dlt27
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- Joined
- Jul 4, 2011
- Messages
- 196
- Reaction score
- 30
Sorry this is a long one!
I have been carrying out testing and Inspecting for about 10 years now, but haven't come across what I found at my Mum and Dads house. I rewired it about 12 months ago. It is an old stone house and was a nightmare to do.(It's a TT system fed off overheads and a split load MK board with an RCBO on the smokes.
I got a phone call yesterday with my mum saying that Western Power had turned the power off and when they put it back on half the circuits wern't working. I haven't dived into it yet because I haven't had time and also I thought I'd put it out to you lot to see if you had any ideas.
I went around there turned of all the circuits and reset the (bad)RCD then when I put the kitchen sockets on and it tripped. I thought faulty appliance somewhere tried fridge and it tripped the RCD then tried kettle and it did the same. Tried unplugging everything then tried one at a time however then couldn't get it to trip. I thought adding a load to the circuit was obviously finding the fault and I would megger it the next day because didn't have tester.
I went around this morning and Dad said basically anything they turned on tripped the (Bad)RCD . Sometimes the lights, sometimes the immersion, however it was totally intermittent. The funny thing was even circuits on the 2nd (Good)RCD was tripping the 1st (Bad)RCD ie cooker, but not all the time.
I tried all trip tests on what I thought was the (Bad)RCD and couldn't get it to trip, not even with a ramp test. Test button worked though. I thought I've got it. I tried same tests on 2nd (Good)RCD and it all tripped correctly, however when I tripped it I found it tripped the (Bad)RCD and also the RCBO I have got on the smokes. So basically what I thought was the good RCD tripped the 2 RCD's and the RCBO. I also found the test button on the faulty (Bad)RCD also tripped the RCBO, but didn't trip the good RCD. I've checked all neutrals of RCD's to check not mixed up or in wrong neutral bar etc. All is correct. I've checked neutral coming in to property is neutral etc and found PFC to be 0.21 live to neutral. I am going tomorrow to carry out a proper test ie. Disconnect all Neutrals and Lives of circuits and then try RCD tests, meggering etc.
To summarise what I can't understand is how all circuits in the board are tripping the bad RCD and RCBO like a borrowed neutral and why only intermittantly. Also why does so called good RCD trip bad RCD and RCBO when carrying out tests, yet bad RCD won't trip when tested.
The final thing is I don't understand why this as only happened since Western power turned the power back on, but I can't find anything wrong with supply. Any ideas would be much appreciated.
I have been carrying out testing and Inspecting for about 10 years now, but haven't come across what I found at my Mum and Dads house. I rewired it about 12 months ago. It is an old stone house and was a nightmare to do.(It's a TT system fed off overheads and a split load MK board with an RCBO on the smokes.
I got a phone call yesterday with my mum saying that Western Power had turned the power off and when they put it back on half the circuits wern't working. I haven't dived into it yet because I haven't had time and also I thought I'd put it out to you lot to see if you had any ideas.
I went around there turned of all the circuits and reset the (bad)RCD then when I put the kitchen sockets on and it tripped. I thought faulty appliance somewhere tried fridge and it tripped the RCD then tried kettle and it did the same. Tried unplugging everything then tried one at a time however then couldn't get it to trip. I thought adding a load to the circuit was obviously finding the fault and I would megger it the next day because didn't have tester.
I went around this morning and Dad said basically anything they turned on tripped the (Bad)RCD . Sometimes the lights, sometimes the immersion, however it was totally intermittent. The funny thing was even circuits on the 2nd (Good)RCD was tripping the 1st (Bad)RCD ie cooker, but not all the time.
I tried all trip tests on what I thought was the (Bad)RCD and couldn't get it to trip, not even with a ramp test. Test button worked though. I thought I've got it. I tried same tests on 2nd (Good)RCD and it all tripped correctly, however when I tripped it I found it tripped the (Bad)RCD and also the RCBO I have got on the smokes. So basically what I thought was the good RCD tripped the 2 RCD's and the RCBO. I also found the test button on the faulty (Bad)RCD also tripped the RCBO, but didn't trip the good RCD. I've checked all neutrals of RCD's to check not mixed up or in wrong neutral bar etc. All is correct. I've checked neutral coming in to property is neutral etc and found PFC to be 0.21 live to neutral. I am going tomorrow to carry out a proper test ie. Disconnect all Neutrals and Lives of circuits and then try RCD tests, meggering etc.
To summarise what I can't understand is how all circuits in the board are tripping the bad RCD and RCBO like a borrowed neutral and why only intermittantly. Also why does so called good RCD trip bad RCD and RCBO when carrying out tests, yet bad RCD won't trip when tested.
The final thing is I don't understand why this as only happened since Western power turned the power back on, but I can't find anything wrong with supply. Any ideas would be much appreciated.
