic_Warden said:
Not really Hilarious, the guy wants to do it himself, no one can stop him? It is possible for a un-skilled electrician to carry out electrical work. Just the same as it's possible for me to do an engine swap on a car and i'm not a mechanic? but I didn't learn how to safely hoist a engine up at college did I so I might kill myself in the proccess? Just use common sense. I am still alive and have had many cars and done all the work on them myself well.

There's nothing wrong with that C/U apart from a few of the MCB's have copper showing out of the terminal and there's not 30mm of outer sheath taken off the incoming tails to show their ID colour. That's all. Just because it's scruffy doesn't mean it's wrong in any way either.

Also, the busbar being exposed, that's not a problem, there will be blanks in the C/U cover that will stop any fingers/poking insruments getting to touch that busbar once it's on. You only commonly find busbar blanks on 3 phase C/U's where the blanks for the covers are not so solid and tend to pop off all the time and you then see the busbar through the cover.

Changing an engine on a car does not require a notification to the local authorities and retrospective planning permission does it? Part P of the building regs says what this person doing does. As much as that sucks its the letter of the law. It IS notifiable work.

Busbar's missing internal covers are clear Code 2's on the current amendment for EICR's and it is not an acceptable deviation on an Installation Cert. Doesn't matter how many phases it is or is not (Also I don't think I've ever come across a TP+N consumer unit)

I've no issue with DIY'ers, I make quite a bit of hobble money cleaning their mess up

Edit - just noticed you do my job offshore, curious comments for an ex spark :E

Traffic_Warden · 28 Dec 2014 at 22:09

My brother is the offshore spark

don't hold him for anything I have said above lol, i am the house basher we just use the same account

I will look up this busbar lark...but i find c2 for that a bit harsh...but i'll do some research

*

also, i don't know the OP's location, up here we don't follow part p so I should have left most of what I put out if he is installing this under part p locations in the UK

Lisapete · 28 Dec 2014 at 22:15

Thank you to all that have properly taken time to help.

I ow you a beer and more comment but I've sank a few of them so far.

I have someone that can sign it all off once he has checked it. He is not willing too take time to do it or show me how. Sometimes that line in the sand has too be drawn.

Why not try your hand at it. The cost quotes I've ben given do not touch what it's cost me for me to do it on parts along. Mark up and half.

I could wired it up by now but chose not and to listen too your advice.

Them that can only rip everything and anything someone says or does your not welcome here.