Actually according to Littelfuse’s Specs. For that particular fuse, it’s rated for a max of 32V
https://www.mouser.com/ds/2/240/Littelfuse_JCASE_Datasheet-523198.pdf
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Just use the smallest 40 amp fuse rated for ~60V and you are fine.
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Technically fuse is made to blow based on amps and not voltage. It’s more the current or even more accurate, the wattage that blows off the fuse. Off course those specification on 12v is meant for precise 12v 30A = 360 watt. Say you run 36v, it will blow when you do 10A draw as they are equivalent of 360 watt.
This is wrong. ^^^ Fuses blow at a current in x amount of time. It has nothing to do with the wattage going through it. They are essentially a resistor with a low melting point. So when a high current goes through, it generates heat (I^2*R) and the fuse melts, opening the circuit.
For example, the little fuses posted above,
A 20A fuse will blow in 10secs at ~45A or in 1sec at ~88A.
The voltage rating determines the ability of the fuse to suppress the internal arcing that occurs after a fuse link melts and an arc is produced. If a fuse is used with a voltage rating lower than the circuit voltage, arc suppression will be impaired and, under some overcurrent conditions, the fuse may not clear the overcurrent safely.
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Most fuses voltage is overrated however 36v car fuses should be fine up to 12s
@pxss just make sure people get that the big “S” stands for “seconds” here, not “series cells” 
I really hope you don’t give this as advice to people…
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well, this is personal experience, many people just make a rough guess about the fuse, this can lead to serious injuries at high speeds.
Those are two separate issues. Making a rough guess obviously isn’t good either but saying that not having a fuse all together is just spreading bad information.
A properly specced fuse won’t blow under any normal operating conditions but could potentially stop someone’s entire board from going up in flames, or worse, their entire house, particularly when battery fires are much harder to put out than most house fires or normal electrical fires.
true that, that is what a fuse is for.
but i see a lot of people taking “some” fuse - even asking about microfuses in some cases.
you should always know the short circuit current of your batteries, then you can search for a fuse.
not like, uuh my VESC has 50A * and my other one has 50A so this would be 100 but it is too big for me so i take 70A
i do not encourage people to not make their boards safer
I have the feeling people could have a look at what hag already been posted, explained, linked. I see people asking and explaining over and over again the same stuff
I’ll humor you, and take this scenario. Lets say joe has a 10S4P battery pack that can do 60A, driving dual ESCs. Yes, the ESCs are capable of 100A but the battery isn’t. So joe goes to radioshack and buys a fuse with a current rating of 60A. He then proceeds to forget to set his max current setting on the ESC to 30A each and instead puts it at 60 each.
While not having a fuse could have very damaging effects on his battery and overall build if said batteries were to go into thermal runaway. Having a fuse could save his build.
Based on the chart below…:
A 60A fuse can handle 80A for 1000secs and 100A for 80secs.So joe’s fuse blew and he now has a chance to review his settings and catch his mistake for a whole $5 instead of spending $500+ on a new battery and escs. That is, if his whole setup didn’t burn.
Using a fuse even an underrated (60A) one isn’t something that is going to make shit catch on fire. If a fuse goes, it means your battery was being damaged anyway as there are very few of us that have anything higher than 10S4P 30Q packs or Lipos capable of 60+A continuous.
100A fuses for most, if not all of us is plenty and there is no good reason to not use one other than laziness.
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I have the low profile ones, 60A 58V rating. Pretty compact.
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Just came across this whilst researching on the web. Very interesting.
Fuse ratings
Continuous rating
Fuse are marked with the current that they will continuously pass (at a standard temperature) without blowing, known as the continuous rating. It is good practice not to allow the continuous current to exceed 75% of the fuse’s rated value to accommodate momentary current surges that might cause the fuse to fatigue over time or blow unnecessarily (nuisance blow).
Blow rating
In simplified terms this is the current rating at which the fuse will blow. Most fuses have a blow rating around twice that of the marked continuous rating. So a 5A continuously rated fuse will have a blow rating of 10A.
Has anyone tried a fuse of this type?
I just have antispark xt90-s in my build I would like to protect my build more i have dual vesc and lipo in serie 10s 20c 5000mah
That’s not a fuse, it’s a circuit-breaker
the function is not the same ?
Yes they do the same thing and can be easily switch back on. But the form factor is too big to up in a board. It’s big and tall.
hmmm what do you recommend? maxi blade fuse is for 24v, and my 42v batteries is a problem?
https://m.littelfuse.com/products/fuses/automotive-passenger-car/high-current-fuses/bf1-58v.aspx
Try to use the proper voltage and current rating. You don’t want to go through the trouble of installing the fuse only to have it not function.
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