I went to a smart home today; the client said the main rcd keeps tripping, so I opened the CU and done a IR. Switched mcbs off and located the earths for the kitchen ring and got 0.00meg ohm between L-E.
As I know; new regs, it's 1meg min for 230v, so I located the neutral and the same reading from the out going line conductors to the separated neutral conductors from the common neutral bar as this is indicating a dead short.
Why does the mcb not trip and the rcd only trips every now and then? Is it because 500v is a higher presure test than 230v? There was 3 other circuits on this fuse board like this, I'm not used to working in a smart home any ideas people?
Also the CU used to be in the kitchen and the consumer unit was moved to upstairs and the client said all the joints are behind the wall and plastered over. I think there is a cable crushed somewhere or a bad joint behind that wall.
The client said put rcbos in to see what one trips then we will narrow it Down, but I said to the client there is a problem with the wiring with the insullation resistance, the client is an electronic engineer so he said just do that. T
Thanks for your help people.
As I know; new regs, it's 1meg min for 230v, so I located the neutral and the same reading from the out going line conductors to the separated neutral conductors from the common neutral bar as this is indicating a dead short.
Why does the mcb not trip and the rcd only trips every now and then? Is it because 500v is a higher presure test than 230v? There was 3 other circuits on this fuse board like this, I'm not used to working in a smart home any ideas people?
Also the CU used to be in the kitchen and the consumer unit was moved to upstairs and the client said all the joints are behind the wall and plastered over. I think there is a cable crushed somewhere or a bad joint behind that wall.
The client said put rcbos in to see what one trips then we will narrow it Down, but I said to the client there is a problem with the wiring with the insullation resistance, the client is an electronic engineer so he said just do that. T
Thanks for your help people.
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