In the glass fuses' code F is for fast blown the second number is the current, but I ignore what is the difference between L an AL (if there is any).

Could someone explain this.

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


|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:

FF - Very Fast Acting (Flink Flink)

F - Fast Acting (Flink)

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

|improve this answer|||||

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.