Circuit protection (was: RE: Latest addition : PDP 11/70)

From: Carlini, Antonio <Antonio.Carlini_at_riverstonenet.com>
Date: Wed Aug 1 15:53:09 2001

>Of course this doesn't address the issue of devices which may fail
at a
>current draw that is substantially above the devices nominal draw
but
>less than the rating of the branch -- but then neither do
individually
>fused outlets unless you are careful to change the fuse each time
you
>connect a device -- which I've certainly never observed happening
in my
>visits to the UK. Instead almost all appliances and devices are
required

        In the UK, the MCB (circuit-breaker) or fuse in the
        main box is there to protect the ring main (the
        wiring in the wall). The fuse in the plug is there
        to protect the power cord. If the appliance
        needs protecting, it should have its own fuse :-)

        No fuse can guarantee that the appliance won't
        burst into flames - the appliance is supposed to
        have passed some minimal safety testing to
        make that unlikely - if it needs fuses to pass
        the test they'll be fitted internally.

        The remainder of the system does its best
        to ensure your iring won't burst into flames.

        Antonio
Received on Wed Aug 01 2001 - 15:53:09 BST