Garage power supply

SWA cable would be cheaper, easier to install, and better.

I do have it, but there is a sharp 90 degree bend where it leaves the house wall. That was bothering me mainly for visual reasons. It looks tatty.

Cheers for the reply :)

On Fri, 18 May 2007 00:55:34 GMT, EricP mused:

Have you already drilled this hole? If not, drill it at an an angle, or re-drill it to suit. Other option is terminate the SWA into a box over the hole.

A box! Very simple and obvious.

I will buy a brain tomorrow.

Cheers, :))

|!In article , |! EricP wrote: |!> Is there a FAQ? |! |!> If not, the proposed 5m run along a fence is 2.5 T&E in black 20mm |!> conduit with usual inspection joints along it. Fused at 16 amp for a |!> minor supply. |! |!> At the garage a CU will distribute to one socket and lighting. |! |!> Any pointers please? |! |!SWA cable would be cheaper, easier to install, and better.

Thanks for that, never heard of it till now! I am also about to move my garage, and move the electrics at the same time. The choice would appear to be hang SWA from a wire, or bury it, (under the concrete base?). What are the present rules for installing SWA cable. both above and below ground? I have several spare 15 amp fuses on my Consumer Unit and at present have a RCD/distributor unit

On Thu, 17 May 2007 19:39:10 GMT someone who may be EricP wrote this:-

Fences are liable to being blown over. As a result electrical systems should not be attached to them.

Walls are a different matter.

I've got the same job running an electrical supply to my garage i was thinking it would be best underground - more permanent but would need to be protected from above by little concrete blocks I think you can buy for the purpose. What is SWA ? Also is a consumer box needed in the garage if the supply comes from your house consumer box.

What is the max continuous current rating of 2.5mm dia cables (in excess of 30A I guess?)

More like 20A. But that depends on how it is run, grouping, etc.

SWA = Steel Wired Armoured. For a picture, see

I'm sure that somewhere on the TLC site there's some information about current ratings for different cable types and sizes - which depend on where the cables are located - but I can't find it. Maybe someone can provide a reference?

Going through/under concrete, I would duct it, so that it can be pulled out and replaced if necessary. Probably okay to use some plastic drainpipe for the duct, although it's probably the wrong colour (every underground service has a designated colour for ease of recognition).

There is no minimum depth but it has to be suitable for the location - greater than two spits deep under the veggie plot where double-digging may take place, to quite shallow under paths.

Always a very good plan to put some "buried cable below" tape between the cable and the surface.

Owain

This should provide the information needed.

On Fri, 18 May 2007 10:08:20 +0100, Owain mused:

Black for mains, so use black waste pipe. ;)

On 18 May 2007 01:25:43 -0700, 405 TD Estate mused:

I think you're thinking of the concrete ducts used on railways etc... A tad excessive I believe.

Not neccesarily, usually one is fitted but if you have a 16A supply running from the house we have run this through an isolator and then used a fused spur for the lighting.

Nope.

I think I would need at least 30A to run my plug in welder, 3kw electric heater and a couple of floodlights and 3 flourescent lights. So this looks like 6mm^2 cable required - which would give 30A (just).

So a consumer unit would be needed?

Additionally if for example I want to run my sockets from one outlet of the consumer unit but it is more convenient to run them all from one single point (instead of a ring main) what type of box can you get with rails for +ve -ve and earth to easily connect them up.

The current carrying capacity of SWA is also influenced by what it is sheathed in. The PVC type can run upto 70 degrees like most house cable, but XLPE thermosetting insulation will go to 90 and hence carry higher currents.

If you are looking at a number of circuits then that is the simple way.

A simple shed supply with a couple of sockets and a light could get away with a switch and a direct connection the the sockets with the lights of a FCU.

It also depends on what you are doing in there. Using a space as a workshop for example will mean you need to pay for more attention to issues like discrimination - i.e. keeping the lights on when you trip a power circuit.

Not sure I quite follow that description... but it sounds like you are describing a CU.

Having put in your new consumer unit in the garage - one final tip:

Next time the electricity supplier sends a kid round to change the meter, make sure you point out the garage feed to him. I went to add a new switch in the garage recently and found the whole thing live: the meter had been changed and the connector block that had been live before was now the neutral, and vice versa. The board's electrician, swapped over the connector polarity even though the garage feed wires were right in front of his eyes and clearly not the right colour.

Had to break the seal on the main fuse to swap it over safely...