It stops at 50,0V, not 50,4V if it’s what you meant.
Mmmm I wish it was rated to just a bit higher haha
If you have the A-model then it should have 2 trim pots available letting you change the floating/end voltage and constant current.
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Yeah that’s what I have and I trim it. I just want a readout of amps so that I can adjust it for fast charging when I’m out on bar hopping Skates ahaha
Overdischarge itself won’t cause any fire. But rather when you charge it back up. I think if a p group fails or a p group goes below certain voltage then it should signal the VESC and the vesc should react in the same way it reacts when the battery gets low.
I currently have diebiems on one board and it hate it when it shuts down momentarily when I go max throttle. Of course this started happening after the the battery had grown old, but this totally can throw you off the board.
BMS shutting down abruptly is very very dangerous. It should signal the VESC and it should slow you down gracefully.
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I believe most discharge related fires are either thermal runaways or possibly if you have one bad S-cell with weaker capacity or just badly balanced pack. Then the bad cell will get reverse polarized (cell voltage goes into negative) and if you’re still pushing any sort of discharge current I would imagine that the bad cell could experience a catastrophic failure. There might a be a punch-through in the internal separator and the cell short-circuits internally and then you will have resistive heating in the cell based on the discharge current.
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I’d still rather my board go up in flames than cut power and have me with broken bones. If bypassing means I can stop in an emergency then I’m okay with it.
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Jesus christ…
I’m looking at my living room (more like workroom) and just thinking of removing one table and building the pick-n-place machine in it’s place… Need to build the solder paste stencil jig… Reflow oven is usable already… Then just the production tester…
EDIT: I’m thinking of buying a Liteplacer open source pnp machine. The guy who sells the kits, lives about 20 minutes away, so support isn’t too far away.
https://www.liteplacer.com/introduction-f-a-q/
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Needs a couple more iterations, but it’s a good proof of concept for the testing jig for the charger and battery pad connections.
I’ll edit this post to add the later iterations once I finish it.
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Do you use spring loaded pins for the connection ?
I’d interested to see how you managed to make it. 
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I was originally planning on wrapping a couple layers of copper tape on the contact surface and then soldering wires onto the tape, but looks like I have none on hand at the moment, so I just twisted some multi-strand hook-up cable around the clamps. Should give a pretty good contact even on a slightly un-even surface. I’ll test it today.
EDIT: Works well. No problems with the contact resistance even at 10 Amps.
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Is there any way of including a fuse on the charge input (instead of using a inline fuse) looks as tho there might be space but proberly is not.
You can simply put a fuse on your charge wire. Here’s what I have:
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I suppose the 5 mOhm current measuring shunt will burn/blow away if there is a large spike, cutting the battery pack’s negative terminal.
Seems more like a fault than a feature ( i know thats not the intention of the shunt though).
@Darkie02, why not use a cleaner external solution? Something like @janpom pointed out above, or if space is not an issue, a personal favorite of mine-
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That’s what I do use but why not integrate it in to the bms? Why are we still adding a cable between another component? Is the only argument because we always have done it that way? Or is there a legitimate reason some one would not want a fuse on the charge when use it this bms?
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Because it’s easier to replace when it does blow. I’m for keeping it separate/modular so that pieces can be swapped out
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I’m using pogo pins from SparkFun to build the “bed-of-nails” production tester jig.
https://www.sparkfun.com/products/9174 https://www.sparkfun.com/products/9174
Also I got some feedback from the tester group about the charger and battery connection solder pad sizes and their clearance to the mounting holes, so I made a minor HW revision of 0.5-1 with these things corrected, I anyways needed to do another PCB order to get the solder paste stencil for the board, so I can order the new PCBs in the same lot.
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So what changed for it to be now viable alteration?
Testers brought up the clearance between the mounting holes (bolt heads) and solder pads. I decided to enlarge the mounting hole pad sizes and increase the area around them a little bit and needed to move the solder pads at that point anyway, so I updated their location and sizes at the same time.
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