This was supposed to be a simple switch change where a previous sparks in the company had identified a faulty metal clad 2 gang grid switch module causing RCD trips. He had disconnected the feed wire from it and even attached a lable to it to ensure the correct module is replaced.
When we arrived the RCD had tripped.
A quick glance at the CU and local wiring showed this:
Apologies for the poor picture quality but hopefully the light patches on the 2.5mm² cables [nearest to CU] can be seen, this is a 32A ring final with 5 metal clad DSSO's and 6 pieces of t&e. IR test showed 25KΩ between any of the conductors.
The strange thing is each leg of the circuit, or combinations of several legs, measured between 25 to 30KΩ between any of the conductors despite ranging from 2 to 20 metres, also measuring at 250V or 1000V made very little difference.
The brown conductor seems to be stuck tothe sheath but the blue is as expected.
The other 3 circuits are fine.
When we arrived the RCD had tripped.
A quick glance at the CU and local wiring showed this:
Apologies for the poor picture quality but hopefully the light patches on the 2.5mm² cables [nearest to CU] can be seen, this is a 32A ring final with 5 metal clad DSSO's and 6 pieces of t&e. IR test showed 25KΩ between any of the conductors.
The strange thing is each leg of the circuit, or combinations of several legs, measured between 25 to 30KΩ between any of the conductors despite ranging from 2 to 20 metres, also measuring at 250V or 1000V made very little difference.
The brown conductor seems to be stuck tothe sheath but the blue is as expected.
The other 3 circuits are fine.
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