Demystifying Accessory Fuses

Revisiting fuses. I currently have 2A mini blade automotive (ie 12-24V) fuse and holder on the 58V accessory circuit. There's not much going through it. After the buck convertors the total draw is about 20W or so. Slightly more accounting for convertor losses.
Fuse is there for the dead short scenario, intent is a bit more than the draw, but nowhere near the wire rating.

But, fuses are a bit of a mystery. Are Amps just Amps (in context) and have I got it close to right? Is there a right way to size commonly available fuses for 60V? I am not finding what I need on the www probably because I am not asking the right questions so will someone with some technical knowledge help demystify fuses?

TDB said:

Revisiting fuses. I currently have 2A mini blade automotive (ie 12-24V) fuse and holder on the 58V accessory circuit. There's not much going through it. After the buck convertors the total draw is about 20W or so. Slightly more accounting for convertor losses.
Fuse is there for the dead short scenario, intent is a bit more than the draw, but nowhere near the wire rating.

But, fuses are a bit of a mystery. Are Amps just Amps (in context) and have I got it close to right? Is there a right way to size commonly available fuses for 60V? I am not finding what I need on the www probably because I am not asking the right questions so will someone with some technical knowledge help demystify fuses?

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Fuses are HIGHLY unpredictable. 2A fuse will pop at 30a instant, hold 10a for a few seconds, 5A for a few seconds/minutes, maybe 3a it will do continuous. From the video: a fuse rated at 45s at a given amperage might hold it for 12minutes and more. Some manufacturers don't even include in their datasheet anything that is not a 5 or 10x overcurrent, too unpredictable.

Pair the intense heat and long time it takes to pop them with the sealed rubber house these 2a aliexpress fuses come with. The consensus based on experiences is with a moderate overcurrent situation the rubber house will smoke and melt together before the fuse pops.

I still use them, I'm just aware not to expect wonders.

So whatever works then?

I have same fuse holder and fuses. The only thing I need is for the fuse to blow before it throws the 30A(?) protection circuit in the BMS. That is a dead short scenario. I did that once without a fuse in a la-la moment. It seems to work okay with the fuse. As long as the fuse holder itself isn't the cause of a melt down... but I'll have a look at alternatives.

There are 12-24, 32 volt and 58 volt blade fuses available. All the holders look the same but they are NOT compatible with each other (except the 58 volt is supposed to fit in the 32 volt holders). OptiFuse are the only ones I know of that make the 58 Volt fuses.

https://www.optifuse.com/blog/p091102.php

Also note that the 'stranded wire' used by OptiFuse is so stiff that it can be substituted for concrete rebar.

58V. That's useful. Previously I was searching 60V and getting PCB fuses.

I found some 58V mini style fuses by PEC.