[Stevekimpton]

Checked with PAT unit and all OK but now sure one of the switches was occasionally shorting due to previous water ingress. Hair drier has sorted it. Thanks for your help anyway.
Still don’t understand how symptoms could persist with no neutral connection. Come to think of it I don’t understand how the high voltage spark to earth works when there is apparently no return path to the spark generator. Ho hum, it’s fixed anyway.

[Stevekimpton]

Thanks for that. I can get hold of a PAT unit that I know includes an earth leakage function and see what it says.

[Author]

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