Bring lighting circuits up to regs

YTSOxford · Jan 18, 2009

Just 1st fixed a small extension and was just wondering the best way of bringing the lighting circuit up to the new regs. I usually do bigger jobs, where the boards are replaced with a 17th board or, i split the tails and have a new board for the new extension.
However in this case the extension is so small, as well as the price the work has been quoted for; the contractor wouldn't be up for a new cu. The ring is already on a rcbo 30ma, so thats fine, so for the lights can i just change the mcb to a rcbo aswell; or does this mean that the whole board has to be brought up to spec????

Cheers all!

WarrenG · Jan 18, 2009

For any work you are now carrying out you need to comply with the 17th Edition so therefore if you are working with a lighting circuit only and you are protecting the lighting circuit with an RCBO you would be complying with the 17th Edition.

I would also add, providing that all the earthing arrangements are adequate and that you have discrimination between any other RCD.

Guest123 · Jan 18, 2009

As the man said, you only need to concern yourself with the circuits you are working on to comply with 17th but, before you start check that all earthing and bonding is up to standard. Then issue the relevant cert MW, EIC etc.

lister · Jan 18, 2009

if the extension is small, can you not just spur off the ring, (3a bs1361 in a fcu), as done with most conservatories and alike, then you would be rcd protected and no need to go int cu.

YTSOxford · Jan 18, 2009

The ring main in the conservatory is spured to a radial already so didn't want to spur down again since there will be 6 wall lights in the room, overkill I know, but its what the customer wants. So I'd rather take the lighting back to the board.
Thanks for clearing that up about the RCBO. I'd been by an older spark that as soon as you touch the board you have to bring all the board up to regs... but then again he ain't 17th, just experienced so I tend to take his word for it, too often!

And the earthing visually looks good, but will test it as soon as.