On Mon, 17 Aug 2020 09:05:13 -0700 (PDT), wrote:

On Monday, 17 August 2020 16:59:34 UTC+1, Scott wrote:
On Mon, 17 Aug 2020 16:20:35 +0100, John Rumm
wrote:

On 17/08/2020 14:04, Cursitor Doom wrote:
On Mon, 17 Aug 2020 02:12:17 +0100, John Rumm
wrote:


If it were a BS1362 style fuse, the looking a bit to the left of the 3A
fuse curve would suggest that it might take 3A indefinitely:

http://wiki.diyfaq.org.uk/images/d/d...FusingTime.png


Yeah, here's a picture of the exact type he


https://images-na.ssl-images-amazon...._AC_SX355_.jpg

Probably fake - the end caps look too shiny to be Bussman

Here are some tell tails:

https://www.pat-testing-training.net...fake-fuses.php

(there is also more to a fuse than will it blow at an appropriate level
of overload. Actually having the capacity to interrupt the flow of
current, and not exploding in your face being some important ones!)

Seems there's even more leaway than I'd expected for extended
over-current tolerance. Perhaps we should never fit anything bigger
than a 10A fuse in a 13A plug? I think I'll toss out all my 13A fuses
to be on the safe side.

You could flip the argument, and say never fit anything other than a 13A
fuse. The purpose of the fuse (for any moderately recent appliance
anyway) is to provide *fault* protection to the flex - and a 13A fuse
will do that just fine.

The exceptions to this are some low quality multiway extension leads
where 10A would be more appropriate, or for historic appliances and
flexs, or cases where a manufacturer explicitly cites a smaller fuse.

I have seen this argument so many times before and have never
understood it at all. I acquired a supply of 2 amp fuses and fitted
them to various low current appliances, without any difficulties. How
anyone can argue that limiting the fault current is anything other
than a safety enhancement confounds me.

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?

2A fuses are certainly a little safer on low current loads, but they do not limit fault current, they merely trip faster at a given current & are thus less likely to permit a fire to start. They also have more chance of tripping before fire on an overheat overcurrent condition.

Thanks. I'm glad I am not going mad!