On Tuesday, 18 August 2020 00:09:20 UTC+1, John Rumm wrote:
On 17/08/2020 22:09, tabbypurr wrote:
On Monday, 17 August 2020 21:57:17 UTC+1, John Rumm wrote:
On 17/08/2020 16:59, Scott wrote:

Why do you think the system was introduced with 1, 2, 3, 5, 7, 10
and 13 amp fuses unless a lower rated fuse had safety benefits?

For the limited cases where overload protection is useful. They
will all handle fault currents.

When the BS1362 plug system was introduced in '47 the plug fuse was
normally the appliance overload fuse, appliances mostly had little or
more often no other overload failure protection.

Agreed - hence why I mentioned it.

However a good deal of appliances (even then) don't actually need any
overload protection... So there is a danger that you could cause more
problems in the quest for "safety". (i.e. nuisance fuse blows, plugs
running warmer etc).

those aren't dangers. And putting a 3A fuse on a 2A load does not cause nuisance trips.


That has changed of
course, but there are still millions of appliances that have no
built-in overload protection and could benefit from it safety-wise.

I don't have a source of figures for how many are still out there. Do
you? Some, sure; millions perhaps?

I don't have a record of where they figures came from. But it's easy to come up with a very rough idea of the size of the issue.
1. How many substandard appliances have major retail sites sold?
2. How many PAT fail appliances are there per site? What proportion need & lack overload protection.
3. How many historic appliances are still in use? If you find just one per 63 people that's a million.


NT