Fast blow fuses

[DiyNutJob]

Can anyone please explain why some fast blow fuses use a ceramic package and some use glass? I can see the convenience of glass. But, why ceramic?

Also, I have a PCB protection fuse engraved with T1AL250V. I know what 1A and 250V are. What does the leading T indicate?

 

[333rocky333]

Could be wrong but i believe, a normal fuse is F and a Time delay antisurge is a T, the ceramic are usually rated for voltage like 250v and the glass ones a lot lower often only up to 50 volts.
Glass are LBC low breaking capacity, ceramic are HBC high breaking capacity
You would not want glass shattering in an appliance hence the ceramic

 

[EFLImpudence]

Mr.Google knows.

https://www.slimlab.net/mirror/fuse...s the rated voltage,of a lower voltage rating).

 

[DiyNutJob]

I have this stuck in my head from somewhere: that glass fuse is fast blow, compared to say those in a 13A plug. Any truth to this?

From the above link, I am guessing fast blows are further divided into different speeds.

 

[EFLImpudence]

 

[DiyNutJob]

My point is that all glass ones are faster blowing than the ones in plugs. So they are all fast blowers. I have just checked the 13a fuse on my vacuum cleaner. Is has no markings except BS1362 and some logos.

 

[EFLImpudence]

My point is that all glass ones are faster blowing than the ones in plugs. So they are all fast blowers.

Well, yes but that proves nothing.

Glass or ceramic is to do with the breaking capacity; not the speed.

It might be that all fast-blowing ones are glass - I don't know - but not all glass ones are fast-blowing.

 

[TimboTwo]

View attachment 261543

Don't know where you got that from EFLI, but Quick Acting is NOT Anti Surge.
Just saying

 

[EFLImpudence]

Don't know where you got that from EFLI,
Just saying

It was from the previous link I posted.
https://www.slimlab.net/mirror/fuse...s the rated voltage,of a lower voltage rating

but Quick Acting is NOT Anti Surge.

I am not sure of the definitions but does it not amount to the same thing?

 

[DiyNutJob]

Don't know where you got that from EFLI, but Quick Acting is NOT Anti Surge.
Just saying

The surge would be cut short. Relative to other available speeds, it's best at countering a surge.

Well, yes but that proves nothing.

It proves glass ones are fast blowing compared to the ones in plugs, unless you know a glass one that is slower blowing than the ones in plugs. I don't know but curious.

 

[RandomGrinch]

The difference between ceramic and glass fuses isn't to do with whether they are timed or fast blow.
(Plenty of timed glass fuses available!)
It is to do with the current breaking capacity that they can handle at their rated voltage.
Ceramic fuses have far better thermal and arc protection than glass ones (if you have ever broken open a mains fuse, the dust inside helps quench an arc).
Because of this, in an over current situation, a glass fuse may be rated for a break capacity of 35A, a ceramic may be rated at 100A.

 

[DiyNutJob]

Is there any good reason for a 1A ceramic fuse used for PCB protection?

 

[EFLImpudence]

Is there any good reason for a 1A ceramic fuse used for PCB protection?

Presumably it needs a high breaking capacity.


Some brown cars are very fast - but it's not because they're not red.

 

[RandomGrinch]

Is there any good reason for a 1A ceramic fuse used for PCB protection?

...and sticking with the car analogy, some might just prefer a Rolls-royce!

 

[DiyNutJob]

Presumably it needs a high breaking capacity.


Some brown cars are very fast - but it's not because they're not red.

Can 1A produce that much of an explosive power, or is the breakage expected from an external trauma?