I think this is the special sauce that does that, and unity FW has no equivalent code right now in the same place. It looks reasonably contained and could be ported over.
It’s a long time ago I know, but just thought I would say it anyway.
I have just been in contact with support and was told that I can ONLY swap the XT-60 without ruining the warranty. Changing bullet connectors, wires, etc. will void it.
I don’t even know anymore what can be done or not…
I’m not often moved to write a post like this but… I’ve just wired up the unity on my build (upgrade from dual focbox/canbus). Turned on, connected, installed new firmware, ran guided setup and applied settings.
Everything worked perfectly, no glitches, no messing around swapping phase wires etc
Just worked.
I like that 
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Well that’s interesting, I was told directly by Enertion support that not only does it do cell balancing but will do it on both charge and discharge. Is this a new thing? Or was that guy just full of sh*t?
Can anyone recommend a good discharge BMS to pair with the Unity? Looking to draw around 150A peak on a dual-motor rig, probably 60A ish continuous
At 150A, I wouldn’t bother with a discharge BMS, for what reason do you want it? For me it just adds a scary failure point.
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+1 a bms for high discharge is like putting a extra unneeded fuse on your board
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Yep. It’s like putting at least 2 more fuses on the board if the BMS contains a fuse! So many extra points of failure.
Well mostly to prevent a potential fire if a cell becomes unbalanced on discharge… I guess the risk is small but not one I like the sound of. But I’m no expert if you have a good rationale as to why it’s a bad idea I’m keen to learn more? Sure it’s a “point of failure” but how often do these things actually fail? I never had a problem with my Evolve stock one until I wired the battery to it wrong and blew it up…
can confirm, had bms cut out whilst i was accelerating full throttle. stacked it very quickly due to being leaned so far forward. bypassed bms for discharge from that point on.
Problem is its so difficult to test without knowing your going to hurt yourself.
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I’ve got this if you really want it
Heyo @CarlCollins, any possible sale coming up soon? Just checking before a couple friends and i make an order 
Unbalanced cells on discharge is extremely rare. Unbalanced to the point of causing a problem is even rarer. Causing a fire? Almost unheard of. Fires are caused during charge or by short circuits.
Discharge BMS are useful where there is a good chance that the parts of the circuit that could pull current when the battery is already discharged. I would trust a VESC to not do that. For instance, in a 10s setup: If you have the VESC cutout under 32V, the chance of a cell being under 3.1V is very very unlikely. My 10s5p pack has no balancing and after ~100 cycles is still within 2mV, and I think it was worse than that to begin with.
Of course this calculation might change if you are using a bunch of recycled cells with unknown origin with all different capacities etc. Then again, I wouldn’t use that kind of pack in an eSkate.
For me it’s a risk analysis. What are the relative likelyhoods and risks of things happening and what is the consequence.
- VESC/FOCBOX fail open - low - loss of brakes, possible injury
- VESC fail short - very low - wheel/s lock, likely injury
- BMS fail open - low - loss of brakes, possibly injury
- Battery unbalance causing fire during discharge - extremely low - board is on fire - loss of brakes
you get the idea. If you don’t use a BMS and/or fuse, you can get rid of a few failure modes.
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I see, thanks so much for the detailed explanation! And that will save me a lot of $ on the BMS too. Got any recommendations on a charge only BMS?
Plenty of opportunities coming up, I would like to see a sale for World Schizophrenia Day or would we?
I know @brenternet is holding out for Towel day
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I shit you not, I was holding a towel when I read this
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Is it the darkness…or ya did unspeakable things with that towel?
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I was doing neck exercises to improve torsion in my upper vertebrae. Not having sex with a cotton hoop.
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