Fuse identification

[neate]

The fuse on my B&Q Multimeter has blown.

It's a short glass type. It's difficult to read the fuse type but I think it says on one end "F500L 250V". The other end might just say "F5".

What fuse should I get to be on the safe side?

Any advice would be appreciated.

 

[EFLImpudence]

Well, you need a F500L 250V fuse. of the same size

The 500 is 500 milli amps - half an amp.

https://www.swe-check.com.au/pages/learn_fuse_markings.php

 

[JohnW2]

The 500 is 500 milli amps - half an amp.

Yep, he needs a 500mA (0.5A) fast-blowing fuse of the same dimensions. The "F" indicates 'fast blowing' and the "L" indicates 'low breaking capacity'.

He probably also ought to get one 'rated' at 230-250V, although I don't really know what that means and wouldn't personally be too fussed about the 'voltage rating'!

Kind Regards, John

 

[333rocky333]

when I used to buy Glass fuses from RS most were rated at around 50 volt or less for some reason, though now they seem to only sell 250v rated ones, I put it down to them being made to a lower standard, breaking capacity and the glass shattering, in my experience Glass fuses seem rarely used over 50 volt, the Ceramic ones always seemed to be 250 volt rated.
https://uk.rs-online.com/web/p/cartridge-fuses/0563463/

 

[bernardgreen]

'rated' at 230-250V, although I don't really know what that means

It is the maximum voltage that will NOT sustain a plasma arc inside the glass tube after the fues wire ruptures. The plasma arc has to be extinguished otherwise the fuse is still conducting current and therfoe not done whau it was supposed to to. Plasma arc suppression is why many fuses are filled with sand.

 

[JohnW2]

It is the maximum voltage that will NOT sustain a plasma arc inside the glass tube after the fues wire ruptures. The plasma arc has to be extinguished otherwise the fuse is still conducting current and therfoe not done whau it was supposed to to. Plasma arc suppression is why many fuses are filled with sand.

In the case of a standard 'glass' fuse (which I imagine is probably what the OP has), is that, in practice, determined by anything much other than the length? Whilst it would obviously be possible to put something other than air inside the tube, I somewhat doubt (maybe incorrectly!) that they do that.

Kind Regards, John

 

[neate]

Another problem solved by DIYnot members.

Many thanks for all the advice.