What’s the smallest fuse holder? looking for about 150A for my main wire.
Depends, how big is your fuse? Some people even just solder directly onto the fuse, no holders needed.
well i am looking for a fuse holder/ fuse combo. the fuse would match whatever style the fuse holder accepts.
Do you want to fuse your main power wires?
yes i think it’s a good idea to prevent a short. i should be able to set the limit to 150a in focbox to prevent a blown fuse i would think?
Exactly what you’re looking for doesn’t really exist. Nor is it necessary for most people. But you can look at Lacroix boards:
Or Enertion:
As an example to how some have implemented fuses in prebuilt boards. They both use a custom designed PCB with a fuse mount to securely hold the fuse in place. The slow blow fuses are spec’d for the application, 150A is wildly over rated if you actually want it to blow. You essentially need to find one of these or go this route in designing your own to implement. But understand if the fuse blows you’re very likely to subsequently blow the esc. So in truth I’m not sure what the fuse it protecting.
Also this is absolutely NOT what you should do:
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There are thousands of fuse holders on eBay and Amazon. I am just seeing which fuse holder is the smallest as there are more than 20 different types of fuses that could work. I am running dual 5k motors so in theory I could draw as much as 10kW from the battery, which is a lot more than 150A at 12s. So even with a 150A fuse I would be limiting the motors. The point of the fuse is to prevent a fire from a short circuit which is really the point of any fuse in any application. I am not sure why it would take out the ESC if the fuse blew. Most electronic devices wont sustain damage if they suddenly lose power. If they did, people would be frying all of their stuff in their house every time the power went out. So I’d say that is an engineering flaw in the device then if that happened.
I am curious how the FocBox is hooked up to a 70A fuse in your pic. I would think you’d be limiting the device heavily since I think it can support dual 80a draw on the motors? If I recall right anyway.
motor amps ≠ battery amps.
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Sure, but there is no getting around ohms law. If a motor can handle 4kw and that’s what you’re feeding it, then the battery will see more than 8kW draw, which at 12s would be about 190A. I never got a good answer of how to determine how much current draw from the battery a particular motor will draw. Like if I am running dual 63100s, how much current capacity do I need to power them?
Does anyone know if the FocBox Unity+ has an internal fuse? I guess if it does, then no need to add another fuse.
That’s not how electronics work, the motor will only use however much the ESC gives it, which you control with the VESC tool. And the battery only provides as much power as the ESC is requesting, barring bottlenecks.
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i doubt any esc has internal fuse, maybe some heavy automotive one do, but certainly not any small esc that we use in PEV
e: some esc has fuse on accessory port, but that’s it, not on the main line
Obviously that’s not the case if you’re here unsure of what to buy.
What is the source of this fire? Because if it’s a betting game the battery is way more of a fire hazard than the esc. If you’re concerned that the esc will short I would argue your battery should be powerful enough to burn right through that short and break it. Which is the outcome I have observed many times when an esc has a catastrophic burn.
Because you have no where for the esc to dump power, that its now generating as you slow and the motors spin, while you likely also panic hit the brakes when something goes wrong. It’s not a storage device.
Frankly, you are leagues away from being able to select and spec a fuse if you don’t understand that motors aren’t drawing power you’re feeding them via the esc.
I can’t explain this all to you. But I suggest dropping the idea to add a fuse. As both of those shown were spec’d for unities and somehow you think their wrong.
It does not, why would those companies in the above pictures I posted (one of which being the original producer of the unity) be using a fuse if that was the case. And unrelated don’t use this esc and support the massivewanker selling them.
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any capacity
depends on what you set your esc settings to
if your battery is your bottleneck, then you set your esc to that spec and that will in turn determine what your motors will draw
if it is not the bottle neck, then the limit will be set to whatever your motors are rated for
if both of these options surpass the rating of the ESC, then set the limits based on the specs of the ESC
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hmm I thought the focbox unity was a good ESC. one of the better out there. no?
well in my case I am running a battery with 360A capacity, so the bat is not the limiting factor. The ESC is the focbox which I think is rated for 80A motor, 160A batt or at least as far as I can find on their website. the motors are rated for 5kW, so I would view the ESC as the limiting factor. so I am trying to select a fuse based on that.
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The smallest fuse holder is to solder your wire to the fuse.
Don’t trust numbers coming from people who are trying to sell you stuff.
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Yes
Ah? U bring ur home powerwall with u?
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