Thanks Peter,

Your description confirms that I have wired the element correctly.

Do you have any idea what could be causing the dryer to trip my RCCB?

I can only think it is heat related as it doesn't happen straight away and
then if I let the dryer stand for a while it will be okay for another 5
minutes.

My thoughts a

(i) Getting too hot so thermostat tripping - but I wouldn't have thought
that would have tripped my consumer unit - or am I mistaken.

(ii) Faulty element - could it be that it is shorting out when it gets hot.
Thing is, when cold both elements read 50ohms. When it has tripped and
still in a state to trip if turned on, both elements still read 50ohms.

Tomorrow I will try and check that none of the plumbing is blocked. We keep
the lint filter clean and I have checked the external vent hose - but I
guess it's worth checking inside. I assume I need to take the lower back
panel off.

Thanks again for the help.

Cheers,

Nigel