Cabling procedure for adding a FCU to ring main?

[alan333]

Hi,

My garage currently has 4 double sockets on it's own ring main circuit from the CU, all neatly tucked away in one approx 8 foot length of what I think is called dado trunking (big trunking one often sees surrounding office or hospital walls, which one can screw sockets/switches etc straight on to the front face). The sockets are for general light use of small power tools, the freezer, a radio etc. I'd like to add a bench light switch to the trunking. I intend to fit a FCU to the ring and obviously an appropriate sized cable supplying the light.

What's the correct way to connect a FCU to the ring main if there are no cable length constraints? Should it be installed as if its an additional socket, ie with both supply cables connected to its supply side, or should it be fitted as a spur from the next socket, ie that socket would have three cables on the supply side and the FCU only one supply cable?

TIA

 

[EFLImpudence]

Either way is fine. It depends on location and cable route.

 

[PrenticeBoyofDerry]

What's the correct way to connect a FCU to the ring main if there are no cable length constraints? Should it be installed as if its an additional socket, ie with both supply cables connected to its supply side, or should it be fitted as a spur from the next socket, ie that socket would have three cables on the supply side and the FCU only one supply cable?

You can do it either way: I prefer to maintain the ring final, but you can take a spur from a socket outlet.

 

[alan333]

Thanks guys. There's no problem with cable route/lengths etc since all sockets are within a foot or two of each other. I'll 'add' it rather than 'spur' it.

 

[PrenticeBoyofDerry]

Thanks guys. There's no problem with cable route/lengths etc since all sockets are within a foot or two of each other. I'll 'add' it rather than 'spur' it.

It would also be my preference. Do you know how to extend a ring final and do you have test equipment to prove it has been done correctly and safely?

 

[alan333]

I understand how a ring works, just wasn't sure whether to spur or break into the ring. I don't have test equipment but a family friend will test it for me. Thanks