On Sun, 15 Nov 2009 12:07:09 -0000, Vass wrote:

My condenser tumble dryer keeps tripping the main 80A switch on my CU.

"Switch"? I think you mean RCD as normally the "main switch" in an CU
has now fault or overload function it is just a switch.

Assuming that it really is an RCD the the chances are that the dryer
has an earth leakage fault, this is fairly commmon. Probably have to
repalce the heating elements.

--
Cheers
Dave.