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ed-ectrician

Pretty sure it's ok but when wiring lights am I right in thinking rules for spurs and spurs off spurs off spurs are lots more lax than for power circuits. Thanks!!
 

darkwood

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Not sure i understand you, lighting circuits are usually radials with numerous points, i can only assume your relating to a ring main power circuit where the fuse rating exeeds the CCC of the cable but due to its ring nature it divides the current down both legs but when you spur of it you have to follow regulations as the cables of the spur are overated by the 32amp fuse so limitations are applied on how you can do this, unless its fused down with a Fused Spur
 

telectrix

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spurs off spurs on lighting would not be done by any spark with common sense. what's the bloody point ?
 

darkwood

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Im thinking this a terminology thing.... im hoping the OP means loop-in loop-out as appose to spuring... if i wrong hes lost me?
 

topquark

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Think he may be refering to more than one looped out device from a point.
 
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Adam W

I wouldn't word it as "lots more lax" at all - the cable still needs to be protected by an appropriate protective device.
 
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ed-ectrician

I explained badly my mrs was bringing me a steak so i was rushing!!! I mean you can get away with spider wiring system for example or take a feed for a set of downlights from a fitting half way along the lighting radial. Ta
 

Taylortwocities

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I just looked up the definition of "spur" in the BGB

It is defined as a branch off a radial or a ring final circuit.

I was taught that that "branch" was an addition to a radial and "spur" was an addition to a ring. Well, I never....

The difference is that you cannot have a spur off a spur on a ring final circuit but you can have a branch off a branch on a radial circuit.
Lights are radial circuits so you can add whatever you like, willy nilly and it's fine, providing you don't exceed the total maximum current for the circuit.

End of lesson, Now get out your rulers and pencils.
 

darkwood

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As long as you do your calcs for additional loading (inc diversity) and all complies then not a problem as well as ensuring you bring existing up to 17th ed' if not already as you are responsible for the whole circuit once you work on it.
 

sedgy34

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hes on about taking a lighting feed off a pendant then taking a feed off that feed and so on!! dont think he understands the terminology "radial"
to the op
if a lighting circuit is protected by its fuse theres no problem with it. nowt lax about it but with power you can do the same theory but you have to fuse it down.
but as tel says why bother
 

darkwood

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The difference is that you cannot have a spur off a spur on a ring final circuit but you can have a branch off a branch on a radial circuit.
Unless its a fused down then without going silly you are not limited as above and can have several fused spurs 'spured' off a ring circuit as long as you account for the loading on the circuit.
 
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ed-ectrician

Haha with chicken you gotta fuse down. 3 amp fcu before you get into your hotwing! This was a rump steak taken as an unfused spur off a big chunky cow haha!
 

Des 56

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I explained badly my mrs was bringing me a steak so i was rushing!!! I mean you can get away with spider wiring system for example or take a feed for a set of downlights from a fitting half way along the lighting radial. Ta

No need to come on here bragging
My sausages were nice as well :nono:
 

telectrix

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i took some chicken curry back to the chinese takeaway. i said this chicken is rubbery. the guy said thank you verry much. i said i can't eat this chicken, its. foul.
 
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