On 01/01/2020 14:54, Scott wrote:
On Wed, 1 Jan 2020 14:39:45 +0000, Mike Clarke
wrote:

On 01/01/2020 13:07, Scott wrote:

Okay, but any sensible person would replace like for like. You could
say the same about 3A fuses.

That works on the assumption that most people are sensible.

There are many who would happily keep trying the next larger size fuse
until it 'worked'.

So all appliances are designed to be safe with a 13 amp fuse?

Yes

The flex on the lamp I bought from John Lewis does not look to me that it
could carry 13 amps but I could be wrong.

See the example I posted higher up the thread.

Contrary to common expectations, that flex is likely to be
conservatively oversized when protected by a 13A fuse.

Fuses can be called upon to provide fault current protection and/or
overload protection.

In the case of a lamp there is no likely or plausible situation that
would result in a significant and prolonged overload, since the largest
lamp it is designed to take would probably be a 100W incandescent bulb,
and that has a maximum draw of under half an amp.

So the fuse only has to worry about fault protection.

(also remember, if you plug that lamp in Germany, it will have only a
16A MCB in the consumer unit protecting it)

I won't be trying it out.

If you read up on the concepts of fault currents as opposed to overload
current, you might be reassured.

Fuses can be used to provide protection for either, but in most cases[1]
for a modern appliance they are only required to provide protection
against fault currents. (The appliance itself should include any
protection required to mitigate against for overload current, should
that be necessary)

http://wiki.diyfaq.org.uk/index.php/...oad_curre nts

[1] Once exception being multi socket extension leads.

--
Cheers,

John.

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