The problem really stems from the fact that the charger is female meaning the male dangerous part ends up on the battery. A 10A fuse is the fix, plus the sugru.
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Fuse on the board port side right? I’m looking do something about Sparks when connectting the charger.
Can someone inform on how to put a fuse to protect it? And maybe which fuse? Genuinely not sure, so an idiot guide style would be great, or a link
pic of the aftermath?
There really is not much to see… the pins in the connector are gone and there is a solidified brass puddle in the bottom of the connector… I really cannot believe it stopped arcing!!
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@Andy87’s experience made me start putting fuses on my charge port and this just doubles me down.
Everyone, can we please order these 7.5A 58V fuses and put them on your charge ports? I think every new build should have this. And those of us that have extra could toss a few in the free stuff thread.
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You told me that a while back Best thing ever, fuse are life saver ! Now I systematically fuse charge and discharge
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Man I’m glad nothing bad happened!
These pins aren’t suited for e-bikes or e-boards BTW. We put too much power through these!
Edit : Had to move out before finishing my post ; anyway its good you’re safe!
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About a month ago I made a mistake while creating a cable to connect the switch to the battery and and I switched polarities. I burned an ESC and I was luck that nothing else worse happened. The switch melted and that stopped the current flow.
I don’t know why I didn’t verify the connections and correct polarity, I always have been careful about this but not this time. Now I’m on the market for a new switch, ESC and battery since it was alrady in bad condition. For now I will push a regular longboard. 
Probably obvious but just in case… Put the fuse on the board side, not the charger. You want to break the circuit inside the board in case pins fuse shut on the board and all hell brakes loose. Really glad you’re ok @amazingdave!
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See. I wish it was still obvious, but I’m still learning all this, including what it means to break a circuit. Im guessing i attach it on one of the two wires inside the board coming from the charger, so that it “blows” when an issue arises so the battery circuit is no longer connected?
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Burned down house - great way to see in the new year
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It goes in line on the positive wire. Never hurts to do more research. Often hurts to not do enough research!
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I would fuse only the charge, not the discharge; see
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Why not the discharge ?
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I’m not electronic savy… but are you sure putting your charging port over the metal mounting plate has nothing to do with it? Shit looks like an arc conducting-tesla coil-hut burning-transformer circuit !!
Meh… If you are having the fuse blow then there is something already much worse happening. The times I’ve had fuses blow in my power systems, the BMS or ESC is already on fire and malfunctioning. The fuse only prevents a short through your system to reach the battery and make more things catch on fire (The fire on your ESC/BMS might still propagate to the battery but it’ll be much slower).
If you are at speed and a discharge fuse rated appropriately for the board blows. Your ESC should already be a piece of flaming toast and you should have already bailed, if not, may the force be with you…
Failure order should be ESC/Switch/Charger BMS Fuse Battery
This means that your BMS should be able to handle more current than your ESC. Your fuse should be able to handle more current than your BMS and your battery should handle more current than your fuse (maximum for an 18650 30Q cell is about 80A, I’ve tested this).
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Panel mounted ports in metal are not:
A. Dangerous B. New