I Seek Experienced Help!

[Diesel]

Hi, recently upgraded a garage roughly 35m from the house, have wired it with 2.5mm twin core and earth throughout and have got two circuits, a lighting circuit and a ring main, ring main, the two circuits are fed from a 32 amp MCB and a 16amp MCB which is in a small consumer unit inside the shed, I am planning on connecting a 6mm SWA Cable from the a 40amp MCB in the consumer unit in the house, outside, underground and into the consumer unit in the shed, a colleague who I would say considers himself smarter than he is, has said to me that I have done it wrong because I have to fit an RCD, my setup is not perfect but as far as I know have I done it correctly as far as....informing the owners of the house but that is my problem....I have absoloutly no experience in wiring up installations other than college work, How do I wire up an RCD, does it go after the circuit breaker, so id have the 40 amp mcb, then an rcd and then the cable leaving the house to go outside? also, there are RCD's in the consumer unit in the house, if they are there do I need to add an additional RCD? your support will be greatly appreciated.

Cheers -- CC

 

[Pete999]

Hi, recently upgraded a garage roughly 35m from the house, have wired it with 2.5mm twin core and earth throughout and have got two circuits, a lighting circuit and a ring main, ring main, the two circuits are fed from a 32 amp MCB and a 16amp MCB which is in a small consumer unit inside the shed, I am planning on connecting a 6mm SWA Cable from the a 40amp MCB in the consumer unit in the house, outside, underground and into the consumer unit in the shed, a colleague who I would say considers himself smarter than he is, has said to me that I have done it wrong because I have to fit an RCD, my setup is not perfect but as far as I know have I done it correctly as far as....informing the owners of the house but that is my problem....I have absoloutly no experience in wiring up installations other than college work, How do I wire up an RCD, does it go after the circuit breaker, so id have the 40 amp mcb, then an rcd and then the cable leaving the house to go outside? also, there are RCD's in the consumer unit in the house, if they are there do I need to add an additional RCD? your support will be greatly appreciated.

Cheers -- CC

Do you have an RCD within the CU in the house?

 

[telectrix]

ideally, the SWA needs to be fed from a non-RCD way in the house CU. you'd then install a "garage board" in the garage, RCD as main switch and the 2 or 3 MCBs as required. from you post, however, i don't think you have enough experience to design a safe, reliable installation here. where are you based, as one of us may be close enough to help.

 

[Leesparkykent]

What earthing arrangement is the supply?

 

[Diesel]

There are two RCD in the house board but I'm unsure of how they are or how to set it up, everything is earthed in the garage and house, have yet to fit this swa cable to supply the shed but was planning on using a glancing kit with banjo and as for my lack of experience, I won't be turning it on until I have had a qualified electricians to have a look

 

[Leesparkykent]

There are two RCD in the house board but I'm unsure of how they are or how to set it up, everything is earthed in the garage and house, have yet to fit this swa cable to supply the shed but was planning on using a glancing kit with banjo and as for my lack of experience, I won't be turning it on until I have had a qualified electricians to have a look

As its a new circuit this is notifiable to your local authority building control. There are lots of things that could influence this installation and not just a case of connecting 3 wires....If it was this simple then we wouldn't have to go to college for a number of years to become qualified. You admit yourself that you lack experience and no disrespect indented its obvious from what you've posted so far. I think the best advice anyone can give is to get a qualified electrician in. You may be able to do some of the donkey work to reduce the cost. For anyone to advise further would be foolish. I hope you take the advice given as electricity can kill in a fraction of a second.

 

[Diesel]

No doubt Lee but Im not exactly in a position to pay someone for £500s worth of work, I myself have found college to be next to useless due to no actual work experience in relation to electrical work, as I have said, any advice given here will be greatly appreciated and it will not be turned on until it has been checked by a qualified electrican, I am doing this not only to save money but to gain needed experience.

 

[Leesparkykent]

No doubt Lee but Im not exactly in a position to pay someone for £500s worth of work, I myself have found college to be next to useless due to no actual work experience in relation to electrical work, as I have said, any advice given here will be greatly appreciated and it will not be turned on until it has been checked by a qualified electrican, I am doing this not only to save money but to gain needed experience.

Okay but with all due respect you should be doing this along side a qualified electrician to gain experience. If you have a qualified electrician to check the work cant he give a few hours of his time to show you? Out of interest why did you wire the lights in 2.5mm T&E? Also why did you select a 16A circuit breaker for this circuit? I'm not saying its wrong just not standard practise in domestic installations. I doubt connecting an SWA is going to cost £500 if you've dug the trench etc and even laid the cable and left it open for the electrician to inspect before he connects the cable. Where about in the country are you?

Reading the OP again it also looks as this is for a paying customer? If this is true are they aware about the lack of training, qualifications and experience? Would you consider this fair?

 

[Diesel]

sorry I meant 6amp, I just decided to buy 100m roll of 2.5mm was no real reason behind it haha and I got a quote from Bells electrical which is the "Local" electrician company in my area and they were asking (with trench already dug) for £480.99 and could you please expand on your last sentance

 

[Diesel]

sory for late reply it didnt update for some reason =|

 

[The Ghost]

I think if you find it hard to raise money, going through building control can cost around £250. Whereas an electrician can save you that if he is registered with a CPS body. As well you are required to notify 48 hours prior to even starting work. So you will have to use an electrician who can self certify as you have already started. I am sure you can find someone who will tell you what exactly you need to do and oversee for less than the building control cost. I know I would do that, and you would be an instructed person which is perfectly ok. I imagine barring very strange wiring problems it would take no more than a couple of hours (for the electrician). You get the experience and the work done for around £100... ish ? with a certificate.

 

[Taylortwocities]

I think if you find it hard to raise money, going through building control can cost around £250. Whereas an electrician can save you that if he is registered with a CPS body. As well you are required to notify 48 hours prior to even starting work. So you will have to use an electrician who can self certify as you have already started. I am sure you can find someone who will tell you what exactly you need to do and oversee for less than the building control cost. I know I would do that, and you would be an instructed person which is perfectly ok. I imagine barring very strange wiring problems it would take no more than a couple of hours (for the electrician). You get the experience and the work done for around £100... ish ? with a certificate.

@Vortigern
Thank you.
I would like to take your splendid post and conserve it in a gold plated cask and present it (virtually) to other DIYers who are want to implement their own notifiable installations.

 

[Nickj]

There are many considerations you have to think about when taking a supply to a garage.

What type of supply does the house have? If it is TN-C-S you have additional considerations to make.

Additionally you need to think about time delayed RCDs, correct sizing of the cable running to the garage, the correct laying of the cable, protection of cable within the garage.

It's impossible to answer all of the questions relating to a garage install without a lot more information/seeing the job.

As has been said consult an electrician who can help you understand all of the considerations. Together you can work out a plan of action. You can then implement the plan as an instructed person and he can certify. It won't cost a lot.

 

[Diesel]

Appreciate all the support, have gone ahead and cracked on anyway, sheds powered up, secure and firing on all guns. Thanks!

 

[DPG]

You have made sure that a qualified electrician has tested and certified this install? And the customer has the relevant paperwork? Daz.