Attaching wall sockets in place of electric fire cable

[JohnW2]

Ah, ok - I guess the fcu can't be directly on the ring then, because there are only two cables going into the fcu, not three. One goes into the 'feed' terminals and the other into the 'load' terminals.

Correct. If it were part of a ring, there would be two cables connected to the 'feed' terminals (and one to the 'load' terminals'. The FCU is therefore probably a spur from somewhere. I suppose is still could be from that double socket if it, too, has cables to/from it going all the way up the wall (do you have solid floors?). Another possibility (although probably unlikely) is that the 'downstairs sockets' circuit is not a ring at all - but, rather, a 'radial' circuit. In that case, there would only be one 'feed' cable. What is the rating of the switch/MCB in your CU for that circuit (does it have something like 'B32' or 'B20' written on it)?

The fcu is definitely connected to the bare cable, as I wired it into a socket temporarily and checked it with a lamp. I also checked that the lamp went on and off with the other sockets in the room when the switch on the CU labelled 'downstairs sockets' was flipped, so I know they are on the same circuit (and it also went off when I turned off the switch on the CU labelled 'RCD' circuits, which I presume means they are protected by a circuit breaker).

Fair enough. As you say, that confirms both that the FCU is feeding the 'bare cable' and that the FCU is (somehow) connected to the 'downstairs sockets' circuit.

Does that mean it is a spur, after all?

As above, unless the 'downstairs sockets' circuit is a radial one (fairly unlikely), it must be a spur from somewhere - possibly from that double socket, possibly from somewhere else! If that's the case, then the FCU would be 'a spur off a spur', which is not compliant with current regulations. If it were a radial circuit, then there would be no compliance problems, provided the cables were of an appropriate size in relation to the breaker in your CU.

Kind Regards, John

 

[Andromedus]

The other wall socket also has it's cables running vertically up to the ceiling. (I found a photo we took of the living room as the house was still under construction, before the plasterboard went on. All the wall sockets/switches run vertically upwards behind metal conduit) Yes, the floor is solid.

The switch on the CU for that circuit is labelled B32. What does that tell me?

 

[JohnW2]

The other wall socket also has it's cables running vertically up to the ceiling. (I found a photo we took of the living room as the house was still under construction, before the plasterboard went on. All the wall sockets/switches run vertically upwards behind metal conduit) Yes, the floor is solid.

When you say 'behind metal conduit', are you just referring to 'capping' (rather than true conduit, which is metal pipe)? If so, that would not be adequate to remove the need for the cables to travel in the 'safe zones' - but, from what you've said, it sounds as if the cables probably are in save zones (vertical aligned with the socket and FCU)

The switch on the CU for that circuit is labelled B32. What does that tell me?

On it's own, it tells us little. If we knew for sure that the circuit was wired in 2.5mm² cable it would mean that the circuit was (or should be!) a ring.

Kind Regards, John

 

[Andromedus]

Yes, it's 2.5 mm cable. The metal covering the cable running from the fcu is indeed what I'd describe as a cap rather than a pipe. I've exposed a small section of it, and I don't personally think it would take much to hammer a nail through it. As you said, though, that is a safe zone anyway.

The cable running vertically upwards from bare cable, on the other hand, I'm guessing is not a safe zone because there are no switches, sockets or anything other than the cable on that vertical line. The metal covering that cable, though - I'm not quite sure as I haven't exposed it, although from the old photo I'd say it looks the same as the other one. So, probably not good. But slightly immaterial now, I'd have thought, as I'm going to be building the new wall over that section.

 

[JohnW2]

Yes, it's 2.5 mm cable.

OK - so it's hopefully a ring- but we still don't know where the FCU is spurred off that ring. If it were from that double socket (via a very circuitous route!) there would have to be three cables 'rising' from the socket.

The metal covering the cable running from the fcu is indeed what I'd describe as a cap rather than a pipe. I've exposed a small section of it, and I don't personally think it would take much to hammer a nail through it. As you said, though, that is a safe zone anyway.

Fair enough - but, as you say, that's probably not an issue for the socket (or FCU), since the cables are probably in safe zones, anyway.

The cable running vertically upwards from bare cable, on the other hand, I'm guessing is not a safe zone because there are no switches, sockets or anything other than the cable on that vertical line. The metal covering that cable, though - I'm not quite sure as I haven't exposed it, although from the old photo I'd say it looks the same as the other one. So, probably not good. But slightly immaterial now, I'd have thought, as I'm going to be building the new wall over that section.

Yes, as you say, not strictly compliant with current regs as it is now (not that you're under any obligation to upgrade it to current regs). but really a bit moot since you are going to 're-define' where the surface of that wall is!

Kind Regards, John