Circuit breaker problem.

Soldato
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So all I did was switch the circuit breaker off (for lights). Then tried to turn it on again and it wont stay on.

The actual lights were switched off at the time as well.

I have had trips before but was always an obvious reason such as water leakage, blown bulbs, blown fuses, or overloading an extension cord (yep done that once).

But in this case the lights were off, all I did was turn it off and tried to turn it on again.

I am guessing the breaker itself is broken, so probable callout?
 
Soldato
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I think I'd be removing all the bulbs to see if that shows an earth leak somewhere ? (obviously no bathroom fan on it),
e: switch plates maybe too and disconnect feed.
 
Soldato
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Ok so an earth leak can happen even when the bulb is turned off?

Its only two bulbs, there is actually two light circuit breakers, this one is just for living room and bedroom, but it is a pain for me to get to the bulbs, so didnt want to do it unless had to.
 
Soldato
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they're single throw switches and one side of bulb is negative, if fitting had broken down and somehow touching earth, or the switch itself is leaking to earth removing bulbs may identify circuit ... next would be the switch plates and disconnecting the switch - more involved (they're not dimmers? which can create current imbalance.)
 
Soldato
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Turn the main switch off (plus all RCDs etc), and all the sub ones.
Switch the main back on then add them back individually

You probably triggered one of the protection circuits (RCD probably) and it needs to be reset as well
I did already try the turning the main one off hoping it would do a reset but not all of the sub ones, will try this and also what jpaul said after with removing bulbs.

The bit that confuses me if the circuit is leaking to earth why wouldnt it trip before I turned it off.

Seems the lights dont have a RCD.

Layout

Sockets - Shower - RCD master (green) Lights - Lights - Immersion - Oven - Master (double switch)

I will do all of them one at at time from left to right turning off, then right to left turning on.
 
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Soldato
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I did them all one at a time, and its still tripped. The others all turned back on fine.

It was slow but not really slow, didnt see your post till I done dLockers.
 
Soldato
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Why did you turn it off to start with?
I still had 25w of unaccounted for electric usage when checking on my IHD, so I flipped the switches to find what was using it (it turns out is my immersion, when thats off on its power switch its using 25w unless disabled on circuit breaker).
 
Soldato
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(ups with their capacitors are renown for tripping rcd's)

but from what you are saying rcd has not flipped (everything other than lights are working) and when you turn lights on it is only their (current not rcd) circuit breaker that won't remain on, the rcd does not trip.

to my mind you would have to have a short at a light bulb and a failing light switch toi explain that,
but removing bulbs might help - does light circuit breaker still trip with bulbs removed.
 
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I still had 25w of unaccounted for electric usage when checking on my IHD, so I flipped the switches to find what was using it (it turns out is my immersion, when thats off on its power switch its using 25w unless disabled on circuit breaker).

Thats dodgy, has someone tapped into the circuit for something else? Have you checked everything works still with it off at the circuit board. Something like a bathroom fan (depending on location of tank) could be wired into that circuit.
Or a heating pump or similar
 
Soldato
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(ups with their capacitors are renown for tripping rcd's)

but from what you are saying rcd has not flipped (everything other than lights are working) and when you turn lights on it is only their (current not rcd) circuit breaker that won't remain on, the rcd does not trip.

to my mind you would have to have a short at a light bulb and a failing light switch toi explain that,
but removing bulbs might help - does light circuit breaker still trip with bulbs removed.
The RCD seems only linked to sockets and shower, they are green.
The rest are red and dont have an RCD next to them just the mains switch. I may have misunderstood things, but I assume the colour coding is to show whats linked to the RCD?

I did try it again much slower and still the same problem ,but I didnt try disconnecting the bulbs or the wiring from the light switches.

I have noticed when comparing the switch to the working one next to it, the click is much louder and it also feels like it has less resistance. So the switch actually sounds different. I havent removed bulbs yet but I guess should try as will feel stupid if someone comes and it works with no bulbs.
 
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Soldato
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Thats dodgy, has someone tapped into the circuit for something else? Have you checked everything works still with it off at the circuit board. Something like a bathroom fan (depending on location of tank) could be wired into that circuit.
Or a heating pump or similar
Yeah it all works, I dont use the immersion heater so not a big deal having that off. I wouldnt rule out tapping, as after all I live in a flat. But my usage on all other circuits seems to add up, that was the only abnormality.
 
Soldato
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Probably the timer on the immersion tank depending on its age.

As for the trip turn the mains off. (big red switch) then flick the switch back up now turn mains back on.
 
Soldato
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Probably the timer on the immersion tank depending on its age.

As for the trip turn the mains off. (big red switch) then flick the switch back up now turn mains back on.
Already tried the big red switch three times now :( It doesnt even stay up with the red switch off (should have mentioned in first post),.
 
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Soldato
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(ups with their capacitors are renown for tripping rcd's)

but from what you are saying rcd has not flipped (everything other than lights are working) and when you turn lights on it is only their (current not rcd) circuit breaker that won't remain on, the rcd does not trip.

to my mind you would have to have a short at a light bulb and a failing light switch toi explain that,
but removing bulbs might help - does light circuit breaker still trip with bulbs removed.
The bulbs are now out, so thats been ruled out, I think it was unlikely as the switches been off prevents power getting to them, and it failed when I toggled the switch not when using the lights.
 
Soldato
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It's possible the trip has failed but unlikely, potentially a borrowed neutral issue, do you have a multimeter?
 
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