I live in a 5 room bungalow. The electric panel is in the garage. It one circuit breaker for lights, one for sockets, etc etc. Yesterday I disconnected a light in our porch ready for it being moved due to having a new door fitted. I switched off the trip, disconnected the cables, taped them up carefully and made sure they were safe. The switch for this light was off and has not been touched since.
Several hours later last night we were sitting in the living room and the light went out suddenly. I initially thought it was a power cut as there have been some recently due to weather. On further investigation only the lights in the living room and the kitchen were affected. Bedroom, spare room and bathroom all fine. I checked the circuit breakers – all on. I even checked the wires I disconnected for the porch light – all ok.
I haven’t got a clue what is going on now. Two rooms without lighting. Both on the same lighting circuit as every other room, protected by one circuit breaker which is ON.
Anybody got any ideas??

Mice ?

Can you trace the wires ?

Checked power at the switch?

Would something chewing through wires not cause a short and trip it out?
Not easily – up in loft.

No, I don’t have a meter. Or competence!

tripped RCD?

Not sure what you mean. Lighting circuit protected by one breaker for all of it. There isn’t RCD’s for individual rooms.

There might be a fused spur somewhere which feeds the affected circuit and that fuse has blown.

My guess would be that you knocked the “onward” wire on the lighting circuit and it lost connection later. Rooms between the CU and outside light are still working, rooms after it no longer have power.

When you say you taped up the wires – what did you do? keep all the wires together that were in the same terminals and just wrap in tape?
Lights are usually daisy chained in a radial circuit – power in to the light and power out the next light. I would guess your tape has come apart and broken the circuit to the next lights. The lights that still work will be in the circuit before the one in the porch.
As a very temporary measure you could get away with a chocolate block connector as long as its out of reach and nobody is going to stick their fingers in there. Not wanting to be preachy but if you dont have the equipment and knowledge to check that the circuit is actually dead before disconnecting terminals then I wouldnt be playing with it

Good call. I’ll terminate the wires in chock block as they were in the light.

Sorted now. Thanks to everyone who responded. Much appreciated. 👍

An ironic username for such a post..

Sorted now. Thanks to everyone who responded. Much appreciated. 👍

How???

Checked wiring from removed light. Although 3 of the earth wires were still taped together the tape had loosened enough (possibly due to cold outside air) and they weren’t all in contact with each other. Once the contact was remade the lights worked perfectly. Phew!

Although 3 of the earth wires were still taped together

Earth wires shouldn’t be necessary for the light to work, current should flow between live & neutral unless there’s a fault.

Although 3 of the earth wires were still taped together the tape had loosened enough (possibly due to cold outside air) and they weren’t all in contact with each other. Once the contact was remade the lights worked perfectly. Phew!

That sounds more like luck than anything. The earths don’t really do anything in normal operation. They’re there for safety not function. Unless something is actually wrong you should physically be able to leave them in fresh air in most circumstances though doing so would be stupid.

Check your other connections.

Just out of curiosity, what colour are your ‘earth’ wires?

Just out of curiosity, what colour are your ‘earth’ wires?

+1

That was my thought on ‘earth’…

We had a house with an older panel. The earth was very important and disconnecting it caused a problem.
With everything turned off touching negative with an earth would trip everything. We sold the house but just presumed it was an old more sensitive system.

Touching neutral to earth on any RCD protected installation will trip the RCD, even if the individual circuit breaker is off.

You don’t have a “negative” on AC and it’s actually quite dangerous to think of it in that sense.