To be honest, I dont like the idea of a BMS cutting power to my ESCs but I would like an indication if there is something wrong.
The unity supposedly takes care of low voltage cutoff, not sure about high voltage but im sure it would, but that would only work on a pack average.
The advantage of a discharge BMS is that it works per p group, so I would know if something was wrong with a particular p group without losing power to the motors
If you wire up the bms as charge only it will still take care of overvoltage in time of charging. You don’t want a bms to cut you out due to over voltage while driving anyway. That’s usually when you start riding with fully charged battery and break hard. Better overcharged the cells for some seconds than losing breaks…as min that’s my attention to it. Once you hit acceleration the cell voltage will drop anyway again.
Not sure if that’s possible, but you might be able to set up a undervoltage Alarm notification via app on your phone. This way you get a notification on your phone if one group goes down but the bms will not cut out.
whats this board for? that’a a ridiculous amount of power. what sort of wheels and gearing you using?
i have my board set up in this way. Unity is in bypass but all my lights are powered through the bms. This way if there is a problem with a single cell group then the lights turn off but im not thrown off the board
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yes unity for on/off switch. i have fallen before due to bms cut out. it happens right at the moment you put the power down and generally are committed to the acceleration. struggled to trust the board after this so never again will i ride a board that can cut from bms.
Haven’t had any massive issues with it yet performs fine lots of settings to mess around with.
The 2 issues I have come across are a little annoying tho. First off one temp sensor was broken displaying - 30 which didn’t allow the battery to charge (there’s overrides to disable the temp protection and I’m sure it’s a 5 cent replacement sensor but sucks either way).
But the bigger issue is I can’t get the precharge ciruict to properly work, no issues turning off the discharge mosfet’s but when trying to turn it on again the Vesc begin to flash but never properly boot up and the bms gives an error saying the precharge failed. Theres a precharge current adjustment in the settings but no luck fucking around with that.
So basically you can’t turn it off and on via Bluetooth without a loopkey which is annoying for myself as I prefer to run charge port only boards
But it by far has the widest range of settings in the app and a 200mAh balance current which is nice.
As far as BMS and cut outs go I’ve never had any overspecced discharge BMS’s I’d say 99% of issues with bms are because they aren’t designed for our applications and the factory settings are to conservative or incorrect.
When you’re able to adjust pretty much all the bms settings to whatever your liking you can gear your battery to be as agressive as you like.
Edit: added some app pictures. There seems to be a cleaner English translated app that came out recently haven’t been able to find it yet however.
App is called MaYi bms
Yeah I used to have the continuous 100A version on my 30q 12s6p. I stupidly had it on discharge too and it would cut off all the time from over current.
Lol im in the same boat, if anyone wants the 200a version I would be happy to sell it, got a 20a 50.4v charger that I would happily sell to and put the proceeds towards a balance charger
Maybe someone wants to trade… longest shot
BN 184mm hanger and a pair of his precision clamps + mounts would be sweet long shot
but open to propositions