Thank you in advance for help with this mystery.
We detected a voltage in our hot tub, my wife detected a small shock.
My multimeter detects between 9-11v. The unit has a 10ma rcd which doesn’t trip. Nothing else on the circuit trips either. Even switched off it still reads the same voltage. Only if we remove the plug from the socket it returns to 0v.
An electrician has checked the circuit to the plug, changed the plug socket etc. He can find no fault.
The hot tub plugs into a plug that is a spur from a garage circuit.
He is stumped and so am I. I cannot think what else to check. Also just to add if we plug the unit into the main house circuit, the unit reads 0v.
Don’t really know what else to look at.