Just popped in to a friends house on the off chance that I could quickly remedy some none working lights before heading off to work. Unfortunately it was all a bit odd!
Over the past 2 years the ground floor lights have stopped working perhaps 3 times. They stop for either days or weeks then start working again.
None of the ground floor lights are working at present, so I started at the origin, I.e the CU. There was 240v on the line conductor (to earth) leaving the RCBO, but also 240V on the neutral conductor (to earth) leaving the CU. I realise it's unlikely to be a faulty RCBO, but I have come across a faulty protek MCB before, along with a faulty chint RCD. Only 2 faulty breakers in the past 10 years, as it's nearly always something else that's at fault. I'm only mentioning this to explain why I dived in with 'faulty breaker', plus I was hoping for a quick fix.
However, in the meantime they all started working and there was no longer 240V on the neutral terminal of the outgoing RCBO. All I had done is take the lid off of the CU and switched a few light switches on and off.
As stated earlier i considered a faulty RCBO, so I put the ground lights on a different RCBO. They then all stopped working again, and there was now 240V on the outgoing neutral terminal of this RCBO (along with 240V on the line). I put them back in the original RCBO and they all worked again.
Also, the test button on the RCBO's didn't work when there was 240V on both the line and neutral, when this cleared the test button worked.
Also, the test button didn't seem to work on the spare RCBO's that had power going to them, but no outgoing conductors in place. However, they did work on one of the RCBO's that was spare (without conductors). I checked the busbar and it was correctly in place for all RCBO's.
Ground lights are now switched off and I'll return, but I'm embarrassed to say I really can't think of what to do. Usually, a fault shows up, I break the circuit down, find it and fix it, but this is different to usually. Any suggestions?
Over the past 2 years the ground floor lights have stopped working perhaps 3 times. They stop for either days or weeks then start working again.
None of the ground floor lights are working at present, so I started at the origin, I.e the CU. There was 240v on the line conductor (to earth) leaving the RCBO, but also 240V on the neutral conductor (to earth) leaving the CU. I realise it's unlikely to be a faulty RCBO, but I have come across a faulty protek MCB before, along with a faulty chint RCD. Only 2 faulty breakers in the past 10 years, as it's nearly always something else that's at fault. I'm only mentioning this to explain why I dived in with 'faulty breaker', plus I was hoping for a quick fix.
However, in the meantime they all started working and there was no longer 240V on the neutral terminal of the outgoing RCBO. All I had done is take the lid off of the CU and switched a few light switches on and off.
As stated earlier i considered a faulty RCBO, so I put the ground lights on a different RCBO. They then all stopped working again, and there was now 240V on the outgoing neutral terminal of this RCBO (along with 240V on the line). I put them back in the original RCBO and they all worked again.
Also, the test button on the RCBO's didn't work when there was 240V on both the line and neutral, when this cleared the test button worked.
Also, the test button didn't seem to work on the spare RCBO's that had power going to them, but no outgoing conductors in place. However, they did work on one of the RCBO's that was spare (without conductors). I checked the busbar and it was correctly in place for all RCBO's.
Ground lights are now switched off and I'll return, but I'm embarrassed to say I really can't think of what to do. Usually, a fault shows up, I break the circuit down, find it and fix it, but this is different to usually. Any suggestions?
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