Spurs on lighting circuits limited?

I've read somewhere that there are limits on the number of spurs allowed on socket radials, but does this apply to lighting circuits?
Or can I have a central spine with several radials going off for the lights and/or switches in various rooms, more than 50% on spurs?
[george]
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On 14/01/2018 16:37, George Miles wrote:

Lighting is normally wired as a radial circuit using 1mm or 1.5mm T&E that is protected buy a 6A MCB - therefore the word spur is not applicable to such a circuit.
So basically you can wire it up however you want (voltagedrop and PSC apply)
--
Adam

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On 14/01/2018 17:02, ARW wrote:

With sockets, there are limits on spurs from ring circuits, but not on the number or arrangement on radials IIRC.
SteveW
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On 14/01/2018 20:45, Steve Walker wrote:

True. So with a 2.5mm ring you are allowed one unfused spur for every point on the ring.
Note that a 4mm 32A radial has the same rules ie a 2.5mm unfused spur from the 4mm circuit is generally limited to the same regs.
Now a 20A 2.5mm radial only uses 2.5mm T&E and therefore cannot have an unfused spur.
I know many an electrician that is totally against the use of unfused spurs - however used correctly there is nothing wrong with them (and anyone who did a newbuild or a rewire with lot's of unfused spurs is probably mad)
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Adam

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What's wrong with unfused spurs on a radial socket circuit? I would think fused spurs are annoying because the houseuser might not find the fuse- you expect a fuse at the consumer unit or in the appliance's plug.
[george]
n Monday, January 15, 2018 at 7:10:55 PM UTC, ARW wrote:

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On 15/01/2018 20:46, George Miles wrote:

On a 20A radial, there is (generally[1]) no such thing as a spur, since the circuit can branch in any topology you like.
With a 32A radial with 4.0mm^2 backbone, then you are back to the same rules as for a 32A protected ring.
[1] I suppose you could take an unfused spur in 1.5mm^2 T&E, but only if its installed to method C
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On 14/01/2018 16:37, George Miles wrote:

No, radial circuits can have as many branches as you require.

Yes, whatever works for the circumstances.
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John.
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