What is the difference between F5AL250V and F5L250V fuses?

In the glass fuses' code F is for fast blown the second number is the current, but I do not know what is the difference between L an AL (if there is any).

Could someone explain this.

• Please link to both data sheets. Commented Jan 19, 2020 at 12:58
• @Andyaka Unfortunately, I haven't any datasheet otherwise it would have been enough to read them to find the answer. Commented Jan 19, 2020 at 13:01
• Are you therefore suspecting that someone does have these data sheets then? Commented Jan 19, 2020 at 13:02
• @Andyaka It's enough to find someone that has experience with the fuse code letters. The labeling is pretty standard for the glass fuses. Commented Jan 19, 2020 at 13:05
• Who makes them then? Commented Jan 19, 2020 at 13:06

They are the same 5A 250V fast acting low breaking capacity fuses (just one omits the A of ampere)

The glass cartridge fuse code is structured in this way

|Acting Speed| |Current rating| |Breaking capacity| |Voltage rating|


or

|Package size code| |Acting Speed| |Current rating| |Breaking capacity| |Voltage rating|


Acting speed

The time it takes for the fuse to open when a fault current occurs. It code could be:

M - Medium Acting (Mitteltrage)

T - Slow Acting (Trage)

TT - Very Slow Acting (Trage Trage)

Fuse Breaking Capacity

It is the current that a fuse is able to interrupt without being destroyed or causing an electric arc with unacceptable duration. The capacity of a fuse to operate between the lowest and the Rated Breaking Current code could be:

H - High Breaking Capacity

L - Low Breaking Capacity

They are apparently a different size 3/16 vs 4/16 diameter and 3/4 vs l inch length.

I base this on having just bought 5 amp which didn't fit a 5al socket.

• If you have a new question, please ask it by clicking the Ask Question button. Include a link to this question if it helps provide context. - From Review Commented Jul 26, 2023 at 9:55
• @DanieleTampieri The expression "how do I know" is NOT asking a new question. It is an idiomtic way of saying "I know thi because ... " Commented Jul 26, 2023 at 13:36
• @DavideAndrea The expression "how do I know" is NOT asking a new question. It is an idiomtic way of saying "I know thi because ... " Commented Jul 26, 2023 at 13:37
• @Russell McMahon Yes, I understand that "how do I know" is NOT asking a new question.. That is unrelated to my evaluation that Harold's post does not answer OP's question. Commented Jul 26, 2023 at 14:44
• @RussellMcMahon, thank you for pointing it out. However Harold's post in nevertheless not an answer. Commented Jul 26, 2023 at 15:09