Strange wiring

[hologram]

I recently replaced a ceiling rose in the bedroom of my flat and found the wiring to be quite odd..

1 single black wire sheathed in grey
1 single black wire sheathed in grey

1 twin cable black/red sheathed in grey (black wire has brown sleeve on it )

This was wired both single black wires together connected to light neutral.
Red cable from twin cable to light live. black with brown sleeve to earth terminal on rose..

All the lights seem to work ok but this seems an odd system

 

[Spark123]

The only thing I'd be dubious about - is the black with brown sleeve actually an earth or has someone just popped it in there for somewhere to put it?
Apart from that it appears to have been wired in sheathed singles, not the normal way to do it nowadays but not that uncommon.

 

[Albert]

I would think that the black with the brown sleeve is the "switch live" and this is the cable that comes back to the rose from the light switch.

 

[hologram]

Untill I can get my tester on it I cant be sure its an earth but it is connected to an earth terminal,Also this wire traces back to an earth terminal on the light switch wall box...
Strange....


The Red is def live from the light switch

 

[sparkyspike]

What else is connected to the earth terminal at the back box?

 

[hologram]

Another twin core cable red going to switch black with brown sleeve going to earth terminal which I assume is going to another a light fitting in the next bedroom

 

[Taylortwocities]

That does sound like someone is using the earth terminal for a live conductor. Be very careful until you understand what's gojng on..

 

[hologram]

Just tested the black with brown sleeve at light switch and its def an earth.
Ive been in this flat 10 yrs and never had any electrical problems but this does seem a strange wiring circuit maybe its time for a rewire......

 

[sparkyspike]

It sounds like a live conductor has been used as a circuit protective conductor. Why the hell it's sleeved in brown is anyone's guess. Did you test the earth continuity back to the main earth terminal? It's very worrying the way the conductors have been identified. Do you have any photos?