fused spur cable length???

[scott.rick]

i recently had to add a spur from a ring to supply a item of fixed equipment. I took the supply from a socket into to a switched fused spur and placed the necessary fuse for the equipment directly after the socket then a 10 meter cable run to a flex outlet connection unit then a 0.5m flex cord on the item of equipment.

My QS now tells me that the run is only allowed to be a maximum of 2 meters or else the spur must be changed to a ring and the socket i took the feed from must be re-configured to allow this. He claims this is stated in the regs but i have never heard of this?? i have always thought that provided the voltage drop is not too much and the resistance is within the max zs for the protective device etc then this is acceptable.

has anyone else come across this or if its in the regs can you tell me where it is please??

 

[JulianC]

I've never come across it in the regs. either. As you say, as long as volt drop and Zs are within limits, I don't see what the problem is.

 

[davelerave]

i'd say the 13a spur should preferably connect directly to the appliance 'power cord'

maybe he's referring to 2m distance for isolation of the appliance?

 

[simonspark]

I think your QS should go back to JI

 

[ezzzekiel]

something to do with half length of ring cant remember but its there somewhere

 

[simonspark]

OOps. Unless the item is a requires alocal means of isolation. But even so, you do not have to reconfigure to keep it on the ring

 

[pennywise]

Maybe it's to do with spuring off a spur. If the guy wants the means of isolation within 2m, the current spur would count as the single spur off the ring the new position would be the second, probably wrong. Think the QS just wants the means of isolation closer.

Having looked again think he does want you to make the first fused spur you put in part of the ring and the second closer flex outlet the spur from the ring and replace the plate with a switched fuse spur.

 

[simonspark]

If you look at the back of the 17th, they have all kinds of nice little drawings regarding radials, ringgs and spurs. Spider sysstems are now officially ok and you can wire sockets in 1.5 twin and earth. Nothing about max length of run for a spur in relayion to the lenghth of a ring final circuit though

 

[scott.rick]

he cant mean he wants a means of isolation closer to the fixed equipment as the switch is only 0.5m from it?

does this mean that nobody has ever heard of a min / max cable length for a spur i spoke to a few people who are currently teaching the regs and they have not come across it.

also its not a 13amp spur as its supplying an item of equipment requiring only a 2 amp fuse i have come from the socket into the switched fused spur containing a 2amp fuse then out of that in 1.5mm t&e cable.

 

[davelerave]

i don't think long runs of cable from spurs is a great idea myself

i think the spur should be close to the appliance


if long runs were allowed you could have wiring all over the place going back to spurs

 

[Sintra]

Lengths of unfused spurs off a ring final circuit should not generally exceed 1/8 the cable length from the spur to the furthest part of the ring. OSG p54

This is what i can find on the subject but this is for an unfused spur.

 

[Sintra]

he cant mean he wants a means of isolation closer to the fixed equipment as the switch is only 0.5m from it?

does this mean that nobody has ever heard of a min / max cable length for a spur i spoke to a few people who are currently teaching the regs and they have not come across it.

also its not a 13amp spur as its supplying an item of equipment requiring only a 2 amp fuse i have come from the socket into the switched fused spur containing a 2amp fuse then out of that in 1.5mm t&e cable.

It is a flex connection unit that is 0.5M away not a switch.

 

[scott.rick]

its not an unfused spur tho its a switched fused spur off a ring and that is different plus the regs only say max number of outlets spured off a ring unfused, isnt it that if its fused you cant put as many as you like as long as it doesnt exceed total fo that cable and protection???

 

[scott.rick]

It is a flex connection unit that is 0.5M away not a switch.

its a switched connection unit!!

 

[Sintra]

Then i see no problems.