"Martin Angove" wrote in message
...
Ooh, I was trying *so* hard to keep out of this one for a while -/

In message
ws.net,
":::Jerry::::" wrote:

"Andrew Gabriel" wrote in message
.. .

[big snips, anyway]

What happens instead is, "Oh, I wonder which appliance blew
the fuse?" Start trying them all in another circuit, and
eventually
BANG!.

Err, how many appliances are you plugging into a single outlet
?...

That wasn't the point. The point was that there are multiple
outlets on
a single circuit. Even with your 120V 15A radial design you might
have
half a dozen or more appliances protected only by the common fuse
at the
distribution board. When that fuse pops, how do you know which one
of
the appliances has caused the problem?

Who is talking about 110v supply, all the supplies I ever had have
been 240v 50Hz....


With our 240V 30/32A rings, 30/32A, 20A and 16A radials we are
allowed,
effectively, an unlimited number of sockets. My house has (ignoring
the
kitchen) 24 double sockets. Because it is relatively small, these
could have been (though they aren't) supplied by a single ring or
even a
single 30/32A radial. If the circuit fuse pops, that's a lot of
appliances to check.

Exactly, if one appliance caused the circuit protection to trip you
take the whole lot down, with a radial circuit you only take one or
two down - there is nothing to stop local appliance protection being
used at the plug - belt and braces without the huge step from 3 A to
30 A if some idiot does something stupid - nor the chance of every
appliance from the 'teas-maid' to the freezer (or computer...) being
taken down by a faulty table lamp.


If, on the other hand, a 13A fuse manages to correctly discriminate
with
the 32A MCB (unfortunately it won't always) then the job's a lot
easier.

So protecting something at a 15 A rating is less safe than doing
so
at 30 A when someone replaces the fuse in a BS1364 plug with a
bolt
or what ever, as has happened ?....


Well, I'm sure it *has* happened, but personally I've not come
across it
ever, and I do get to see a few plugs. It was slightly easier to do
in
the days of wire-it-yourself plugs, but in these days of moulded
plugs
it is difficult to get anything other than a BS1361 1" fuse to fit
into
the fuseholder.
snip

Anything the size of a BS1361 1" fuse will fit though...