"Lobster" wrote in message
...
Andrew Gabriel wrote:
In article ,
Lobster writes:
I want to fit an MK Masterseal weatherproof socket for powering garden
tools, and will be ordering it from TLC:
http://www.tlc-direct.co.uk/Products/MK56480.html

That one remains weatherproof when there's something plugged
in to it. If you won't be using it in the rain, there are
cheaper ones which are weatherproof only when nothing is
plugged in. If it's just for mowing the lawn, that's
usually good enough.

Many thanks for all the advice - notably the above which has saved me a
tenner (hadn't realised there were different grades available like this)!

So, taking advantage of the nice weather to fit it this afternoon. Am
curious about the instructions though. The back-box has two earthing
terminals - given that this is obviously a plastic box, when would they
be required?

The instructions are as follows:

"2.3.1 Sockets
In spur configuration we recommend feed cable of 1.5 sq. mm for the
single socket and 2.5 sq. mm for the double socket. If the unit is to
form part of a ring then incoming and outgoing cables must both be 2.5
sq. mm (with the double socket we recommend that the incoming and
outgoing cables can be connected to one socket each with a 2.5 sq. mm
bridging cable between the two sockets.

Use back box earthing terminals to maintain earth continuity where
required."

Which brings me to another query. This doesn't apply to me as I have a
single socket, but what on earth is the bit about using a bridging cable
in a double socket? Surely it can't mean that this is necessary for the
continuity of the ring to be maintained, or, apart from anything else,
it would be compulsory rather than recommended? (FWIW the double socket
is at:

http://www.timeguard.com/product/out...ets/outdoor-tw
in-gang-socket)

Just curious!
David

The two terminals are for use on high integrity, multi-computer
installations where the total earth leakage current is 10mA and above, as I
recall. The double socket probably comes without the necessary links/bridges
beteween the two 13A socket outlets. I wouldn't recommend the use of 1.5mm²
cable from a final ring circuit.
Regards