Running power to a shed

[basset]

I need to run 25m of 2.5mm armored cabling to a shed. The consumer box has no RCD protection and no spare slots for a RCBO, so I'm thinking of putting an external RCD box next to the main consumer box, any thoughts on this would be most appreciated. i.e how do you split power off to a seperate box

When in the shed I need a box that splits the power for lights 6a and socket 20a. I don't think this needs to be RCD protected?

Any advice would be most appreciated

Best regards
James

 

[Silly Sausage]

Have a read of this first...
http://www.electriciansforums.net/e...ide-exported-pme-outbuildings.html#post217459

 

[telectrix]

next to the CU fit a " garage board" comprising a 40A,30mA RCD and a MCB. i would use 6mm 3 core SWA on a 32A MCB. at the garage, fit a 2nd unit with a 20A and a 6A MCB. take the earthing from the house.

 

[white armour]

Hi James, personally I would put a 2way RCD board at the shed end of the circuit, no need to additionally protect SWA.

You can use Henley blocks to split your supply tails and then into a double pole switch for your isolation of the shed supply circuit.

Remember to upgrade your supply tails/main earthing & bonding if needed.

Regards wa

 

[Lighthouse Phil]

Upgrade your SWA to at least a 4mm, if not a 6mm.
At your CU, install a 2way modular box to accept your RCBO. Take your supply from the Phase and Neutral bus bars, join your earth from the SWA banjo and the earth from the SWA to the earth bar. Install your new CU in shed, go for a pint, job well done, pat on the back......failing that, get your local spark to do it, buy him a pint too....

 

[white armour]

Or you could do it tels way, as he types quicker than me.

Regards wa

 

[telectrix]

rcd can go either end, but overload protection in the house is essential to protect the SWA. 2.5mm would just be adequate for a 16A and a 6A circuit in the shed, but no allowance for future increase in load. i would deffo go for 6mm.

 

[tony mc]

Whats your earthing arrangement at the house ???

 

[basset]

Wow so much advice, I really do appreciate it guys.

So how about I go for the 6mm cable and a 2 way modular box with an RCBO to protect the SWA and electrics in the shed?

At the shed end fit a 2nd unit with a 20A and a 6A MCB. take the earthing from the house.

And by the way its a TN-S system

Regards
James

 

[basset]

Am I right in saying that I can attach the SWA to the top of a wall. Only thing is, its only 1 1/2 foot tall?

 

[telectrix]

sounds good. you can run the SWA anywhere it will not be prone to damage. on the vertical face of a wall is better than on the top.

 

[sythai]

you can run the SWA anywhere it will not be prone to damage.

Got one of these in couple of weeks.

Thoughts on running along top of wooden fence - solid as newly installed, posts solid as set in concrete.. proper job - thats where I'm putting anyway, otherwise it's concrete paths up and all sorts:waving:

Definitely go for the 6mm - bit of future proofing, you never know they may want to stick a 2kW heater out there when it gets a bit frosty

 

[basset]

Right you are, SWA across the vertical face of the wall.

Just another quick question: how do I install the 2 way modular box to the current consumer unit?

Sorry about all the questions but i'm very new to this. I've got my NICEIC assessment on the 19th Aug, wish me luck

 

[Silly Sausage]

Right you are, SWA across the vertical face of the wall.

Just another quick question: how do I install the 2 way modular box to the current consumer unit?

Sorry about all the questions but i'm very new to this. I've got my NICEIC assessment on the 19th Aug, wish me luck

I think the usual way is to split the tails from the meter via a Henley block, one pair to your original CU and 2nd pair to your new 1 way box containing suitably sized breaker, and the SWA from there via a suitable connection.

 

[basset]

WOW split the tails. I assume I will need to isolate the power by pulling out the main fuse. So I need to get permission from the supplier yeah?

 

[Silly Sausage]

Hahaha...pulling the fuse, numerous threads on that subject.
Personally if it appears to be in good condition, cut the seal and take it out. Remember, don't work LIVE unless there is absolutely no way not to.

There's a certain other forum where they abhor fuse pulling and they've got lots of horror stories to tell.

I'll leave it there. You'll get more advice from others.

 

[Geordie Spark]

Hahaha...pulling the fuse, numerous threads on that subject.
Personally if it appears to be in good condition, cut the seal and take it out. Remember, don't work LIVE unless there is absolutely no way not to.

There's a certain other forum where they abhor fuse pulling and they've got lots of horror stories to tell.

I'll leave it there. You'll get more advice from others.

It won't have a seal on it ....... will it ??!!

 

[Silly Sausage]

It won't have a seal on it ....... will it ??!!

Hey, we're all professionals here!

Reminds me of something nearly 30 years ago, renting council flat in Hulme, Manchester. Me mate calls the gas board out cos he smell gas. Engineer turns up and deals with it and says 'This was your problem, I found it under the meter' rubber washer from one of the pipe joints to the meter. I'll let you draw your own conclusions on that...

 

[Geordie Spark]

Hey, we're all professionals here!

Reminds me of something nearly 30 years ago, renting council flat in Hulme, Manchester. Me mate calls the gas board out cos he smell gas. Engineer turns up and deals with it and says 'This was your problem, I found it under the meter' rubber washer from one of the pipe joints to the meter. I'll let you draw your own conclusions on that...

It never ceases to amaze me just how many folk neglect to splash a bit of Leak Detection Fluid about after they've turned their meters around.... :uhoh2:

 

[Silly Sausage]

I know, sheer wrecklessnessss.

Another occasion, council flat in London, dubious diy meter work, we'd been there about 4 years and it was reading less than when we moved in, one of the hottest summers on record and we've got the heating on full and all the gas rings burning trying to get it to a sensible reading. Happy days, energy was cheap then! (this is all a long time ago, wouldn't dream of doing it now)

 

[Geordie Spark]

I know, sheer wrecklessnessss.

Another occasion, council flat in London, dubious diy meter work, we'd been there about 4 years and it was reading less than when we moved in, one of the hottest summers on record and we've got the heating on full and all the gas rings burning trying to get it to a sensible reading. Happy days, energy was cheap then! (this is all a long time ago, wouldn't dream of doing it now)

Neither would I. :aureola:

 

[Silly Sausage]

Neither would I. :aureola:

Aye, these new fangled card meters...

 

[malcolmsanford]

Wow so much advice, I really do appreciate it guys.

So how about I go for the 6mm cable and a 2 way modular box with an RCBO to protect the SWA and electrics in the shed?

At the shed end fit a 2nd unit with a 20A and a 6A MCB. take the earthing from the house.

And by the way its a TN-S system

Regards
James

James as it is a TN-S system I would advise putting a small garage board with the RCD protection in the shed itself and not the house.

Nothing worse than tripping the RCD while in the shed and having to walk the 25 metres back to the house to reset it.