Are all fuses created equal?

Hi Nick,

While there are a number of differences between the specs for the two fuses, I don't see anything all that dramatic. Although the Conquer ADL datasheet is not nearly as comprehensive as the Buss MDL datasheet.

The Conquer ADL has a nominal melting spec of 48 amps squared-seconds. The corresponding figure for the Buss MDL fuse is 62.3, which would suggest that the ADL will blow a little bit more readily. However, those are nominal (typical) figures, and each fuse can be expected to have a fairly wide tolerance (range of variation) about those numbers. Also, the specific test conditions are not indicated in the case of the Conquer fuse.

Both datasheets provide figures for min and max blow times at 200% of rated current (which would be 4 amps in this case). Those numbers are 5 seconds min and 120 seconds max, for both fuses.

"Interrupting ratings" are 100 amps at 250 VAC in both cases. Cold state resistance is spec'd a little higher in the case of the Conquer ADL fuse, but the ADL datasheet doesn't indicate what current level that is measured at, so direct comparison is iffy. And that number doesn't have much if any relevance to protection anyway.

That covers essentially all of the relevant specs that are provided in the ADL datasheet. The Buss MDL datasheet is more comprehensive, as I said, so a fully conclusive comparison can't be drawn. And who knows how accurate the specs are? But based on the info that IS provided on the ADL fuse I don't see any worrisome differences.

Best regards,
-- Al

Liz, They forgot to mention Fuzz indeed in Wiki

Al, I guess that answers my question, there is little difference between fuses manufactured by reputable companies. At least as applies to the two brands in question.

I will rest easy knowing that damage done to my amp had nothing to do with the fuse selection. And, I will be far more cautious in terms of checking my tubes if a fuse ever blows again.

Thanks again.

@Marakentz the nice thing about Wiki is that if the information is missing or is not to your liking you can always add or change it. I look forward to learn about fuzzes!

Nick_sr,
Your thread here, plus a little down time for minor surgery, got me looking further into the whole fuse thing. Here is a link with some interesting reading posted by the Roger A. Modjeski, the designer of Music Reference amplifiers.
http://www.audiocircle.com/index.php?topic=105425.0
Another interesting post is located down near the bottom of the same page by Scott Novak, which starts out...

After having spent 6 years performing safety testing on switching power supplies I would be very concerned about using any protective device, fuse or circuit breaker, that did not have safety agency approvals.

Update, I got my amps back from service this week, it turns out that only the led for the bias adjustment was fried. So I guess the fuses served their purpose after all.

I would also like to take this opportunity to thank Quicksilver who graciously honoured the three year warranty which had elapsed about a month before the amp failed.