I’m running 2 CFOC2 v0.9’s on my mtn board with two Keda 63-64 motors. They get up to about 50A each when I’m climbing steepish hills. I’m using those SPIM08HP LiIon cells from the electric bus program in 6S1P. I keep thinking of going to 8S, but would probably want to go to a different type of cell. These cells are good in a number of ways, but they’re quite bulky for their capacity.
On the two wheeler I’m running single CFOC2 v0.9 with a generic 63-74 motor, on those same cells in a 10S1P config. I don’t normally push that one as hard, but probably pull 50A on occasion.
Same here, i only got some feedback when i asked in the onewheel builders forum. And even then it was only from one guy(onewheel, 12s, phub motor). Seems that his focer only acts out (drv errors but no need to reboot) on hills when motor amps are set to >40A. If they are >70A he needs to reboot. This seems to be the exactly the same observation as on all my boards.
I wonder if switching mosfets could help reaching higher amps without drv errors or is it just less heat?
This issue seems to be particular but frequent enough to need to be addressed. I ran the CFOC2 0.9 at 13S at 60A+ on my ebike at one point without issues. MOSFET selection is a factor but the gate drive needs some more help in my opinion. I tried some stuff that didn’t work but I’ve some more tricks up my sleeve that just needs some experimentation to figure out.
Going to a 4-layer board could enable some stuff that helps too. The 4-layer board pricing on JLCPCB is pretty damn good now
On my mountainboard enabling hfi helped somewhat because most of the time the drv errors show up at high current / low rpm. I had some dangerous situations when accelerating full throttle and one of the motors cut out. Nowadays this happens less maybe bc i got more carefull and dont accelerate that hard.
The onewheel has hall sensors and there the problem is most obvious. Probably because it is in low rpm high current situations most of the time. I also switched the motor from wye to delta to get higher top speed and this only worsend the situation. Im thinking of switching back to wye config.
On the 2 longboards (one is 13s) i have the least troubles. I can still get the error when accelerating hard from a standstill.
Mine are quite conservative. I run 2 FOCers, one for each hoverboard 10" wheel. They are connected via CAN bus. Current is limited up to 20Amps for each wheel/focer. Battery is 10S2P, but I have now made new one for this summer 10S8P.
Did one think about a brake resistor channel, in case you do not use this controller with a battery but with a power supply which does not like power going back from the braking motor?
Hi, @shaman. Just a quick question before doing this.
Will this UART communication work with FOCer? I assume this is more or less built in original VESC, but I was wondering if this is going to work with FOCer.
I’ve implemented UART telemetry on both of my FOC’er boards. I’m using bluetooth to send the data to an LCD on my hand controller. As long as you have the protocol for the firmware version you’re using, all will be fine. It’s a bit frustrating that the protocol seems to change with each firmware version.
I’m having issues with my footpads. When I switch to the balance app, the state is stuck at calibrating. I read you have to run the detect calibration for the IMU. However, after running it, applying, and switching back to the balancing app it still says calibrating. Any suggestions?
Tested today a CheapFOCer2 0.9 on my GF’s board and had some issues when accelerating hard from standstill as @doomy describes, but without going into limp mode. Some DRV OC faults were reported. Went back to the configuration and made sure my ERPM limits were correct…and they weren’t (now using variESC to avoid setting them up every time). Also lowered motor amps to 50/-30 and battery to 60/-20 (10S LiPos, plenty to go around…but defaults are kinda insane). Everything works fine now, so I’m even giving HFI a go! Thanks a lot @shaman for your hard work.
@thunkar how did the eRPM limits improve hard acceleration from a standstill? I’m guessing sensorless operation? If so, are talking about the openloop eRPM settings? Does using any of the presets help?
I’ve found that selecting the 'large outrunner" option for motor detection, even for smaller outrunners, yields better results. Detection accuracy affects low-rpm performance. Then also playing with the switching freq can help too.
That is fine, I was just wondering if that is going to work. If you say that is OK, then yeap, thanks a lot!