On Thu, 10 Apr 2008 02:11:54 +0100, John Rumm
wrote:

With the RCD in the house, you make it difficult to avoid having the
feed to the freezer sharing a RCD with other devices, hence the
implications of a trip are worse.

Thanks. It seems that there are pros and cons to each way.

The advantage of having the RCD in the garage is that you can wire to
keep the freezer on if something else trips. However, I wonder about
moving the freezer inside when I get round to decorating the kitchen
and hbow often do RCDs trip anyway?

The advantages of having the RCD in the house a
1 the whole cable is RCD protected in case of accident
2 if there is a trip, I would not have to manually wind up the garage
door to reset the RCD... of course, that assumes I am not in he
garage when it happens. If I were in the garage with the door shut
when it tripped, that would be different again!

The fuse in the house is also highly unlikely to trip if sized
appropriately for the submain.

The fuse would be 30A for 6mm^2T&E but I would connect that to a 2-way
CU in the garage with smaller MCBs, only the garage CU would not have
a RCD, so the garage circuits would still be fused appropriately.

I suppose that I also need to measure the length of the cabel run to
make sure that if the RCD is in the house, all the disconnect times
are still within limits?

The only time is it likely to be a factor is if your earth loop
impedance is marginal in the garage. In which case you would be better
off making the garage a TT install in its own right.

I can't remember how long the cablet o the garage would be exactly but
definitely less than 10 metres. It's just I like the idea of that
cable being RCD protected in case someone knocks/drills/drives into
the conduit carrying it. How resilient is heavy duty plastic conduit
anyway?

Thanks again.