Fluke 77 III, 11amp fuse

[Oznog]

I have a Fluke 77 III and in a hurry forgot to move the leads off the 10 amp current input while working on a car battery. OK, fuse go poof! These things happen.

I went to Fry's, they want $19 for that fuse! It's not a regular size. Digikey carried them but they want something ridiculous too.

Does any surplus or discount place have these? I didn't pay all that much more for the meter in the first place! Guess I should buy a couple...

 

[Nigel Goodwin]

I have a Fluke 77 III and in a hurry forgot to move the leads off the 10 amp current input while working on a car battery. OK, fuse go poof! These things happen.

I went to Fry's, they want $19 for that fuse! It's not a regular size. Digikey carried them but they want something ridiculous too.

Does any surplus or discount place have these? I didn't pay all that much more for the meter in the first place! Guess I should buy a couple...

As you've found, these fuses are EXTREMELY expensive, and quite rare - they have a very specific use, and only very small sales potential. They also (presumably?) have to be far more accurate, and faster acting, than normal fuses.

 

[eblc1388]

Think of it this way. The cost is for the mistake you have made, namely passing high current through the meter. Without the fuse, the meter would be damaged or the leads insulation would melt and start a fire.

The fuse need to interrupt 10A or more DC current and could have several hundred volts across itself (worst case scenerio when circuit continuity is broken) is a hard task for a small size fuse. DC fuse is different to AC fuses.

The 10A range on my Fluke 75 is marked "unfused". Whether it is a blessing or shortcoming I am yet to find out.

But I agree to Nigel that the rare demand of the fuse would be the main cause for the high price.

 

[zevon8]

These guys maybe able to help.

https://www.tequipment.net/FlukeFuses.html

The prices seem not too bad. Not sure about shipping tho, it may cancel out the savings.

Atleast they do bulk quantities.

 

[Dean Huster]

Absolutely DO NOT substitute anything for that fuse, using only the original amperage, voltage and type specified by Fluke. That fuse is one of the things that gives the 77 it's Catagory II or III or IV rating and keeps the meter from exploding in your face in case you do something really stupid with it in a high-energy circuit such as 680v 3-phase stuff. You'll notice that this monster fuse is usually in series with a much smaller (and less-expensive) fuse. I'm very surprised that it was the "big" fuse that blew since it usually only goes when you screw up in high-voltage circuits that would cause the small fuse to flash over.

Contact a Fluke Service Center, probably listed in your instruction manual. Sometimes, electrical supply houses (the ones that deal with house wiring and industrial electrical stuff) will carry the fuses.


Dean

 

[jamesmi]

These guys maybe able to help.

https://www.tequipment.net/FlukeFuses.html

The prices seem not too bad. Not sure about shipping tho, it may cancel out the savings.

Atleast they do bulk quantities.

I have a Fluke 189 and also needed a fuse for it. After reading this post I ordered 5 440ma and 5 11A to take advantage of the bulk pricing. I received all fuses today. They are Buss fuses as indicated and come in Fluke packaging. I just thought I would let people know just even after the $12.74 shipping cost the total bill came to 57.74 which is still under $6 per fuse. Still a great deal compared to the price digikey wants.

James