I’m looking into picking a fuse for my build. I run 12s lipos with dual TB 230kv motors (rated at 80amps) and dual TB 120a Esc’s. I’m thinking of looking into some 58V 80A fuses, does this sound alright, should it be higher/lower? What do you guys use on your builds and what would you recommend.
Tbh I don’t use a fuse and have never had a problem
That should be fine. Just make sure you use easily replaceable ones. You might want to look into getting a circuit breaker rated at your spec instead. You can easily reset it if you trip it.
At 12S though, I doubt you will reach the 80A. You might hit max, 60A going up a hill or something.
Well the goal is to not blow the fuse while riding and instead protect against shorts stuff.
I was more looking for links and stuff as there are ALOT of options and i’d like to go with wjat is proven
Let us know what you end up with maybe ill integrate in my packs in the future.
I was running exactly the same setup as you and with an inline watt/amp meter going uphill the peak amp draw on my battery was only 18.4a @ 12s 37.38a @ 6s
Awesome info, thank you. I wanted to put in a watteter but i decided against it. I know ive seen people post that they use fuses. Anyone?
A fuse is good insurance in case one of your esc’s shorts out or you get a short in your wiring. a fuse will save your batteries. You can get regular size ATC/ATO fuses in 40,50 and 60 amp on Amazon
most I see are rated for 36v, but I’ve also heard people using 60v systems on them.
What is true? I’m looking at fuses for my 50v lipo.
They should work ok for 12s or you can get a maxi fuse. There bigger and have heavier guage wire
I never found a proper fuse. I did alot of research though. Never underspec your fuse, if it says 36v do not use it on a 50v system. The voltage ratings are very important for dc systems because they define if the fuse will actually stop current from flowing if it gets blown. Dc voltage likes to arc much more than ac due to the fact it’s “constant”, which means fuses need to then have more arc suppressing material in them to counter that. If you do under spec your fuse what may happen is that the fuse blows at whatever current it is rated at and then an arc forms between the two fuse terminals, thus completing the circuit and nullifying a fuse in the first place.
You CAN use fuses that have ac only voltage ratings but you need to AT LEAST double what your are running. Example, if you run a 50v Dc system you’d need a 100v ac fuse at absolute minimum.
Tldr; dont underspec your fuse or it wont work as expected if and when it is blown.
Good point, I’m actually not using a fuse on my new setup but my bms has short protection
I use mini-ANL type fuses, they have very low resistance and a large contact patch. The onla problem is the relatively large holder (slightly larger than one 18650 cell). As a bonus, they are available up to 120A.
Only 18A going uphill ??, … some people here have reported taking up to 60 A going uphill ?
That is what the inline meter showed at 12s Going up a 10% hill. Don’t know how some are pulling 60a. Maybe on a 30-40% hill
@Namasaki could you help me find the regular size fuses? All I can find above 40a are the maxi fuses. Thank you!
Small blade fuses only go to 40a max. You need to use the fat blade fuses if you want to go larger. I have thought about getting something like this for a more robust, compact fuse
Thanks Jinra ok, so im not crazy, couldn’t find small blade fuses above 40 anywhere. I was looking at the ones you pointed out and the mini anl that flatspot mentioned. Let us know if you try it out.
I’m afraid @Jinra is correct, the 50a and 60a fuses that I saw on Amazon where miss identified as regular ATO/ATC fuses. When I checked closer the size is large like maxi fuses. https://www.amazon.com/Teal-60A-Standard-Blade-Fuse/dp/B00W8WHLE6/ref=sr_1_2?ie=UTF8&qid=1473822881&sr=8-2&keywords=60a+ATO+fuses
If your discharging through a good BMS then you could skip the fuse because BMS should have short protection. I’m actually not using a fuse.