What Sized Armoured Cable?

[neil3950]

Hello.

I want to run an extension cable from a pre-existing mains socket in my garage, out through a hole in the wall and buried underground for approx 12 mtrs length to a 4 way strip adapter that wiill be housed inside a specific outdoors sealed box unit. I will be using the strip adapter to plug in transformer plugs that power low voltage LED lighting in my garden.

I realise I must use SWA cable but what size? I've seen that you can get 3 core 1.5mm , 2.5mm and 4mm?

Additionally, at the end of the cable that goes into my garage would I terminate the SWA cable directly on an RCD that plugs into the wall socket or use an alternative method?

Thanks.

 

[Steve]

You shouldn't need the RCD plug top if the garage is already RCD protected. There is no benefit of having 2 RCDs of the same rating protecting the same load.

And the SWA will need terminating both ends in a suitable adaptable box using the correct glands for the job. The purpose of the armour is to provide an earth path if the cable is sliced, and therefore cut the power by providing a sudden surge of electricity which trips the breaker or rcd or fuse, so the armour MUST be earthed.

And this ought to be part p notifiable being as you are burying the cable and the glands need to be fixed to something, but i'm sure someone will argue its not.

 

[neil3950]

Thanks Crafty. can you please confirm what size armoured cable I should use? Thanks

 

[ban-all-sheds]

I realise I must use SWA cable but what size?

http://www.tlc-direct.co.uk/Technical/Charts/VoltageDrop.html

Select 2-core PVC SWA, or it doesn't work properly.

I've seen that you can get 3 core 1.5mm , 2.5mm and 4mm?

And 6mm², 10mm², 16mm², 25mm²......

Additionally, at the end of the cable that goes into my garage would I terminate the SWA cable directly on an RCD that plugs into the wall socket or use an alternative method?

You've never used SWA, or looked into it at all, have you?

It needs to be properly terminated in a gland like this:

Remove locknut 3.
Strip cable outer sheath and pass shroud then outer nut 1 over cable.

Pass cable end through gland inner 2 and spread out armour wire over cone.

Screw outer nut 1 onto inner 2 and tighten.

Insert gland bush 4 into cable entry of apparatus and tighten locknut. Push shroud back over gland.

See //www.diynot.com/forums/viewtopic.php?t=27081 for one man's trials, with photos.

 

[neil3950]

Thanks ban, some excellent info there.

You are correct in suggesting that I have never used SWA cable and fittings before.

The end of the cable that will terminate in the garage I was intending on connecting to a normal 3 pin plug, to plug into a socket as normal as opposed to wiring into a consumer unit of sort, which I presume will take away the part p compliance area? I guess you can give me the definite answer on this.

From your experience what would be the best way to achieve this?

Many Thanks

 

[Softus]

The end of the cable that will terminate in the garage I was intending on connecting to a normal 3 pin plug...

Just in case you were still thinking that this is possible, it isn't. You have zero chance of wiring SWA cable into a UK plug top.

In fact, it's so impossible to do it that your chances are less then zero!

 

[Adam_151]

I might take you up on that challenege Softus, sure it won't be pretty, but...

 

[BJS_Spark]

I didn't think part P applied up in Scotland?!?

 

[neil3950]

Can anyone confirm if part B does apply in Scotland?

 

[Steve]

Can anyone confirm if part B does apply in Scotland?

if you mean part P, no it doesn't. bugger.

 

[neil3950]

thanks crafty - did mean part p sorry. well thats good to know. are you aware of any other regs particular to scotland that i must adhere to?

thanks.

 

[supersparky]

hold on a second, read back, the poster just said hes going to terminate the swa into a 3 pin polug and plug it into a normal socket at the garage end to save a consumer unit!!!!

has no one noticed that the pins on the plug will be live at all times and got help anyone who unplugs it......

 

[ban-all-sheds]

hold on a second, read back, the poster just said hes going to terminate the swa into a 3 pin polug and plug it into a normal socket at the garage end to save a consumer unit!!!!

Hold on a third, and read back:

I want to run an extension cable from a pre-existing mains socket in my garage,

Additionally, at the end of the cable that goes into my garage would I terminate the SWA cable directly on an RCD that plugs into the wall socket or use an alternative method?

The end of the cable that will terminate in the garage I was intending on connecting to a normal 3 pin plug, to plug into a socket as normal as opposed to wiring into a consumer unit of sort

has no one noticed that the pins on the plug will be live at all times and got help anyone who unplugs it......

No.

Third emoticon along, third row down is the one you're looking for...

 

[Softus]

I might take you up on that challenege Softus,

Go for it Adam, but you have to get the lid on too

 

[ban-all-sheds]

Is it OK to use 1.5mm² 2-core?