you’re talking about the HCX-D223V1 right? if it’s charge maximum is 20a what did you have your battery min at?
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-20A per vesc so -40A total.
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awesome imma change my settings now lol
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yeah guys, just add: XXXTREME TECHNOLOGY. Simple really.
Brian I thought we already discussed this. Juggalos aren’t allowed to do math, so that kinda rules out all of EE and other hard sciences.
What you’re describing is essentially the function of a rheostat/dynamic brake. You probably don’t want to be handing out “don’t buy” recommendations when you don’t have experience with the device in hand though.
Their function is to prevent exactly what happened to OP.
Rather than try to build in two separate discharge/balance systems, a BMS with a higher bleed discharge spec would likely suffice.
Really we just need to set our expectations of what to expect from a $30-50 simple BMS. And as others said, not all BMS handle over voltage this way
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“if used correctly” is the catch. If the seller can’t even describe in detail what the specs are than how are you supposed to be able to design a system that uses it?
So hence the “I wouldn’t buy this” recommendation. You could make one yourself, anyway. It’s not a complicated thing. At least then you’d know what the specs are.
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Well no such device could work on an unspecified battery voltage, for starters.
A 9S battery would need a much different cutoff voltage than a 10S battery. And neither one would need a 57V or 53V cutoff.
There’s so much ambiguity I would never use that.
Make one your self from a zener diode, a power resistor, and a piece of aluminum.
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I fear you might not grasp this topic firmly enough to make such statements.
Care to explain why cutouts can happen when braking at full battery?
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I’d love to hear you explain how you think it works. 
damn you didn’t know about that yesterday hahahaha
Glad you’re ok man. Get yourself a 223. I have basic knowledge so tend to sway towards the most expensive and highest rated units I can. I read ages ago about @eBoosted having issues with discharge bms’s so went with the bestech. I was lucky enough to get an unfulfilled special order version rated at 120amps. I have never had that issue even though I live at the top of a steep hill and always run full charge straight down the bitch.
Then again I rarely brake.
Ignore this drivel.
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I had this issue so many times until I decided I care less to overcharge the battery for a short time than loosing brakes on a downhill or right before a bus crossing.
I’m making all my boards with bms only for charging keeping an eye on possible pgroups drifting
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Ever used the 223 Alan? Mines been stellar. Its only gone into protection mode once during charging because of a bad solder joint on the charger leads but discharge wise its been spot on.
Maytech will make you whatever spec you want if you order 2. Thats how I got mine when the other guy pulled out. Pricey though for 120amp. 160 bucks aus
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yeah its here --> https://www.electric-skateboard.builders/t/closing-tonight-01-16-19-maytech-r2-style-remote-sample-tester-buy-including-mtvesc6-6-dyno-brake-and-motors/80239
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For me being confident foot breaking at speed beats the crap out of any electronics solution. I’m foot is ALWAYS there 
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I have one of these but haven’t used it since I was informed it is not capable of 12S.
The BMS units I use (SuPower) have no issues braking at full power on 10s, but braking on my 12S board, I have gotten the no brakes run off before. However, I believe that this is not due to the BMS, rather the VESC. The VESC high voltage cutoff is 57V if you look in the tool. I think the idea behind this RBrake was based around the VESC voltage. So you get diminishing results the lower the voltage.
I could be wrong but I thought they were simply trying to prevent the VESC from hitting 57V, which in my case causes my FOCBOX’s to restart, losing all braking power. On 12S since the starting voltage at full charge is 50.4, it is much closer to that risky number. Observing ESC monitor from my bluetooth module, I can confirm that on braking it will exceed 57 when at totally full charge.
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I spoke to Agnes from Maytech recently and she said that they now have the rheostatic brake for 12s…
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Has anybody tried these on a build? I feel like for braking redundancy this looks like an interesting idea. Maybe with front wheel drive.
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I think @Grozniy once posted a pic of them but not sure he has/use them
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It would be ideal if some innovative esk8 genius designed an intergrated wheel pulley/diskbrake for a mechanical backup.
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