Spurs on lighting circuits limited?

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)

With sockets, there are limits on spurs from ring circuits, but not on the number or arrangement on radials IIRC.

SteveW

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

Yes, whatever works for the circumstances.

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)

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.

n M> > > >>> I've read somewhere that there are limits on the number of spurs

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.