CA v3 limiting power even when I raise the limits.

theotherkid

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I built a 60V 36A dirt bike for my son out of an old Razor MX500. I got the power throttle override working great, however I'm still getting limited on power according to my CA diag screen. The A and W both flag even if I raise the power limits up way above. The only factor I haven't addressed that I can think of is I'm using a much larger shunt than necessary because it came with my used CA and I didn't realize it would keep me from changing the Calibration setting from High (kW) to Low (W) because you can't set a 0.25mΩ shunt when it's set to Low (W).

Parts:
Motor - BM1109 style 48-72v 3000W BLDC motor
Controller - Generic 60V 36A controller (18 mosfets I think)
Battery 60V 20AH w/ 40A BMS
CA HC V3.0 (bought used with no sensors, just a shunt)

Speedometer, Temp, PAS, Torque, AUX POT, are all disabled. Basically just have the throttle wire plugged in to the CA and THrO out to the controller. Ground and +5 are still connected directly from throttle to controller (does that affect anything?)

Throttle mode set to Power. (same results when set to Current)
Max power set between 1500w and 3000W doesn't seem to make a difference beside making the throttle go full speed before a full twist.
Max amps set between 26A and 46A does same thing.

Still a little unsure about how these affect things. I can't finely tune them as good as advised because of my Calibration setting is stuck on High (kW)
A-Gain - 999
W-Gain - 550

I'm only pulling about 26A and up to 1.8kW max or take when looking at the screen. I thought maybe my THROTTLE OUT Up Rate was keeping it from using full power during acceleration, but that doesn't fix it and it still maxes out around there going uphill with heavy load on.


Other unique details:

The controller has a 3-speed switch that is hard wired to speed 3 right now (It has a loop plug hanging to do this when no switch is connected to stay on highest speed) and a seperate "speed limiter" wire that i hooked to a switch. It seems to work to drop the speed whilst keeping the throttle action the same.

I'm realizing as I type this up I need to retry changing the throttle to Pass-Thru and see if it still limits the speed. I think I tried that first before I started adjusting calibration on the CA, but I have done so many things one at a time i'm starting to forget if I tried that after i got the throttle calibrated correctly. Either way, the A and W are flagging when it's reaching max speed so it has to be something in the CA (unless i'm just a moron).



PXL_20231016_224530772.jpg
 
I built a 60V 36A dirt bike for my son out of an old Razor MX500. I got the power throttle override working great, however I'm still getting limited on power according to my CA diag screen. The A and W both flag even if I raise the power limits up way above. The only factor I haven't addressed that I can think of is I'm using a much larger shunt than necessary because it came with my used CA and I didn't realize it would keep me from changing the Calibration setting from High (kW) to Low (W) because you can't set a 0.25mΩ shunt when it's set to Low (W).

If the flags are still activating, then your system is somehow exceeding the limits even if it's a peak so short that it isn't captured in the data, or something is wrong with the CA settings themselves, or there is a bug in the firmware version your CA has (there are some; this seems the most likely problem based on your info).

Which FW does it have (version shown on startup screen during power-on)?

Do you have the serial programming cable? If so, you can update to the latest firmware, and see if it fixes it. If you already ahve the latest firmware, you can backup your settings to a file (and take pictures of every setup screen just in case), and do a full factory reset on the CA to see if this changes the issue, then reload your settings. That will eliminate the possibility of a corrupt setting (I recommend redoing your settings manually from the pictures rather than from the file, though).



Parts:
Motor - BM1109 style 48-72v 3000W BLDC motor
Controller - Generic 60V 36A controller (18 mosfets I think)
Battery 60V 20AH w/ 40A BMS
CA HC V3.0 (bought used with no sensors, just a shunt)

Since you're using such a small controller, you can install yourself a "CA connector" in the controller (I'll link a post or thread for that if you are interested in trying). Then you can use the low power range for finer control.


Also, do you know if the CA was working in the original owner's application? Or if they had problems and that was why they were selling it?



Regarding actual power usage: if the conditions you're riding under don't need more than a certain amount of power, that's all the system will draw. What conditions are they?

Speedometer, Temp, PAS, Torque, AUX POT, are all disabled. Basically just have the throttle wire plugged in to the CA and THrO out to the controller. Ground and +5 are still connected directly from throttle to controller (does that affect anything?)
I usually recommend running the throttle from the CA itself if you are sending it's signal there. No grounds between the CA and controller other than battery negative.


Still a little unsure about how these affect things. I can't finely tune them as good as advised because of my Calibration setting is stuck on High (kW)
A-Gain - 999
W-Gain - 550
These are part of a feedback loop to help smooth out changes in the readings / limiting. Is your problem worse with them lower, or higher?



I'm realizing as I type this up I need to retry changing the throttle to Pass-Thru and see if it still limits the speed. I think I tried that first before I started adjusting calibration on the CA, but I have done so many things one at a time i'm starting to forget if I tried that after i got the throttle calibrated correctly. Either way, the A and W are flagging when it's reaching max speed so it has to be something in the CA (unless i'm just a moron).

If the CA has no speed sensor, and has no S flag, then the CA is not limiting the speed.

It may limit your current or power, because it can monitor those via the shunt and the battery voltage reading, but it can't limit speed.

If you use Bypass mode, it will directly pass the actual throttle signal thru without scaling it.

IIRC, if you use PassThru mode, it still scales it but it doesn't limit it.

The *controller* could be limiting speed, as some have speed limits built in that you can't change (some of the ones that come with displays have speeed settings in them that can be user-altered, but even some of those can't be changed). If the controller has no display, then there is no altering it's settings, as very very few of the generics have any kind of programming software available outside the factory.
 
That was very informative, I will try and gather some of that information over the next few days if I can. First snow here tomorrow in Michigan so I'll be a little hindered getting it figured out. The firmware update/reset sounds the most promising. I'm pretty sure i was getting more power on high speed before the CA was installed. The person that sold it to me used claimed it worked fine. I didn't do a reset before setting it up, but I went through every screen available in the menu and made sure I had it all set. Messing with the gain didn't do much when i played with it, but I didn't test it a ton. I was worried I was going to goof something up. The A-Gain can't go any higher than it is already set at 999 and I didn't notice much change adding or subtracting 100 from the W-Gain.

As far as conditions go, I'm just trying to set it up so my young son can ride it with the speed limit circuit on (or a different CA profile if that turns out to work better in the end.) But I want it to be able to suck the juice if I turn the limiter off and carry us both up a hill if I'm riding him home quick (I can get on the back and ride him down the street to the neighbors house where he can ride with friends). It does okay right now, but I know it has more power than it's giving me right now because it had more before the CA was installed.
 
Once the issue is resolved, then for the limited vs unlimited versions, you can setup a preset that is power-on default that has all the limiting you want for him. Setup the second preset to unlimited, then open the CA and unplug the cable to the front panel buttons. Connect a reed switch or hall switch to the right-button wires, and put that switch somewhere you can access, preferably under a handlebar grip, etc. Then you can make a ring with a magnet in it, and wear that ring when you are going to ride this, so that your grip on the bars deactivates the limits. If you have to have him ride it *after* you've deactivated the limits, just turn it off and back on, and it will be limited again.



If it had more power prior to the CA installation, then choosing BYPASS mode in the CA feeds your throttle directly to the controller unmodified, and should result in exactly the same power you had before. If it does not, you have a different problem such as connection between controller and battery (like at the shunt).
 
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