Strange reading when testing

[Welsh_sparky_21]

Got a call out to a job, drainage company had plugged a socket tester in and said to client there was an issue and they couldn’t do the work until it was resolved. Plugged my martindale in and everything seemed fine. Done a ZsRCD on the sockets and was getting 4.21 ohms, done a ZsRCD on cooker circuit and was getting a very high reading also. Tested the upstairs sockets which was on the other rcd and got a very high reading also. When doing a ze at the db I got 0.05, and my r1+r2 for the socket circuit was 0.28 ohms. Checked all connection within consumer unit and all very tight, even tried swapping over the neutral going from main switch load to the neutral bar and no change. Now when I do a zline test on these circuits I got 0.19 for the cooker and 0.48 for the sockets. It’s a metrel test kit I was using that’s why I was doing a ZsRCD test as to not trip rcd, anybody any ideas?? I know it’s a long post, rcd tripped within the times required also. Only thing I didn’t rule out which I thought of after was maybe the main switch neutral side starting to go faulty? Hence the high reading, didn’t think to check that at the time but

 

[EddieB]

Got a call out to a job, drainage company had plugged a socket tester in and said to client there was an issue and they couldn’t do the work until it was resolved. Plugged my martindale in and everything seemed fine. Done a ZsRCD on the sockets and was getting 4.21 ohms, done a ZsRCD on cooker circuit and was getting a very high reading also. Tested the upstairs sockets which was on the other rcd and got a very high reading also. When doing a ze at the db I got 0.05, and my r1+r2 for the socket circuit was 0.28 ohms. Checked all connection within consumer unit and all very tight, even tried swapping over the neutral going from main switch load to the neutral bar and no change. Now when I do a zline test on these circuits I got 0.19 for the cooker and 0.48 for the sockets. It’s a metrel test kit I was using that’s why I was doing a ZsRCD test as to not trip rcd, anybody any ideas?? I know it’s a long post, rcd tripped within the times required also. Only thing I didn’t rule out which I thought of after was maybe the main switch neutral side starting to go faulty? Hence the high reading, didn’t think to check that at the time but

Hi there, this is an interesting post and I have no idea but by the looks of it nobody else has, did you get it resolved ?

 

[Brother Blue]

Carry out a high current Zs test using the alternative test method and see what result you get.

By alternative test method I mean have the RCD open, connect L to CPC at the far end of the circuit and do a high current Zs test between the incoming (energised) and outgoing L terminals.