simply answer no
the timer part of the fan is going to require a switched live.
this isolaor you refer to, is it a light switch?
you are going to need a 3core + earth.
use brown as a permenant feed, black as a switch feed(you need to oversleeve this with brown sleeving)
and use the grey as a neutral (this needs oversleeving with blue)
at the isolaor what cables other than those which come out to your fan are there?
chris gray, February 2010
