ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Top Posters(30 Days)
twh 10
Admin 4
Recent Posts
Dryer, Range grounding from "Main" panel
by sparkync. 05/23/17 03:32 PM
Any UL 508 experts out there?
by sparkyinak. 05/21/17 08:57 PM
Heat pump conundrum
by sparkyinak. 05/21/17 08:49 PM
Interesting week
by HotLine1. 05/20/17 11:57 AM
Electrical Pricing Guide
by ElectricianBud. 05/18/17 12:17 PM
New in the Gallery:
SE cable question
Popular Topics(Views)
236,663 Are you busy
171,639 Re: Forum
164,625 Need opinion
Who's Online Now
1 registered members (brsele), 58 guests, and 10 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#146000 - 09/08/06 02:50 PM Summer house  
Kenbo  Offline
Member
Joined: Apr 2006
Posts: 233
Scotland
OK
Just a quick question becouse I am away from my office and can not get a hold of my 16th Regs till Monday.

Friend has just phoned (I have not seen this set up yet) he is building a summer house in his garden timber I suspect. He plans to install power via 35 Meter 10mm sq SWA.

I recon the cable would be ok
but I would like to see it supplied from a 40amp RCD to a small consumer unit in the summer house with a earth spike. ( I do not know eathing set up in his house at the moment)

Any thoughts?


der Gro├čvater

Test Equipment:
Large Selection of Test Equipment For Electrical, HVAC, Test & Measurement
Large Selection of Test Equipment For Electrical, HVAC, Test & Measurement

#146001 - 09/10/06 06:37 AM Re: Summer house  
britspark  Offline
Member
Joined: May 2005
Posts: 54
southampton united kingdom
Kenbo,
what is he thinking of running off of that size SWA ?

run a three core 10mm and also use the armour for an earth (safer this way)

at origin, ie, meter DB position put it on a spare MCB in the board, (if he has one) and run it via an RCD,

this is due to it being `extraneous of the dwelling)

sticka two way or four way DB at the other end (matal board) and wire it from there.

and if it is a UK install ensure that the EC is PART P compliant company.

britspark


#146002 - 09/10/06 07:59 AM Re: Summer house  
Kenbo  Offline
Member
Joined: Apr 2006
Posts: 233
Scotland
Britspark

Thanks for your reply. I am happy with what you say about the DBs at each end.

I have not worked it out yet but I thought the 10mm would be sufficent regards the voltage drop and relatively small load.

What did concern me more was the fact that it is extraneous of the dwelling and such a distance from it.
So you recon earthing through the cable and the armour would be sufficent, and a spike would not be required

Kenny


der Gro├čvater

#146003 - 09/10/06 08:27 AM Re: Summer house  
uksparx  Offline
Member
Joined: Apr 2005
Posts: 44
Egremont,Cumbria,UK
My interpretation of the current regs. would also be that the 10mm is fine. If you are going to use an earth "spike" ( which may of course need more than one, depnding on soil resistance) then you would be advised to make it a TT system (with RCD) totally independent of the house earth. Remember also that if you choose this option you must dig down at least 600mm BEFORE you knock in the earth rods, to ensure a good connection. Otherwise stick to using one core and sheath of the SWA, remembering that if you have any extraneous metalwork in the summer house, e.g. pipes, these must be bonded as normal.


#146004 - 09/10/06 08:28 AM Re: Summer house  
pauluk  Offline
Member
Joined: Aug 2001
Posts: 7,520
Norfolk, England
What sort of load is going to be in the summerhouse? While I'm all for over-engineering to "be on the safe side" and to allow for future growth, I'm wondering what's going to be in there to warrant a 40A subfeeder. A 30A subfeed with 6mm SWA would still be within voltage-drop tolerances, even at full load.

If the hosue is PME, then a TT system with separate earth rod at the summerhouse might be the way to go (yes, I'm trying to put aside my personal dislike of TT arrangements [Linked Image] ).



Member Spotlight
SafetyWired
SafetyWired
Pa, USA
Posts: 44
Joined: July 2013
Show All Member Profiles 
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.011s Queries: 14 (0.002s) Memory: 0.7684 MB (Peak: 0.9052 MB) Zlib enabled. Server Time: 2017-05-23 22:39:45 UTC