On Wednesday, 13 January 2016 16:48:06 UTC, wrote:
charles wrote:
In article ,
wrote:
NY wrote:
"Martin Bonner" wrote in message
...
Are US and European plugs capable of having a fuse fitted in them
No

or do
their appliances always blow the circuit (eg downstairs ring main)
What ring main? Everything is wired as (chained) radials. But yes,
the only fuse is in the consumer unit.

Are ring mains mainly a UK innovation, then? I hadn't realised that.

Yes, I believe it was basically a copper saving idea in the post 2nd
war years.

Personally I think the disadvantages outweigh the advantages, I always
install 20 amp MCB radial circuits in preference to ring circuits.

Some years ago a friend bought house which was wired that way. The
distribution board was big enough for a small factory.

You don't need many more MCBs, it's not like the continental system
where there is one MCB per circuit. The IEE 'rules' suggest a maximum
floor area per MCB with no specific limit to the number of sockets per
MCB. Basically you'd need two 20 amp MCB circuits to provide sockets
to the same sort of area that would be served by one 32 amp ring
circuit. The major advantage is that you never have to puzzle out
whether any particular socket is a spur off a ring or not and you
can't suffer from a 'broken ring' fault.

No, instead of an almost trivial broken ring you get a fire or dead or unearthed sockets.


NT