Lights tripped, fuse fine,lights not coming back on

[markharris]

Hello guys,
Got called round to an old ladys house tonight, she said that a lamp blew in her front room, so she changed the lamp, and now none of the lights work in the whole house. I checked her fuse and thats fine. She's happy tonight as she has lots of lamps working off sockets, and I'm back round there tomorrow afternoon. My fault finding skills are developing, and I'm wondering if anybody has any ideas on what the problem is, I had a quick look at the cables connecting to her ceiling light in front room, and all is fine...no loose connections, no signs of damage.

 

[DurhamSparky]

FUSE OR MCB???

as MCB can be in the Up/ON position and may actually be broken!! check the top of MCB against the earth bar with volt tester to see if thats the problem!!

p.s did you just recently qualify ??

 

[Guest123]

There must a blown fuse or tripped MCB somewhere.

Start at the CU by checking all terminations then with a voltage indicator start at the fuse/MCB and check at all fittings on the affected circuit.

 

[mechelec]

MCB or previously loose connection somewhere between MCB and failed lamp now open circuit. if MCB is ok check continuity of L-L, N-N and E-E between CU and light fittings

 

[markharris]

checked fuse on cu, and thats fine. I did a voltage check on circuit side of fuse and neutral, and got 230v, which is why this is really confusing. I am aware I'm going to have to start testing voltage at all the light fittings, but the one in the front room is just a switch wire and feed coming out of a hole in the ceiling, and I wasnt getting a voltage reading at that point. I was just wondering if anybody had experienced a similar problem, before I start having to test the whole circuit bit by bit,

 

[mechelec]

bad connection in JB somewhere. good luck

 

[markharris]

cheers mechelec, just baffles me that something like a blowing lamp can force a loose connection

 

[Noddy67]

just a thought, I was called into a job where the lights had gone. same; ccu was good but lights off. However it was an old rambling house and there was another separate/standalone MCB under the stairs. Luckily it was found really quickly but it could have been a nightmare.

good luck mate - know the feeling.

 

[mechelec]

cheers mechelec, just baffles me that something like a blowing lamp can force a loose connection

Fault current causing an existing bad connection to burn off going open circuit ??

 

[Des 56]

The symptoms people give of a problem are sometimes not exactly what has happened
If for instance a fault had occured in the fitting,the fuse blew and was then repaired and the lamp changed (because thats what they thought was the cause)there is possibility that the switch has self destructed when switched on, hence no switched supply at light and fitting fault
It could be any of the suggestrions already made

I dont think you will find a reason until the ladders and test gear come out

 

[pushrod]

just a thought, I was called into a job where the lights had gone. same; ccu was good but lights off. However it was an old rambling house and there was another separate/standalone MCB under the stairs. Luckily it was found really quickly but it could have been a nightmare.

.

Boy do i know that feeling, except i didn't find it quickly as it was under loads of coats

 

[simonatlondon]

I had a similar problem before. It was a broken neutral at the consumer unit. Where the stripped cable was, had broken and therefore no continuity of circuit. At the light fittings I got no voltage between line and neutral but I got 230v between line and earth. Check the neutral of the circuit is connected to the neutral bar properly. Good luck.

 

[bertt]

Hi,

If not too late I should try the next:


Ony if you are an Electrician.

1.Remove all bulb(s)from lamp in that room.
2.switch on/off for few times and evalute the switch condition(good or broken).
3.take CU voltage (probably 240v) and after inside bulb(s) and/or junction box?
(with switch ''ON'')....240v as well or less ?????

what about bulb (230V OR 12V/..60W) about landlord replacement did you check it?

broken switch and/or one bulb holder(E27/B22??) I think.

Thank you and good luck.

bertt.

 

[Rampantchilli]

I'm almost always confused by berts replys.

Id say you have a blown connection, check thoroughly and methodically, starting from CU as that's the beginning, the fault can only really between CU and first light

 

[Sparkie30]

Hi,

If not too late I should try the next:


Ony if you are an Electrician.

1.Remove all bulb(s)from lamp in that room.
2.switch on/off for few times and evalute the switch condition(good or broken).
3.take CU voltage (probably 240v) and after inside bulb(s) and/or junction box?
(with switch ''ON'')....240v as well or less ?????

what about bulb (230V OR 12V/..60W) about landlord replacement did you check it?

broken switch and/or one bulb holder(E27/B22??) I think.

Thank you and good luck.

bertt.

mate you are 2 and half years late with your response.