Fuses that matter.

Rodman, I agree that something must have gone wrong. The residual gas in the fuse could have pressurized sufficiently to crack an existing flaw in the glass I suppose.

It would be nice for Mr S to return the fuse to Jerry, for analysis.

After reading so many posts about fuses on the net, it seems too many people are overlooking the safety factor these fuses are made, and used for. Some people even state they are using jumpers in place of fuses. Some people state they leave the home while their system is running too. I hope they don't live in a multiple family dwellings, and are putting others at risk by doing what they choose with these protection devices.

I've also read somewhere that Liquid Fuses may be filled by them. In my opinion, if the fuses were tested before by any independent labs such as UL, they need to be tested by them again, such as UL (other testing agencies too), for any of the past testing agencies markings to still be valid. The fuse element (or burn wire) runs hot. It may be close to its melting point during a listening session. If that element is immersed in a liquid, they may not blow as fast as originally designed. A fast blow may take on qualities like a slow-blow fuse. A slow-blow can be slower yet, than its designers originally intended. I can see the liquid heating up, while cooling the element up during operation. This is why I believe they need to be tested accurately again, in my opinion.

Maybe these were retested by some independent testing agency after the modification? The equipment they use to measure the blow times can be expensive, and may not be owned by some of these after market companies. It would be nice to know if they were tested, and provide a new spec sheet too. It's common sense that when the element (burn wire) is immersed into a liquid, specs will change.

A lot of engineering goes into products, and all of the parts used in them. For the customer to change to something that may have taken years to be designed by knowledgeable people, may be more risky that they realize. Don't forget, every part used took time to design. A fuse is there to protect the product, and to prevent fires. I would make sure the fuse you use can safely protect you, and your product. Neighbors too. I wouldn't experiment with unknowns. Again, designers put fuses in them for protection.

Also, you may void any warranty on your product. It's not a manufacturer's responsibility to repair something that may have been protected by a fuse that was changed by the buyer/user, if it wasn't an exact, specified, replacement. Just because somebody else is doing some experiment and nothing has happened yet, doesn't mean it won't sometime after. Use common sense. Some people seem to be going too far, without having any knowledge about the engineering that went into these products, and possibly, the safety risk.

Hifitime, You make some valid points, but I think we need to give people like Jerry at Audio Magic credit for not being complete idiots. I don't know if he has had his fuses retested by UL or not. But I do think when he was designing his fuses he probably didn't just drill a hole in a 5A fuse, fill it with some quaker state 10W30, and start selling them as 5A fuses without ensuring that they blow at the specified current.

However, his customers need to use some common sense too. When I replaced my standard 8A fast blow fuses with the AM liquid filled fuses I bought a 7A fuse instead of an 8. I'm hoping that gives me a little extra insurance that the fuse will blow when (hopefully before) I need it to blow.
I've had about 7 of these fuses in my system since they first came out. They do make a difference, and I think the risk is low enough to be acceptable. For those that think otherwise, there are plenty of non-fluid filled fuses out there. I also have a few SR fuses in my system.

This is all ridiculous. The fuse leaked and the fuse blew. One thing may relate to the other but not necessarily. There is not much engineering in fuses. The filament needs to be sufficiently thin to blow with at the rated current. If it is slow blow there needs to be some heat absorption to allow for surge currents. In some fuses the filament is designed to be exposed to air and in others not.

ULs is a for profit company and, of course, sells its services. Having retesting of fuses would cost money as would certification of an audio component. This is why you don't see these labels on much audio equipment. Designers can roughly calculate what their circuit should draw and try a fuse with just above that value. They then can see if it works. If they blow many fuses, they go to a higher value, unless they find a problem with their circuit. Obviously too high a fuse value may allow overheating of the equipment and the potential for a fire or a safety issue.