On 29/12/2017 12:51, Andy Burns wrote:

That way you've got 30mA of allowed leakage per circuit, rather than
30mA combined for half (or all of) your circuits.

cough 15 mA, if that. RCDs need to trip by their rated current and
should pass half their rated current, but some only just manage that.

So a 30 mA nominal RCD must trip if there's 30 mA leakage. It should
just allow 15 mA leakage. Some RCDs can be close to the 15 mA limit
so it's best to keep a comfortable margin below 15 mA to avoid
nuisance tripping.



--
Graham Nye
news(a)thenyes.org.uk