Yes, you want to use a DC (not AC only!) rated breaker (or fuse) that is *at least* as high a voltage as the maximum voltage of the circuit it must break. Otherwise, it may arc across the opened circuit and cause a fire at that point, as well as not breaking the circuit so whatever caused it to blow in the first plac eis still getting power.
SunPoweredWorldTour said:
where do I look for the one you talk about. and what amp do you think I should use.
Lots of different kinds. I'm using Bussmann ones on my trike, but that's just because I already had them. Littelfuse makes them too, as do other places. Bolt-on or Bolt-down fuses can be found via google searches from many places; I'd recommend first going to the manufacturer you want to use and using their tables to determine which one to use first.
The ones I'm using are in pictures here
https://endless-sphere.com/forums/download/file.php?id=210467
https://endless-sphere.com/forums/viewtopic.php?f=2&t=67833&p=1263618&hilit=breaker%2A#p1263618
For rating, as I said before, it depends on what you want the fuse to do for you, as to what you want to rate it for.
What specifically do you want it to protect? Wiring? Battery? Controller? ??
originally I design this solar eBike to run in Asia where I knew I might spend days without seeing a person
so I double many thing.
Then you might be better off with the breakers Rassy suggests, so that you can simply reset them instead of having to change fuses--if you ran out of fuses you'd have to directly connect things to bypass, and then have no protection; if there was a good reason for the fuse to blow, it could then damage the equipment.
But it depends on what you're protecting, and against what, whether a breaker or a fuse is a better idea.
I'm using ones that look like this:
https://endless-sphere.com/forums/download/file.php?id=210435
from the linked post above.