Fardriver ND72260 Inconsistent Throttle from 0 RPM

[ManicMods]

Firstly, Happy Friday! I've just joined your community, and looking forward to contributing. Riiiight after this plea for help PROMISE!

I picked up the Fardriver ND72260, kitted with a Kunray motor, and new in box. I have a throttle issue that I think relates to the controller, which I will build upon below...

Configuration:
Controller: Fardriver ND72260
Motor: Kunray 3000W with thermistor
Battery: UPP 72V 20AH (100-3000W) 60 Amp
Throttles: x3 (Kitted, Bafang, TBEST <- Represents just about any generic throttle you'll find on Amazon)

Issue: When throttle is applied at 0 RPMS, 1 out of every 3-5 times results in a regulated very low (~10%) throttle. When assembling the reference video, I also noticed the MTPA appears to be circled red when having issue.

Testing:
-Worth mentioning, not my 1st electric DIY and I tend to be meticulous about wiring and connections.
-Tried three different throttles defined above
-Auto learn program ran multiple times successfully but not resolving issue (
-Three Speed parameters all brought to 100% temporarily
-Ratios in Speed all brought to 100% temporarily
-Park and Brakes disabled
-TCS Disabled and enabled to test all with eventual and identical issue
-All wiring reviewed, connections re-seated
-Observed the MTPA changes from a green check to a bike circled in red when having issue

Unfortunately, I do not have a spare controller of this capacity so I am going a bit crazy until I receive a replacement mid-next month. Kunray's support has been pretty awful, and I am waiting for Fardriver to deliver me firmware to attempt a reflash. Going to drop reference videos below my signature. If you have any feedback, tips, or requests I'm all ears!

Jeff


Video showing issue while on jackstand:

Teaser short of my project vision:

 

[amberwolf]

Not sure what you mean by "throttle controller"? Do you mean the actual throttle itself? (the mechanical device with a hall sensor or pot, etc., that generates an analog output voltage of some range)

 

[ManicMods]

Not sure what you mean by "throttle controller"? Do you mean the actual throttle itself? (the mechanical device with a hall sensor or pot, etc., that generates an analog output voltage of some range)

Yes, the throttle itself. I've always referred to it as a throttle controller since I think of throttle as the signal. I've updated post accordingly as it's more clear. Thank you.

 

[amberwolf]

Ok. just making sure; sometimes when people use different terminology than is common, it can lead to confusion, either because they actually mean something a little different, or the assumptions of what they're trying to say are different.


Something to keep in mind with FOC controllers is most of them use the throttle to modulate torque (phase current), so no-load testing doesn't usually produce the same results as actually riding does. (for instance, a tiny amount of throttle gives full speed output of the motor).


The pulsing sound of the system when the problem may indicate the controller is pulsing the entire phase output on and off repeatedly, which usually means either:

--there is a timing problem with how it's sending the phase currents so it causes current spikes that exceed some limit (built in or user-settable) so it shuts down the output, current drops below safe limit so it resumes, and repeats this cycle.

--there's something wrong with the motor itself, such as a winding fault (damaged insulation allowing occasional high-voltage short between either winding and stator or two phases, etc) that causes the overcurrent response.


Timing issues can be incorrect autotune detection of parameters, so that it's not modulating the phase currents correctly, or it can be a position sensor fault, either something wrong with the sensor(s), or more likely induced phase current noise into the sensor signal or supply lines (or both), causing spurious signals triggering incorrect controller phase current drive.

 

[ManicMods]

I follow, thank you! The mini-ATV feels great on my road and little trail, but same problem occurs. 1 of every ~3 throttles from 0RPM and I'll only receive 10% throttle (crawling.) I have to bring it down to 0 again, and repeat until I have normal throttle. That's why I spent most of my time trying different throttles, and mappings shown in vid.

Not sure I hear the pulsing sound, the only abnormal sound I've heard is an air-like hissing when motor stops sometimes. You can't hear it in video.

I'm going to test a little bit more tomorrow and report back. I'm still getting familiar with app, and it's complex enough I may be overlooking something critical (Like that MTPA outlined.) It should have been programmed out of the box, but I'm still not convinced something has failed in controller or motor like you suggested.

Appreciate ya

 

[amberwolf]

Unless the pulsing is an artifact of YT (unlikely given it isn't audible except when the problem happens), then it's probably a symptom.

I wonder if anyone else can hear it: it seems very clear to me...maybe I'm imagining it?

 

[ManicMods]

Got it, good ear. My rear sprocket is a hair off center, and it's creating intermittent drag. I think that's what you're hearing at least. When I adjusted chain, I could turn motor from axle by hand thru the entire rotation. I expect it to loosen up and quiet down after third ride.

 

[amberwolf]

If the noise might be outside the motor/controller system, I'd recommend disconnecting the drivetrain from the motor to ensure it has nothing to do with the problem, just in case.


FWIW, something intermittent like this is "never" an actual throttle problem (unless you see the actual throttle voltage misbehaving as measured by the controller itself in any display it provides, or as measured by you during the events vs normal).

It's almost certainly going to be something between motor and controller, either in the setup of the motor with it (because autotune isn't perfect) or in behavior of the controller software in response to motor response to controller current drive of phases, or position sensor issues. (which are almost always going to happen during highest instantaneous phase currents, as those create the most induced noise in other phases, sensor signal/etc lines, and sensors, for inside the motor, and within any high current / battery voltage and/or ground busses inside the controller itself, and all the wiring between them.

If it works correctly (other than this issue) under load, it's pretty likely the motor tuning is correct.

But the controller software (firmware) could have bugs in it that cause or allow this condition to happen given the right input conditions.

Sometimes the position sensor problems cause the controller to think the motor is running too fast, so it slows it down, but since it wasn't really fast, it's now way too slow.

The other potential issue is a battery brownout where there is just enough instantaneous voltage sag (which won't show up on a typical voltmeter, but should on an oscilloscope setup to catch it and hold it on screen). to trigger the controllers low voltage protection, not it's shutdown LVC, but whatever it's got for battery protection that lets it still keep working but at a lower power level.

 

[ManicMods]

Thanks Amberwolf. I took the chain off yesterday night, which eliminates noise. I ran calibration in that configuration, but the throttle issue continues. It's so odd it only happens from 0 RPMs. If, I rev and it has normal acceleration, the throttle will not be limited in any range. Bring it back to 0 RPMS, and I have a 1 in 3 chance of experiencing the limitation.

I received a H90TCS选项.bin file from FarDriver to update firmware. I specified app, but I believe they sent me file for PC application which I cannot use. At least, I do not see it when filtering on filter or interlace files in the Comm tab. I'm waiting for more information from FarDriver.

I don't have an oscilloscope to test voltage at that level to determine sag. I feel I'd experience issue more consistently if it was this, however. At this stage, I'm simply going to wait for FarDriver firmware info, as I also wait for new controller. I receive the new controller next week, and a replacement motor in the beginning of March. While I cannot isolate at this stage, at least that will isolate it to controller or motor. And since this is a largely undocumented issue, I will be sure to follow up on the matter with results. Once I have determined what failed, perhaps I can even send it to someone knowledgeable for further troubleshooting.

Will keep the thread updated, and appreciate it!

 

[ManicMods]

With so many tests performed, and intent to share the final project, I took the time to compile the pre-completion carnage. I hope this is not viewed as self-promotion as the content is to create exposure and ultimately point to the solution for others. Nobody should have to go to this length for a kitted solution like this.

In the >8m production below I detail how awesome but restricted this build is. All signs point back to Kunray or Fardriver. Either Fardriver has a big problem with these lesser-used controllers, or Kunray's programming is creating problems I can not overcome with learning or Settings. There may also be a incompatibility with these motors and controllers. (2 complete kits tried in video, with 2 different power sources.) There are SO many settings in the Fardriver app (not a complaint) that I feel like there also could be an obvious miss somewhere. I show my settings at 2:30. My second kit observed same problems out of box, and on bench, so if it WERE a setting, I am not sure why it's being set. Each change was not taken lightly; I researched and only adjusted what I was able to research and relate to the problem.

@amberwolf - I wanted to give you a direct shout out in video, but I always collect approval 1st and it was a late-thought. I really appreciate you taking time out of your day to come to table. And, you have a great ear! Because you were RIGHT about the noise you heard, it happens with the chain off despite my earlier judgement. You can hear it without the chain at 0:45.

You all will probably appreciate and relate to the journey within. I always try to tell a story, and entertain. Let me know what you think! (I'll be pointing Kunray and Fardriver to it as well )

Looking forward to any input you may have. Questions about any part of this build or problem are welcome

 

[DingusMcGee]

Manic mods,

Not all BLDC motors will work properly with just any Fardriver PID parameters or those assigned by default to your controller.

The fardriver manual lists 13 groups of PID parameters see pg41. The usual default set group 4 is called Heady Duty Motor.

QS motors work excellent with groups 2, 3, 4. The Lightening Rod Big Block works quite well to high midrange rpm using group 6 but does not work at all well with the “high performance PID’s” , 2, 3, 4 & 5.

In the PID group is a parameter AN (values 1 to 16) 1 is for a hub motor and 16 is for a mid drive motor. Numbers 2 - 15 may lessen chattering?

You can sometimes get rid of motor hesitations, chatters, shutters etc by getting a PID parameters group suited to your motor config.

 

[ManicMods]

Manic mods,

Not all BLDC motors will work properly with just any Fardriver PID parameters or those assigned by default to your controller.

The fardriver manual lists 13 groups of PID parameters see pg41. The usual default set group 4 is called Heady Duty Motor.

QS motors work excellent with groups 2, 3, 4. The Lightening Rod Big Block works quite well to high midrange rpm using group 6 but does not work at all well with the “high performance PID’s” , 2, 3, 4 & 5.

In the PID group is a parameter AN (values 1 to 16) 1 is for a hub motor and 16 is for a mid drive motor. Numbers 2 - 15 may lessen chattering?

You can sometimes get rid of motor hesitations, chatters, shutters etc by getting a PID parameters group suited to your motor config.

Appreciate this, can you point me to the manual you are referencing? I've been reviewing their 6 page manual on programming, and only see 9 PID groups. Group 4 points to Medium power motor. Kunray's programming actually matches that group with the exception of MaxKI. MaxKI is set to 16 while manual's Group 4 says 12 per table below. On a related note, my AN is set to 10 which I believe is off. I was thinking of adjusting to 16 since it's IPM motor, but I had a savvy user suggest it should actually be 0.

	StartKI	MidKi	MaxKI	StartKP	MidKP	MaxKP
4	4	8	12 Kunray=16	40	80	120	Medium power default

Added your notes to my case, and will be reporting back later today hopefully.

 

[ManicMods]

The throttle hang is resolved. This was the bonus throttle issue I received with second controller, not to be confused w/ larger throttle issue that plagues both. Since only the second experienced this, I compared their settings. Toggling one setting resolves this and results were repeatable.

Just didn't want anyone scratching their head on that one. You can DM me for more info, but I will not publicly disclose at this juncture. I may even interrogate you

 

[amberwolf]

The best thing you can do to help others is to post the solutions, in text, not just videos on an external site, to whatever problems you have, as well as sufficient description of the problem they fix, for others to find and use whenever they have such problems.

Requiring people to message you in private for the solutions only works as long as you're still around here and still willing to tell people what they are, and still remember the details.

 

[ManicMods]

The best thing you can do to help others is to post the solutions, in text, not just videos on an external site, to whatever problems you have, as well as sufficient description of the problem they fix, for others to find and use whenever they have such problems.

Requiring people to message you in private for the solutions only works as long as you're still around here and still willing to tell people what they are, and still remember the details.

I could not agree more, friend- nothing worse than coming across a deadend thread. This response is only temporary as I step thru creating exposure of the issue and button up notes. While I clearly asked for help, a large part of that video was creating exposure to what seems to be a known issue without resolution. Within the video, I isolate it to Kunray's kitting. I received overwhelming feedback that further suggests their programming is to blame. Nobody should have to go to the length I did to isolate an issue. And nobody IMO should be buying any FD kits from Kunray until the issue is resolved.

I've shared the video with Kunray to move towards warranty action. I cannot return the kit, so I am demanding they replace it with their Squarewave (Non FD) controller kit which also uses the MY1020 w/o a thermistor. I plan to continue the PSA as the response unfolds. I love solving problems- I won't solve Kunray's programming issue but I will do everything I can to ensure community is aware of the problem. Companies that leave the QA to us outrage me. To make it even more personal, they've taken their old (Well-reviewed) product page and updated it for this problematic kit. So the volume of unsuspecting and misled buyers will only increase. I hope that makes sense, and appreciate ya!

 

[amberwolf]

Realistically, it's unlikely anything is going to change any of these sellers' or manufacturers' ways. They do things however they feel like it, and even the best of them don't usually change anything based on buyer feedback.

They just don't care--they already got money from the buyers, so that's all they care about. Most buyers won't bother trying to get it back, and most sellers are outside any legal jurisdiction of the buyers to do it anyway, depending on payment method.

If you do manage to get them to change, we'll all be pleasantly surprised, but I wouldn't expect it.


For some examples, take a look at the shitty software (both for setup and the firmware inside the controllers) and support that some decent controller hardwares have, making them nearly (or actually) unusable for quite a few buyers. They're not really all that cheap, either. Plenty of threads and posts about them (votol, sabvoton, fardriver, kelly, mobipus, etc); and posts about the attempts to get the manufacturers to do better, and the responses that show they literally don't care and refuse to change anything for the better (some of them deliberately make things worse and harder to use).

Doesn't make sense, but that's how they work.


So, anything we can do to help each other fix these problems and deal with them is good.

Anything we do to make it harder for each other to do that is not good.

 

[DingusMcGee]

ManicMods,

The manual:

http://www.siaecosys.com/upfile/202108/2021083051492073.pdf

The PID parameter table:





PID parameter settings 4, 5 & 6 cannot be changed with the Fardriver App. They are the controller’s ROM to this App.

Settings 1, 2 & 3 are the parameters of the integration control used during start-up, mid-range and the near abouts of max input, respectively.

So, if you have problems at start up, try changing the start parameter going from 2 thru 16 until the problem is diminished/cleared up upon a start-up test for each parameter change.

 

[ManicMods]

Y'all are legends , thank you so much. Looking forward to providing update later this week.

 

[ManicMods]

A day late, a dollar short. I've worked thru any and all sensible recommendations from communities, and while it was greatly appreciated, it was to no avail. In meantime, Kunray has ignored all correspondence thru Amazon and email. Amazon was able to force the return, and I have opted for a different kit all together.

I may not be a fardriver tuner, but have isolated the main 'limited throttle issue' to the Fardriver controller or Kunray's programming of it. Both kits used legitimate Fardriver controllers, and given the overwhelming positivity around quality, I'm confident in them and that Kunray is ruining the experience. This is especially true given the secondary throttle issue:

The secondary throttle issue (throttle hang) was caused by the Function Setting "Follow." It was disabled on my first controller, and enabled on the second which experienced the throttle hang. There were a wealth of other programming deviations between the two Kunray kits. No quality control at all. That's it- I hope this documented experience helps others. Drop me a line if you had a question, and thank you all again!

 

[Username: Required]

I had the same issue and I think I fixed it by changing LM from 22 to 13 after reading through the Kunray and Fardriver documentation online. AN switches to 10 after autolearn so I keep it there. I am also new to this so sorry if you try it and it breaks your controller.

Good luck!

 

[Paris88]

I have this exact problem and have been looking for solution for weeks and no luck. I couldn’t ride on uphill as though the throttle isn’t responding at all even on full-throttle. I was going crazy and never knew I wasn’t the only person. Please report back when you have a solution and will appreciate.

 

[HumboldtRc]

I figured out the issue! There are settings under “Product” that seam to effect the throttle response! What an odd spot for put those very important settings. I was getting a delay on the throttle response. On the app I could see it only getting to 90-100 throttle (0-256 range) while under 500rpm, and once past that it would go full throttle output to 256 on the graph. So I just started messing with any and every setting there was. FwReRatio and Re Acc seam to effect how fast the throttle responds from 0rpm.
Hope this helps someone! I was going crazy trying to figure out why this 72260 FarDriver controller was not working well. Try messing with settings under the Product tab.