An rcd should only detect a current of around 30mA, while appliances can leak a couple of milliamps (up to 3.5 is acceptable, more for something like a cooker) onto the earth without much happening.
Adam
March 2009
Just wondering how voltage comes into this! If there is earth leakage it is a difference in current between the live and the neutral - this is what is detected by a residual current device. Where is this 17/19 V being measured - between what and what?
J
February 2009
I think it best to find out what is causing the earth leakage first,not knowing what voltage your supply is or what country you are in, continue to measure (with a friends help) the leakage voltage whilst you go around switching each individual item on the circuits off and hopefully you will come across the culprit, or culprits that are causing this, then you can investigate ways of improving the leakage by testing that individual piece of kit or simply remove / replace it.
Charlie
February 2009
It would be best to find what is causing it and take it from there. I would say it's most likely to be computer equipment or some kind of heater that is hard-wired, possibly a cooker.
Provided the voltage is below 50Vac it is acceptable; did you want to reduce it because you were worried about using IT equipment?
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