I run dual maytech V4.12 with FW 3.26 and trampa 136kv motors, there are some strange things happening.
First of all i think there's a problem with hall sensors in FW 3.26.
With FW 2.18 i could detect a proper hall sensor table.
With FW 3.26 the first and last hall table (0 and 7) has a value of 255 no matter which phase wire combination, with both V4.12 and motors i get the same results.
After setup with motor wizard there was no error message but later i did manual motor detection and when i tried to write motor configuration this appeared:
Hmmm... i can't post image here but the error message is:
"The following parameters were truncated because they were set outside of their allowed limits"
"Hall Table (0) -1 / Hall Table (7) -1"
When i ride it there's definitely a difference compared to sensorless mode but the hall sensors are not working properly.
there is cogging when starting in offroad conditions, slightly uphill only cogging, no start up is possible.
On flat concrete nice start up with slight cogging.
Furthermore i've experienced following problems (hybrid mode with traction control over CAN bus):
when i put a bit throttle one motor spins a lot faster than the other, with more throttle they spin equal, i've also tried without traction control and in sensored mode, always the same result. Only in sensorless mode they always spin equal.
Also one motor gets just warm while the other gets very very hot.
Also i can't use ackmaniacs android app anymore
For UART the baudrate is set to 9600 and the cables are fine, the app worked with FW 2.54 on my old dual V4.12.
With FW 3.26 the android app connects to bluetooth module but all displays show zero.
I tried both vescs with bluetooth module connected but with no results.
I'll switch back to FW 2.18 or 2.54 to see if the problems fade away.
This is apparently at the firmware. I have hw 6 and also trampa motors but with 118kv. Hall sensores (0) 255 (7) 255 but no error message. And the spinnig of the motors over canbus is the same at my Setup.when i change the Master Vesc and the ppm the other Motor Spin no Sync. My motors are not to hot and i can drive without Problems.
Is their any Problem If at the Hall table the first and last parameter is 255?
The table has 8 entries. In BLDC mode, the table should have the numbers 1-6 and two -1 entries. With the most popular hall sensor configurations, the two "empty" entries in the table end up at the 0 and 7 positions (first and last). (you wrote 255, I say -1. Same thing. )
Hi Roger,
Ahh ok!! Thx for the answer.
little update of my never ending test rides, i have tried FW 2.54 and FW 2.18 in comparison to FW 3.26 on my HW 4.12 (each FW tested for about 20 km).
I always had exactly the same settings on both HW:
My experience with FW 2.54:
I have to mention that i had a couple of ABS OVER CURRENT faults with FW 3.26 and FW2.18, too but only on the bench, not on my rides.
There is one strange thing with my motors, every 3-4 turns there is a short scratchy noise including a high frequent noise and i can feel a resistance when this noise comes up. But i doubt it's a mechanical issue because sometimes it's twice in one turn, then 5 turns nothing and sometimes never, sometimes only one motor. But always on both motors after riding , i recognized it after my very first ride and it hasn't change since then. Any idea what that could be @frank?
I'll let you know any news.......
hey @frank, yes i use 2 metal mesh filters each motor like you advise, i'm super careful with this jewels
.
I tried now a different sensored motor on one smesc 4.12. The motor has exactly the same cogging and what is weird, the motor has exactly the same behaviour as i described in my last post. Every 3-4 turns a strange noise and resistance. when i turn the smesc 4.12 off it's gone!!! To get sure it's not a problem with my cables i've soldered new short phase wires and sensor extension. Same cogging with short cables so i'm sure my smescs 4.12 are bad to the bone. Unfortunately i have 4 useless HW 4.12 now and also can't finish my urban carver build.
Now i gonna solder all cables, capacitors and connectors on my new esk8.de PCB's 4.12 and cross my fingers. I think it gonna be a night ride later and hopefully with a fat grin in my face.........
Sounds good but my money is gone, but for sure I need a change as soon as possible! Within the last 12 months I bought 6 HW4.12, 7 motors, 2 longboards, 1 urban carver and one holypro MTB. That's why I can't afford a car anymore :) I'm an esk8 addict, need to stop buying things, lol.... is there a therapy?
Joking aside, I have some updates. I switched to esk8.de controller 4.12 but the cogging and jittering is the same like before. But compared to the smescs 4.12 the strange noises are gone. Also I've tried another sensored motor (guess which.... maytech) and this motor is cogging, too. So I don't think the trampa motor is the problem (or all of my motors are broke, very unlikely....I would have another sensored APS motor to try....). Furthermore I've tried all 6 possible phase wire combinations, cogging is always there.
Take a look at my problem (plus test ride):
https://www.youtube.com/watch?v=RFA9374i2pk
No more ideas.........
The hall sensor implementation in BLDC mode is not working properly, and I haven't been working on the BLDC implementation for a long time. The trampa motors have low enough kv to work with FOC on hw 4.12, so you can give FOC a try.
Regarding dual motors, it is normal that they spin at different speeds with no load with the new firmware. The reason is that I have changed from using voltage control for the second motor to using torque control, because when a setup has dual motors with different KV or gearing one motor will take all the load when using voltage control. Torque control shares the load better and is smoother when transitioning from rolling to driving.
I will eventually have another look at the BLDC hall sensor implementation, but it is not easy to make it general since hall sensors almost never are mounter with neutral timing and all of them are different. The FOC hall sensor implementation works in a completely different way than the BLDC one and is unaffected by at which offset the sensors are mounted.
Hi All.. Just been added Thanks @Frank and @benjamin.
I have just got my vesc 6's amd will be installing them tomorow. I also have 2 Matech Vesc and am using them on my board with the 136kv motors. Seem like i am wasting my time with the Vescs currently and hope that the 6's will solve all my issues.
Cheers All
Mark
Thanks for explanation @benjamin i'll give FOC a try. But strange that one motor (the slave) got very hot and the other just warm, but I think this is a fault of maytech. More and more I like the idea of your trademark, a vesc should be a vesc, not a crap from anywhere. I think I gonna fry my maytech V4.12 first (before i try it with my esk8.de 4.12) because they are not really made for FOC but they perform bad anyway, nothing to loose. But my cables (phase and sensor) are 80 cm, I think this is too long for FOC, or?
Hall sensors are used on BLDC motors since the time that CPUs were way too slow to do FOC or too dumb to do sensorless. Back in those days you had combinatorial chips that would drive 6 FETs based on a PWM signal and the hall sensors. So even if the timing is off by a bit, I would expect motors to be able to run in "dumb" sensored mode. That said, if you can compensate for the timing, you can probably make it run slightly better. But we already do that by switching to sensorless above a certain RPM where BEMF measurements give nice commutation.
It's FOCing amazing @benjamin @frank!!! I changed to FOC sensored mode on my esk8.de HW 4.12's with FW 3.26. Start up is butter smooth and I can start from standstill anywhere no matter which terrain, even uphill. Just to mention, the maytech 4.12's were not performing well in FOC. Every time hitting the brake there were cut offs and DRV faults on both smescs 4.12, rubbish! I am so happy to be a FOCer now!
https://www.youtube.com/watch?v=ptlHqK7kqCA
Looks like it is working nicely now. FOC is what I have spent the most effort on with the recent development, BLDC is essentially the same as in FW2.18. There are a few improvements with HW6 for BLDC, but only to take advantage of three phase shunts. I will try to fix the hall sensor implementation for BLDC eventually though.