Is this classed as a spur off a spur

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I have a double socket which is definately a spur off the ring. I need to run power to a single light fitting. If i was to run 1.5mm from this spur socket to a 3 amp FCU then to the light is this classed as a spur off a spur.

If yes if i was to put a 13amp FCU before the socket , then run the 1.5mm cable from the socket to the a 3amp FCU to the light would this be ok.
 
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I have a double socket which is definately a spur off the ring. I need to run power to a single light fitting. If i was to run 1.5mm from this spur socket to a 3 amp FCU then to the light is this classed as a spur off a spur.

That would definitely be a spur off and spur, and even if it wasn't, it'd have to be 2.5mmsq conductors.

If yes if i was to put a 13amp FCU before the socket , then run the 1.5mm cable from the socket to the a 3amp FCU to the light would this be ok.

Yes, that'd be fine, and it will also allow you to use 1.5mmsq as it's protected by the 13A fuse, assuming no derating factors.
 
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That would definitely be a spur off and spur, and even if it wasn't, it'd have to be 2.5mmsq conductors.

Not that I would do it that way but consider that the 3A fuse would be providing overload protection for the piece of 1.5mm t&e.
 
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That would definitely be a spur off and spur, and even if it wasn't, it'd have to be 2.5mmsq conductors.

Not that I would do it that way but consider that the 3A fuse would be providing overload protection for the piece of 1.5mm t&e.

Indeed, and while 1.5mmsq would probably provide fault protection, I'd still prefer to see it in 2.5. Not that I like to see a spur off a spur at all... :LOL:
 
Isn't the CPC in a 1.5mm twin and earth 1mm? If so then it may be undersized from a fault protection POV anyway.
 
If yes if i was to put a 13amp FCU before the socket , then run the 1.5mm cable from the socket to the a 3amp FCU to the light would this be ok.
Just checking that what you are proposing is to connect the existing spur to the input side of the 13a FCU and then connecting the output side of the 13a FCU to both the socket and the input side of the 3a FCU? if so then this is ok.

I'd reccomend using 2.5mm^2 for any interconnections between sockets and FCUs. While 1.5mm is OK on a 13A fcu circuits get rearranged over time and people may not think to check cable sizes.
 
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If yes if i was to put a 13amp FCU before the socket , then run the 1.5mm cable from the socket to the a 3amp FCU to the light would this be ok.
Just checking that what you are proposing is to connect the existing spur to the input side of the 13a FCU and then connecting the output side of the 13a FCU to both the socket and the input side of the 3a FCU? if so then this is ok.

I'd reccomend using 2.5mm^2 for any interconnections between sockets and FCUs. While 1.5mm is OK on a 13A fcu circuits get rearranged over time and people may not think to check cable sizes.

Hi Plugwash i think the answer to your point is yes. I intend to take a 2.5mm feed off the ring into the 13a FCU. Then on the load side of this will be the socket outlet then from the socket to the feed side of the 3a FCU. The light will then be on the load side of this FCU.

I didnt write it clearly in my post but i was going to use 2.5mm at all points up to and including the feed into the 3a FCU then 1.5mm from this to the light fitting.

So i believe the design now allows that the lighting wiring is protected by a 3A fuse the wiring to and from the socket protected by a 13A fuse and the wiring to the 13A FCU also theoretically protected by this 13A as well as the circuit breaker.
 

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