lighting fault

[growler]

hi. Have been trying to find a fault at my old mans house. It is old school rewireable fuses protected by an earth leakage trip. The fault is on the lighting circuit. Sometimes trips instantly when fuse is replaced, and sometimes it takes a minute. Nothing has been changed or altered in the house for years. Im scratching my head a bit and wondered how others would attack it. thanks for reading.

 

[nickblake]

Has it been raining down their sounds like water in an outside light , firstley remove all the light bulbs on the circuit and do a continuity test to ensure that the cpc are continuous through out the lighting circuit in question ,remove L and N from the board and do a continuity test between the L and the CPC then again N and the cpc then just do a continuity test across the L and N unless there are Pirs or external PIR lights outside these should give no reading then carry out the same tests using the Insualtion tester first test at 250 volts just in case there is something in circuit then increase the voltage to 500 and repeat the tests , i sound like a low insulation fault oh you will have to operate all the light switches during the tests to ensure the cables are ok , othere possible faults are burn out wirng in a pendant , rodent attack with rodent attached to cables causing a low insulation short fault low energy lamp

 

[Guest123]

When you say "earth leakage trip" does it look like this.....

Also do you have any test equipment available to you???

 

[Octopus]

Do you have any rodents.

Recently looked an issue which, at first was an occassional trip, then all of a sudden, instant trip. When located I found the cabling had been nibbled through - was expecting to see a dead animal - but no!