Welcome, Guest. Please Login or Register
Welcome To Ask The Trades!
Mar 29th, 2024, 1:06am
Quote: Depression is merely anger without enthusiasm.


Page Index Toggle Pages: 1
Send Topic Print
Sub-main wiring (Read 12447 times)
Dave
Junior Member
**
Offline

I love YaBB 1G - SP1!

Posts: 7


Total Thanks: 0
For This Post: 0



Sub-main wiring
Jun 22nd, 2004, 10:42pm
 
I am just completing the rewiring of an old house and have to arrange to get the meter moved from an internal position to an external box. The distance from the meter box to the fuse board will be approx 7m (cable run). I am told that this means I will have to install a sub-main, consisting of a pair of 100A tails from the fuse board to an isolating switch and from there to the meter. My question is about the siting of the isolating switch: I am not allowed to put this into the new meter box, so intend to put it into another housing inside the house. This will be approx 1.5M distant from the meter box. Is this OK, or are there regulations about how far away the isolating switch can be from the meter?
Back to top
 
Thank User For This Post  
IP Logged
 
plugwash
Administrator
*****
Offline

I love YaBB 1G - SP1!

Posts: 1383


Total Thanks: 0
For This Post: 0



Trade: Not Specified

Re: Sub-main wiring
Reply #1 - Jun 22nd, 2004, 11:43pm
 
that should be ok

a lot of sparks apparenly just put them in the meter box

might be an idea to ask your rec if they are ok with this

also iirc you should have your own overcurrent protection as well as isolation

and finally while you may be allowed to use tails i personally dislike the idea of runnign unprotected conductors of that capacity for any significant distance

contactum do a 2 way metalclad CU with a 100A isolator http://www.tlc-direct.co.uk/Products/CMM2N.html and a 100A 2 module wide mcb (http://www.tlc-direct.co.uk/Products/CMDK401.html)

you will want to remove the busbar and neutral bar link and wire the mcb direct to the rcd with single or tail but its a practical cheap and resetable option
Back to top
 
Thank User For This Post WWW plugwash plugwash 107767391 peter_m_green_zyworld_com plugwash  
IP Logged
 
Dave
Junior Member
**
Offline

I love YaBB 1G - SP1!

Posts: 7


Total Thanks: 0
For This Post: 0



Re: Sub-main wiring
Reply #2 - Jun 22nd, 2004, 11:50pm
 
Thanks for that. I agree that the idea of using tails over that distance isn't entirely satisfactory.

Can you clarify the rcd comment? I checked the Contactum Metalclad board and it appears to be supplied with a 100A isolator switch, but are you suggesting the addition of an rcd also?
Back to top
 
Thank User For This Post  
IP Logged
 
big_all
Global Moderator
Trade Member
Author
*****
Offline

heeelllooo
Posts: 5596


Total Thanks: 10
For This Post: 0


Gender: male

Trade: Joiner



Re: Sub-main wiring
Reply #3 - Jun 23rd, 2004, 12:03am
 
helllooo dave
welcome to the house off fun[madness] Grin Grin Grin
Back to top
 

big all ---------------  we are all still learning
Thank User For This Post View members image gallery  
IP Logged
 
plugwash
Administrator
*****
Offline

I love YaBB 1G - SP1!

Posts: 1383


Total Thanks: 0
For This Post: 0



Trade: Not Specified

Re: Sub-main wiring
Reply #4 - Jun 23rd, 2004, 12:11am
 
i said mcb not rcd

that thing despite being 2 modules wide is just a mcb
its just they need to make them that size at 100A Wink

ignore the long cable and clamp thing in the kit they are for putting it in an extention box on a contactum 3 phase board
Back to top
 
Thank User For This Post WWW plugwash plugwash 107767391 peter_m_green_zyworld_com plugwash  
IP Logged
 
supersparky
Administrator
Trade Member
Author
*****
Offline


Posts: 6097


Total Thanks: 3
For This Post: 0


Gender: male

Trade: Electrician



Re: Sub-main wiring
Reply #5 - Jun 23rd, 2004, 7:31am
 
http://www.tlc-direct.co.uk/Main_Index/Consumer_Units_Index/Hager_Metalclad_Rang...

simply cos hager are pathetic units

http://www.tlc-direct.co.uk/Products/HGNC163.html

no need for double pole.

the problem with that setup is you would be limetedto 63 amps- this wouldent trip the mcb at a slight overload for a long time though.

personly id just fit
http://www.tlc-direct.co.uk/Products/WY110M.html
with
http://www.tlc-direct.co.uk/Products/MM100SO.html
or http://www.tlc-direct.co.uk/Products/MM80SO.html
because ive always done that, and its the normal way to do it, ive stuck them in the rec boxs out side before now on occasion....they are quite bulky though-
as for the run, well thats what http://www.tlc-direct.co.uk/Products/SW16slash3.html is for
although 25mm is what id probrably use - depends on house size and main fuse raiting

ss
Back to top
 
Thank User For This Post WWW  
IP Logged
 
Dave
Junior Member
**
Offline

I love YaBB 1G - SP1!

Posts: 7


Total Thanks: 0
For This Post: 0



Re: Sub-main wiring
Reply #6 - Jun 23rd, 2004, 9:08am
 
Thanks for all the help guys. I'm a lot wiser now. However, it all turned out to be a bit of a red herring. I phoned ABB, the company that are moving the meter installation, and asked them if it would be OK to put my isolator switch/fuse inside the new outside meter box. They then told me that this is something they install themselves as standard! All I need to do is run the 100A sub-main cable to the box.
Back to top
 
Thank User For This Post  
IP Logged
 
Lectrician
Administrator
Trade Member
Author
*****
Offline

Ask The Trades
Posts: 8814


Total Thanks: 108
For This Post: 0


Braunton, North Devon, United Kingdom
Braunton, North Devon
United Kingdom

Gender: male

Trade: Electrician



Re: Sub-main wiring
Reply #7 - Jun 23rd, 2004, 4:46pm
 
Ask your REC what the maximum tails distance is, our REC doesnt give a limit anymore for 25mm tails.  3m for 16mm tails.

Other than that, do what was said.  Some RECS will install a douple pole 100map switch in the box, it is their property.

You can pay for another meterbox to go adjacent to theirs (by it from them), for your kit.
Back to top
 

Need to post a picture? Click HERE for info!
Thank User For This Post WWW View members image gallery  
IP Logged
 
LSpark
Global Moderator
Trade Member
Author
*****
Offline


Posts: 8069


Total Thanks: 3
For This Post: 0


London, UK, United Kingdom
London, UK
United Kingdom

Gender: male

Trade: Electrician



Re: Sub-main wiring
Reply #8 - Jun 23rd, 2004, 10:47pm
 
where you located Dave?
Back to top
« Last Edit: Jun 23rd, 2004, 10:48pm by LSpark »  
Thank User For This Post View members image gallery  
IP Logged
 
Lectrician
Administrator
Trade Member
Author
*****
Offline

Ask The Trades
Posts: 8814


Total Thanks: 108
For This Post: 0


Braunton, North Devon, United Kingdom
Braunton, North Devon
United Kingdom

Gender: male

Trade: Electrician



Re: Sub-main wiring
Reply #9 - Jun 24th, 2004, 8:01am
 
missed your last post somehow dave!!  I think i was offline looking at a 'saved' page somehow !?!?!?!
Back to top
 

Need to post a picture? Click HERE for info!
Thank User For This Post WWW View members image gallery  
IP Logged
 
Dave
Junior Member
**
Offline

I love YaBB 1G - SP1!

Posts: 7


Total Thanks: 0
For This Post: 0



Re: Sub-main wiring
Reply #10 - Jun 24th, 2004, 8:44am
 
The property is located in Rutland. The service provider is Powergen.

My local wholesaler tells me that because Rutland is in the Eastern Electricity area, their sub-contractors automatically install isolating switch/fuses when moving a meter. Other areas do not, apparently.

It seems there is a lack of standardisation on this issue.
Back to top
 
Thank User For This Post  
IP Logged
 
LSpark
Global Moderator
Trade Member
Author
*****
Offline


Posts: 8069


Total Thanks: 3
For This Post: 0


London, UK, United Kingdom
London, UK
United Kingdom

Gender: male

Trade: Electrician



Re: Sub-main wiring
Reply #11 - Jun 24th, 2004, 3:52pm
 
ok dave, i thought it must be subcontracted out to ABB, and that area sounds just about right  Wink
Back to top
 
Thank User For This Post View members image gallery  
IP Logged
 
Page Index Toggle Pages: 1
Send Topic Print