Spurs Off Ring Final Circuit

[steve100]

I have a query around installing a socket outlet spur off a final ring circuit in a domestic installation which isn’t protected by any RCD’s at the DB. My understanding is that to comply with the current regulation the cable installed in the wall would need to be in the prescribe zones (which it would), secondly it would need to be buries in the wall more than 50mm, which isn’t possible. I could install a RCBO at the DB for this circuit or enclose the cable in metal conduit (which would be more expensive), however my question is would it be possible to install a RCD socket outlet at either the end of the spur or the socket outlet I’m taking the spur from, would this provide the additional protection from shock required against accidental damage to the cable of the spur? I was told this would be possible, but I thought RCD Socket outlets only protect the the user of equipment from damage.

However I presume, if I wanted to run a spur of the ring to supply an outside fix light, I could install a RCD FCU next to the socket outlet I wanted to run the spur from and then run the cable to the light within the allocated zone and the cable would be protected against accidental damage between the RCD FCU and the light is that correct?

 

[telectrix]

yep. fit a RCD FCU adjacent to the socket you are tapping off, then both your cable and the new socket are RCD protected. an alternative with old CUs is to come off the RFC fuse in 4mm or 6mm to a RCD mounted adjacent to the CU. divert the 2.5mm L and N legs to RCD. then you protect all the RFC

 

[Deleted member 26818]

The RCD sockets would only provide protection for the equipment plugged into them.
If as Tel says, you were to spur off the ring using an RCD FCU, you would then protect both the cable and the socket.