Playback Design with Hifi tuning fuse

Magfan,

Yes, it was. I assumed (maybe incorrectly) that the same principle would apply to both circuit breakers and fuses where quality is an issue. In the article, the author goes on to refer to them as fuses so I assumed (again) that they operate on the same principle. One is replaced, the other reset.

Memory MAY be THE issue as a cheaper fuse conceivably couldn't withstand the repeated thermal stress as it nears its rating. I'm just throwing this out there.

There has been enough discussion, here, to support the use of better made fuses over cheaper ones. What the OP may be experiencing is his unit running close to its thermal limits too often. Or a fuse rating too low. A call to the maker would be in order to see if others are experiencing the same problem.

All the best,
Nonoise

I'd be curious to know what the UL test / qualification procedure are for fuses....
OR any other governing body, for that matter.

In a not-quite related phenom. Aluminum has no fatigue limit, so every mechanical stress cycle eats into ultimate lifetime.

Steel and its alloys have a fatigue limit which if not exceeded promises an essentially limitless liftime. Exceeding the fatigue limit begins stressing the structure and once you go over the tensile limit, you're all in.

Perhaps something similar with fuses, only electrical where the heat of passing current effect ultimate lifespan.

Seems a simple enough task for a manufacturer.

A quick test would no doubt ascertain current performance but do they test for the heat generated over a life cycle or is it mathematically arrived at?

It boggles my mind that a fast blow fuse goes in about 1/10th of a second and some slow blow fuses can go on for as long as tens of seconds. They're sacrificial in nature, so how does one guarantee consistency and do they dig deep enough into the specs when selecting them? Or for that matter, are the specs for heat generated wear taken for granted or even considered?

Huikenny, as I've experimented, it would be better buying some AMR fuses instead.

Best wishes,
Alex Peychev

one MAJOR key is process control during manufacture
Measurement instruments....like for metal thickness, are checked on a regular basis, calibrated regularly and have a gauge R+R study done annually.

ISO standards require the above, so buying from an ISO certified builder is IMO, a Key Requirement.

Once you have a database, turn the math guys loose on it, you can build successful models of most anything. We used modeling extensively in semiconductor manufacture.

I expect fuses to have very regular materials....the right alloy, internal process control and a well-trained workforce working to the build specification.

Go to the littlefuse site and read around for further info. I saw a white-paper there about fuse ratings /

As for a test: It of course makes a huge difference. The test cycle could be anything from stuff like.....10 seconds on @80% fuse rating / 10 seconds off for 1 hour, followed by 'test to destruction'.
The other test cycles I'll leave up to your imagination. I just made that one up.