Hzatph wrote:

The 16 circuits have:

4 ring mains
2 power spurs (cooker, immersion heater)

^^^^^^^^^^^^^^^^
Prone to high leakage!

Try turning off / pulling the fuse for this and see if it helps.

If that does not find it then you are going to need to start testing the
wiring for each circuit with a megger.

--
Cheers,

John.

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