Official light wiring rules?

[Cgehh]

Hello. In work we are adding in additional emergency exits into a lighting circuit. Is there any official rules about how many times you can spur off an existing lighting circuit (giving that the new additions wont be exceeding the value of the mcb). Or do you have to break the loop and wire the new lights into the loop and not spur off it.

And just another thing to settle, someone in work said that we can spur the live and earth but the neutral has to be made into the loop. Is he unwell or is that actually a thing?

Thank you

 

[radiohead]

Branch off or loop in, whatever. General wiring regulations apply. Ask your work colleague to provide the regulation he is referring to regarding the neutral.

 

[Dustydazzler]

Never heard of not using the N , I think he might be referring to not using a N from another circuit. Which is correct...

breaking the circuit / spurring off the circuit are all the same thing

 

[pc1966]

Look up "borrowed neutral" as that is probably the reference.

Basically you must keep the line conductor(s) returning via the same neutral that cabling provides. So if one circuit is isolated you do not find it becoming live due to power from another circuit returning via that unexpected route.

Also with RCBOs it will simply trip!

 

[Burtones]

It's a radial so you can branch off at any point as many times as you like. Your main two limits will be design current (so less than 6A or 10A depending on ocpd) and volt drop.