Spurs?

[HLMCEM]

Hi

Need advice regarding spurs etc.

Our conservatory gets its electrical supply from a cable run from an existing socket in the adjacent dining room. The socket in the dining room consists of 1 cable LNE for the dining room plus 1 cable LNE for the consevatory supply.

The supply in the conservatory consists of 2 x 13 amp wall sockets, 2 fused (3amp) junction boxes to wall lights.

Is the setup OK?, the supply running to the conservatory from the dining room is from a socket that is never used in the dining room. This configuration has been in place for about 10=15 years with no problem.

My main reason for bringing it up is to get clarification on what constitues a spur?

Hope I have made my comments clear

 

[sparkytim]

Hi

If this is all fed from a Ring final circuit then NO it is not ok UNLESS it is a Fused spur limiting the possible total load of the spur to 13 Amps

Limitations for an unfused spur off a Ring are 1 Double socket OR 1 single socket

 

[Technician]

Any one ring main can have the same number of unfused spurs connected

as there are sockets provided that the conductor size remains the same

to the spurs. (2.5 mm squared). The sockets can be either single or double.

Where a conductor size reduction takes place a fused connection unit must

be fitted. A smaller conductor can be used to power a spur provided that

the correct protective device is fitted and this also limits the number of

sockets that can be added.

My concern is that from your description, a trailing lead is powering installed

sockets in the conservatory from other installed sockets in the dining room.

If this is the case, the conservatory sockets need to be included in the ring

main and this is possible only if the total area of the conservatory and dining

room does not exceed 100 metre squared and the conductors need to be 2.5mm

squared cross sectional area.

Depending upon the number of sockets in the conservatory and proposed loads

it may be possible to connect these via an installed spur from the dining room

ring main.

Again, the 100 metre area rule applies.

I would then recommend that testing be carried out to ensure that the integrity

of the ring main has not been degraded.

For any of the remedial work, I am sure that other forum members can be

contacted to assist.

 

[Evans Electric]

Its not correct but its not the biggest thing in the world .

If,as you say , the first socket is not used , if its a single take it off and fit a spur . If its a twin ,take it off , fit a dual surface moulded box over it, fit a blank to one half and a 13A spur to the other side , which will feed your conservatory.

 

[HLMCEM]

Its not correct but its not the biggest thing in the world .If,as you say , the first socket is not used , if its a single take it off and fit a spur . If its a twin ,take it off , fit a dual surface moulded box over it, fit a blank to one half and a 13A spur to the other side , which will feed your conservatory.

Thanks for info, its a double socket in the dining room, so just to clarify if I remove the socket, replace with a dual surface box blank over one half, then take the original dining room supply cable plus the conservatory spur cable, wire into a 13 amp spur and fit to the other half of the box, this is OK?

 

[Doc Hudson]

Welcome to the forum, A spur is a branch off a ring circuit. Have we actually clarified, (have you proved), that the original circuit is a ring circuit. Not all sockets are wired as rings. What is the fuse rating at the consumer unit? If it is a 20A radial then there is probably no need to to anything. Did you say the dining socket only has two cables, one of which goes to the conservatory. You have got to prove exactly what the original circuit arrangement is in order to decide if or what needs to be done.

Doc H.

 

[HLMCEM]

It Comes off the Ring, protetcted by 30 amp fuse.

 

[Doc Hudson]

It Comes off the Ring, protetcted by 30 amp fuse.

But how many cables in the dining room? is this already a spur or is the dining room part of the ring?

Doc H.

 

[HLMCEM]

The dining room was an extension build apprx 22 years ago, checking the other socket which is in use ihe dining room, it shows three L N E cables, one of which I am sure feeds the unused socket, which indicates a Spur, am I rights? If thats the case does Evans Electric solution become viable.

 

[Doc Hudson]

The ring in the dining room ring can only feed one socket without any additional fusing. So as long as you do not try and keep a socket outlet at the unused position in the dining room, that currently supplies the conservatory, you could change it to become the fused spur as Evans Electrical suggests. So your existing dining ring will now go Socket in use -> Cable -> Fuse Spur{old unused socket} -> Conservatory power. Which will provided adequate protection for the conservatory cables. It would be wise to meter out the cables while the circuit is dead to confirm your routing assumptions are correct. Also ensure you double check polarity and earth continuity once you have done your alterations.

Doc H.

 

[Evans Electric]

Thanks for info, its a double socket in the dining room, so just to clarify if I remove the socket, replace with a dual surface box blank over one half, then take the original dining room supply cable plus the conservatory spur cable, wire into a 13 amp spur and fit to the other half of the box, this is OK?

Not exactly , you don't need the twin SSO so throw it away and cover the twin box with a dual box with a spur and a blank plate on it . That spur can now only be loaded up to 13A .

 

[HLMCEM]

Many thanks for your advice, I have just checked the wiring again on the unused socket in dining room , not much play on the cables hope they reach the connection in a spur, if they are not long enough, can I connect a fused spur into the conservatory cable inside the conservatory before any of the sockets in the conservatory, much easier for me to connect a fused spur there. Hope thats clear, if thats acceptable, could I retain the unused socket in the dining room.

Thanks again

 

[tom1]

if you want to keep the dining room socket fit a dule box fit a 13amp fcu and from load side supply a socket next to it which also feeds your conservatory