Welcome, Guest. Please Login or Register
Welcome To Ask The Trades!
Mar 28th, 2024, 8:10pm
Quote: Creativity is great, but plagiarism is faster.


Pages: 1 2 
Send Topic Print
Strange Ring Extension (Read 15898 times)
PoorOldWil
Junior Member
**
Offline

If it ain't broke, it
soon will be!
Posts: 6


Total Thanks: 0
For This Post: 0


Gender: male

Strange Ring Extension
May 3rd, 2004, 10:32am
 
Hi folks,

I recently lifted some floorboards in a bedroom, to reveal the tangle of cables and 'floating' JBs that
make up my fixed wiring. My house has a kitchen extension, and the power ring circuit for this seems to
come from one of these JBs, as two 2.5mm2 cables. This JB is connected to a second JB, on one of the main rings,
by a length of heavier cable ( 4mm2 or 6mm2, not sure).  So it looks as though the entire ring circuit for the kitchen is
wired as a spur from the main ring. I have never seen this method of extending a ring described in books - does it
comply with the Regs?? The kitchen ring powers 5 x 13A sockets, a FCU to a dishwasher, a FCU to a 1kW water heater and
a FCU to a 150W towel rail heater: so I guess the 4/6mm2 cable is not overloaded (it's been like that for years!).
BTW I checked that the circuit is a ring, not a 'tree' spur.

Never look under the floorboards - there are things there that mere mortals should not see!!

Wil
Back to top
 

Wil
Thank User For This Post  
IP Logged
 
HM
Super Member
*****
Offline

Chief Turd Polisher
Posts: 5072


Total Thanks: 0
For This Post: 0


Gender: male

Re: Strange Ring Extension
Reply #1 - May 3rd, 2004, 10:42am
 
This does not sound as though it complies with the regs at all.

Are the connections between these bits of wire made with terminal blocks? If so, instantly outside the regs because termination blocks should only be used in accessible locations (and I don't view under the upstairs floorboards as being accessible).

Also, a spur should be just that - one radial t&e to a fused spur. Not an entire circuit like what it seems you have in there.

You home insurance company might not be pleased to have a claim against them in the event of a fire, so now that you are aware there could be a problem you need to get this fixed.

Andrew
Back to top
 

If you aren't always sure of the right answer don't take up a career in the bomb squad
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: Strange Ring Extension
Reply #2 - May 3rd, 2004, 11:30am
 
regs require junction boxes to be accessible though in reality they very rarely are

if possible remove the jucntion boxes completely and replace all cables comeing out from the pair of junction boxes with 2 new cables to give one continous ring with no junction boxes

failing that remove one cable from the main ring to the pair of junctino boxes and one cable from the mini ring to the pair of junction boxes and run a new cable between theese sockets to give a proper ring but with the junction boxes left in

failing that remove one cable from each or the pair of junction boxxes and join them with mroe junction boxes and cable but i really wouldn't wan't to introduce so many junction boxes
Back to top
 
Thank User For This Post WWW plugwash plugwash 107767391 peter_m_green_zyworld_com plugwash  
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: Strange Ring Extension
Reply #3 - May 4th, 2004, 1:31am
 
and failing that!, get a spark in to do it mate, you could risk electricution quite easily handling this yourself, especialy with JB everywhere! - up to you!  Undecided
Back to top
 
Thank User For This Post View members image gallery  
IP Logged
 
PoorOldWil
Junior Member
**
Offline

If it ain't broke, it
soon will be!
Posts: 6


Total Thanks: 0
For This Post: 0


Gender: male

Re: Strange Ring Extension
Reply #4 - May 4th, 2004, 8:45am
 
Thanks to all for your advice - looks like I have some re-cabling to do! By repositioning a couple of sockets, I can complete the ring using two sets of connections, which I can put above the floor so that they are accessible.

I lifted a few more boards and found other horrors - the 6mm2 feed to the kitchen hob/oven comes up through the ceiling from the CU below, straight into a JB then on to a second JB where it connects to new cable to the kitchen extension. The force needed to cram two 6mm2 cables into the first JB has broken the box - large bits of plastic left there - and the broken JB 'floating' by the cables Shocked.   No option here but to re-cable back to the CU!

The extension was done by a reputable (?) local builder, but I think the electrics must have been done by the brickie's labourer in his tea-break!
Back to top
 

Wil
Thank User For This Post  
IP Logged
 
HM
Super Member
*****
Offline

Chief Turd Polisher
Posts: 5072


Total Thanks: 0
For This Post: 0


Gender: male

Re: Strange Ring Extension
Reply #5 - May 4th, 2004, 12:51pm
 
[quote author=PoorOldWil  link=1083576748/0#4 date=1083656715]Thanks to all for your advice - looks like I have some re-cabling to do! By repositioning a couple of sockets, I can complete the ring using two sets of connections, which I can put above the floor so that they are accessible [/quote]

If ya crimp the cable joins then ya can bury them. It's only choccy blocks that have to be accessible.

Andrew
Back to top
 

If you aren't always sure of the right answer don't take up a career in the bomb squad
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: Strange Ring Extension
Reply #6 - May 4th, 2004, 2:04pm
 
well if it's (the crimps) not contained in anything, at minimum tape them all up, i would put in a chocbox regardless tho, JB's arent exactly accesible under the floor are they? so why should chocboxes be? not that im saying its best, but having things accesible just doesnt happen!  Roll Eyes
Back to top
 
Thank User For This Post View members image gallery  
IP Logged
 
HM
Super Member
*****
Offline

Chief Turd Polisher
Posts: 5072


Total Thanks: 0
For This Post: 0


Gender: male

Re: Strange Ring Extension
Reply #7 - May 4th, 2004, 4:23pm
 
[quote author=L.Spark  link=1083576748/0#6 date=1083675873]well if it's (the crimps) not contained in anything, at minimum tape them all up, i would put in a chocbox regardless tho, JB's arent exactly accesible under the floor are they? so why should chocboxes be? not that im saying its best, but having things accesible just doesnt happen!  Roll Eyes [/quote]

I'll be happy to bow to your greater authority on the subject if need be, but my understanding was that choccy blocks were not allowed if they aren't accessible. Whereas crimped connections can be buried.

I agree 100% that the crimps should be taped, or perhaps even better put in JBs. Tape can be a pain in the arse to get undone again in future should that joint ever need to be exposed.

Stanley knives at the ready chaps! Wink

Andrew
Back to top
 

If you aren't always sure of the right answer don't take up a career in the bomb squad
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: Strange Ring Extension
Reply #8 - May 4th, 2004, 6:23pm
 
most types of connection are supposed to be accessible however junction boxes rarely are

the things that don't need to be accessible include (there may be others)

crimped joints
soldered joins
resin encapsuated joints
Back to top
 
Thank User For This Post WWW plugwash plugwash 107767391 peter_m_green_zyworld_com plugwash  
IP Logged
 
mart_the_spark
Re: Strange Ring Extension
Reply #9 - May 4th, 2004, 6:24pm
 
bit worrying, 'perhaps in jb'.....

Surly if you are gonna use through crimps you gona but them in a gewiss box or similar arnt you??

And tape??  Heat shrink sleeve would be your best bed for the non insulated types.
Back to top
 
Thank User For This Post  
IP Logged
 
PoorOldWil
Junior Member
**
Offline

If it ain't broke, it
soon will be!
Posts: 6


Total Thanks: 0
For This Post: 0


Gender: male

Re: Strange Ring Extension
Reply #10 - May 4th, 2004, 6:56pm
 
Some useful ideas on connections..not too sure about crimps, as I'll be using single-conductor t+e cable: I think
crimps are best with stranded-core cables.  Having sorted out the various JBs that litter the underfloor space,
I have to re-position and reconnect one 3core+cpc lighting circuit; two 2.5mm2 t+e for the kitchen ring; one 6mm2 t+e
for the kitchen oven/hob and one 6mm2 t+e feed to the garage. As the room above the floor is being converted to an
en-suite bathroom (which is why I lifted the boards in the first place!), I'm a bit limited in where I can put the
connections: they will have to go in a closed compartment which houses the shower pump. No doubt the pump will
blow its pushfit connectors at the first opportunity, so I'll make all the connections in a IP66 box,
using 35A DIN terminals on a rail.

Wil
Back to top
 

Wil
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: Strange Ring Extension
Reply #11 - May 4th, 2004, 7:15pm
 
any box with more than one cuircuit entering should be clearly labled as such
Back to top
 
Thank User For This Post WWW plugwash plugwash 107767391 peter_m_green_zyworld_com plugwash  
IP Logged
 
mart_the_spark
Re: Strange Ring Extension
Reply #12 - May 4th, 2004, 7:19pm
 
"isolate from multiple sources"
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: Strange Ring Extension
Reply #13 - May 5th, 2004, 1:50am
 
Andrew, the problem is there is no real protection when you just have crimped and taped connections, and JB's would technicaly need to be accesable, but they often are not. putting them in a chocbox or a jb is just doing the same required thing.
Back to top
 
Thank User For This Post 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: Strange Ring Extension
Reply #14 - May 5th, 2004, 1:52am
 
[quote author=mart_the_spark  link=1083576748/0#12 date=1083694778]"isolate from multiple sources" [/quote] 'isolate elsewhere' still not recommended!!  Shocked
Back to top
 
Thank User For This Post View members image gallery  
IP Logged
 
HM
Super Member
*****
Offline

Chief Turd Polisher
Posts: 5072


Total Thanks: 0
For This Post: 0


Gender: male

Re: Strange Ring Extension
Reply #15 - May 5th, 2004, 6:51am
 
[quote author=L.Spark  link=1083576748/0#13 date=1083718243]Andrew, the problem is there is no real protection when you just have crimped and taped connections [/quote]

Understood.

However if the crimped connections were made in the void under the 1st floor then presumably you could leave the crimpe unprotected anyway?

Andrew
Back to top
 

If you aren't always sure of the right answer don't take up a career in the bomb squad
Thank User For This Post  
IP Logged
 
rabbit_rabbit
Re: Strange Ring Extension
Reply #16 - May 5th, 2004, 7:01am
 
ALL connections MUST be within an enclosure - and regardless of voltage SELV as well. So if ya crimp or use terminal strips they MUST be enclosed - ya can get those small plastic boxes (ChocBoxes) from most vendors even SF do them! And the lids snap on and also come with screws to screw down so complies with "need for a tool" bit as well as cable clamps - quite a neat job really.

RR
Back to top
 
Thank User For This Post  
IP Logged
 
Pages: 1 2 
Send Topic Print