Why not use the VESC battery cut off? It’s much safer than the hard cut off from the BMS anyway.
i’m having a huge duh moment here, forgive me. So brain sleepy lunch after. I think i was conflating the voltage cuttoff with the max amps and other related VESC settings. That’s totally worth experimenting with and i have just the board to try it out on.
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I agree that it’s not definitive, but at 10-12s single drive I do think we’re pushing the limits of VESC 4. Just trying to find ways to make it work😀
@longhairedboy go ahead hang on to it for another couple of days and experiment with the VESC settings. Testing is probably the hard/dangerous part, so be careful out there and dress for the fall.
The brakes cut off when when you brake hard over a long duration, or brake from fast speeds. And like you said they sometimes cut out intermittently and then come back… But when you’re going fast that intermittent cut out feels long enough to cause major problems to your physical well being lol.
How would the vesc fail? Torque motor spins about 67k rpm on 12s. Would it launch you off the board going full speed?
would set your wallet on fire
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Woo that’s a nightmare scenario. Why is that happening. At fast and slow speeds? Maybe ur hitting ur high voltsge cut off with the increased voltage coming back while braking. Spikes up to 10 volts I think. The regen options don’t shut things down I think.
Could anyone possibly help? I’m having issues with windows and connecting the right firmware. I bought a brand new vesc from Ollinboard what’s the firmware version with those vesc
If you just got it, it should come with 2.18 h/w revision 4.12
When I try to upload my firmware it starts with a different ip address, after I change that it then states buffer timed out
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QUESTION: TRAMPA MTB DUAL 6364 136 kv, 15 MOTOR/66 SLAVE PULLEY, DUAL OLLIN 4.12 VESCS, 180 LBS AND 225 LBS RIDERS, (ONE AT A TIME), MOSTLY FLAT RIDING 95% OF THE TIME. I WILL HAVE TO FIT BATTERIES INTO A SQUARE BOX IN THE MIDDLE. I AM LOOKING FOR BATTERY SUGGESTIONS BASED ON KV SIZE AND AVAILABLE SPACE.
Guys I need help. I will be running 8s 8000mah 15c lipos and a 12T/36T belt pulley set with a vesc. All thats left to run my board will be a suitable/proper kv rating motor that I am pondering over. Thinking of getting a 270kv 70-80A motor (need help distinguishing what’s the difference if it’s 40A compared to 70A cont amp motors), but would that be ideal for, say 30km/h? Also do sensored motors make much diff on a vesc as compared to a sensorless one?
Also, after doing some calculations, I’ve found out that my proposed set up with 270kv motors and on 8s max voltage (33.6v * 270kv * 7 = 63504 RPM) is above the 60,000 rpm limit. Is 3000 rpm above the limit consider safe or dangerous already? What would being over the limit damage?
The VESC runs at 95% max duty cycle so you should be safe at 60328. It should quickly drop from max voltage anyway.
So hooking up a 270kv motor on an 8s is fine? How did you come up with the 60328 rpm? Can you show me the calculation? Thanks @Jinra
It’s 95% of your max erpm. I think you’ll be fine on 8s, but it’s a bit too close for my comfort. I was thinking of doing 260kv on 8s myself.
Thanks for the valuable information. I am quite new to this so what are the dangers if I push past the 60000 rpm limit? Does my vesc fry or my motor overheats?
VESC can fry, namely the drv8302 chip
Alright will keep that in note. I have some other questions, say a particular motor has 270kv and draws continuous 40 amps, is it any different comparing to a 270kv with 80A continuous? Like in terms of performance and durability. That being said, my battery can draw a maximum of 120A. So would I be underperforming when I fit it with the 270kv 40A continuous as compared to the 80A continuous? Any other things to take note when using a 120A batt on either both of these motors?