Circuit protection (was: RE: Latest addition : PDP 11/70) - test-drb@ccmp.vtda.org

1 Aug 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