Power Supply to Garage

by **AjayK46** » Sat Jun 20, 2009 4:10 pm

I have an existing power supply to my garage which just plugs into a socket on the ring main indoors (RCD protected) and only turned on when needed. The cable is arctic type but has become damaged where it enters the house. I need to replace the entire run but would rather not use the bright yellow or blue arctic cable. Could I use ordinary pvc 3 core flex or is there something else more appropriate that is either black, white or grey?

by **kbrownie** » Sun Jun 21, 2009 8:09 am

AjayK46
is your garage attached to your dwellling or is it a seperate building?
KB

by **AjayK46** » Tue Jun 23, 2009 3:45 pm

It's a separate building and there is an underground conduit to take cable across to the garage.

by **moggy1968** » Tue Jun 23, 2009 7:45 pm

you could be opening a can of worms there!!
is the conduit metal? if not then is it really suitable, i.e. does it offer adequate mechanical protection to the cable? probably not if the cable has become damaged, and artic cable is pretty tough. the only cable suitable for this purpose really is steel wire armoured. Flex is totally unsuitable.
strictly speaking your gareage should also have it's own seperate earthing system, although thats a bit open to interpretation, and it's own sub distribution board.
Any modification to this circuit will also require notification to building control before work commences, or needs to be done by a Part P registered competent person who can register the works as a detached garage comes under the auspices of part P.
The modified circuit will also need RCD protection if you don't already have it (it should be on it's own dedicasted circuit, not on the ring main).

by **AjayK46** » Wed Jun 24, 2009 4:29 pm

The artic cable is only being used as an extension lead to the garage and not as a permanent live connection. When I need power in the garage I plug the extension lead into a 13amp socket on the ring main next to where it comes through the wall from outside. The ring main is fully RCD protected.

The only reason the artic got damaged is because it got accidentally cut by a wall paper scraper when the room was being decorated and I have only just noticed it.

I really just want to replace the extension lead with an equivalent that is ideally not bright yellow or blue. (or can it not be as simple as that ?)

by **kbrownie** » Wed Jun 24, 2009 11:21 pm

Ajayk46,
I recommend SWA cable, find out what you intend to power up ie sockets/lighting and then we can do some calcs on cable size needed, as the garage is seperate it will likely be a part p carry on, so look on project pages: https://www.diydoctor.org.uk/projects/partp.htm and search for part p of building regulation. So you know what your getting yourself involved with.
KB

by **AjayK46** » Fri Jun 26, 2009 5:54 pm

It is used just for a 100w light bulb and a 1500w electric lawn mower at max.

Is it difficult to put a 13amp plug onto SWA cable? How flexible is it? (or not as the case may be) !

by **kbrownie** » Sat Jun 27, 2009 12:28 pm

Ajay, this should be hard wired direct to your CU not connected via plug.
How far is the garage from the dwelling?
Really your looking at 4mm SWA on a 32A breaker with RCD protection.
Fed from House CU to a garage CU then split in to 6A lighting and 20A power circuit.
KB

by **rosebery** » Sat Jun 27, 2009 12:52 pm

"Is it difficult to put a 13amp plug onto SWA cable?"

Not at all. Its quite, quite impossible!

Cheers

by **AjayK46** » Sun Jun 28, 2009 11:07 am

Ok - I can't afford the cost of having a consumer unit installed in the garage with dedicated supply from indoor consumer unit at the moment.

All I was wanting to do is replace like for like what has always been there which is a 20mtr run of artic cable with a 13amp plug into an indoor socket on the ring main. This would only be plugged in when power was needed in the garage so assumed that it would be treated as an extension lead. I was also hoping to replace it with something that was not bright blue or yellow.

Does arctic cable (or equivalent) come in anything other than yellow or blue to be used purely as an extension lead when required and not permanetly connected?

Any suggestions much appreciated.

by **kbrownie** » Sun Jun 28, 2009 4:36 pm

AjayK46,
Don't take this the wrong way but lets be safe about this one!
It's simply not the done thing, just because it was originally there, don't make it right! It's foolish to think that, you wouldn't use a rubber hose pipe to connect up a gas heater in the garage via your gas hob or fire, and if you bought a house with something like that already in place would you consider it safe and continue using it?
Fixed accessories should not be powered up using extension leads! BS7671:2008 says not and that's the electrician bible with directives and guidelines that concern Part P and Electricty at works act and these are legal documents.
You've come to a site that was already offered, through a number of members the correct and safe way to do this.
Safety is paramount and I would not recommend anything that I considered unsafe to you, your family, friends and property.
Can you afford to take that risk?
KB

by **rosebery** » Sun Jun 28, 2009 6:18 pm

"Ok - I can't afford the cost of having a consumer unit installed in the garage with dedicated supply from indoor consumer unit at the moment."

KBs advice is what is safe, what is required for the job to be done properly and what is legal. Noone with any sense is going to give you the OK to do anything else. Irrespective of anything else your exisiting installation isn't safe but if you don't like the advice given you are free to disregard it.

I think thats probably this thread finished then.

Cheers

by **moggy1968** » Sun Jun 28, 2009 8:56 pm

to my knowledge it is only in blue when rated high enough for what you want. 20m is a long run, that suggests your garage is someway from the house so the existing setup really isn't a goer. It's just not safe and thats why everyone is telling you to use SWA. yes you have gotr away with it so far, you can get away playing russina rullete for a while but I wouldn't reccomend you make a habit of it!
100amp tungsten bulbs are no longer available.
I'd suggest buying an RCD protected extension lead as
the cheapest way of cutting your lawn in the short term!
seriously, this needs doing properly.
there is a way of terminating SWA into a plug, but I'm not going to share that with you I'm afraid because it shouldn't be done.

by **AjayK46** » Thu Jul 02, 2009 9:43 am

Thank you for all your help. I will use an RCD protected extension lead for the time being for cutting the lawn. When funds permit I will have everything done properly by an electrician.

by **kbrownie** » Thu Jul 02, 2009 5:57 pm

[quote="AjayK46"]Thank you for all your help. I will use an RCD protected extension lead for the time being for cutting the lawn. When funds permit I will have everything done properly by an electrician.[/quote]
Good to hear that Ajay, an alternative is to replace a socket outlet with an RCD protected socket-outlet at the point you intend to plug your extension lead in. but you can't carry that around with as you can with a reel that has RCD protection.
KB