Hello, I am learning how to use the ASI bac855 on my Zooz bike. Using it with the 750w rear hub motor, 48v battery, pas, throttle and eggrider display. I have access to bacdoor. Currently I was able to successfully ran the auto time for the motor in both the sensor and sensor less tab. Also tuned my throttle. I can get it to run but upon acceleration from a stop, it shudders for a few seconds and once it gets going, it runs great. If I life the wheel off the ground and hit the throttle, it would take a second or two delay then slowly start spinning then ramps up hard. What settings can I look at to fix this?
Bac855 delayed start and shuddering upon start
- Thread starter vwrado
- Start date
PaulD
1 kW
Is the ASI set to sensorless? I assume your motor has hall sensors, correct? Did you successfully map the hall sensors?
I dont believe its set to sensorless. I was able to run the motor discover mode and input all the Hall Sectors with just -1 being the first and -1 being the last. So I believe that part is setup correctly?
Attachments
Check that the halls are working first, and if they are, rerun the learning function.
TommyCat’s phase wiring and hall sensor testing:
Testing BLDC motor's Phase Wiring - Hall Sensors and Wiring. - Electricbike.com Ebike Forum
Testing electrical components of a typical hub motor with a digital multi meter. First take a few minuets and look over the wiring going into the motor for cuts, scrapes, missing insulation and other wiring issues or poor connections that should be resolved first. Smell for...
electricbike.com
PaulD
1 kW
Both hall sector 1 and 2 are set to 4. None of them (between 1 and 6) should be the same number. That means the auto hall discovery didn't work properly. Here is a screenshot of the manual procedure:
I have done another auto discovery and this time it went smoothly. Runs better but still shudders from a dead stop. There is a big delay from when I hit the throttle until the bike moves. After it starts moving, it will shoot right up. Bike runs well if I start it using pedal or if I push the bike to start. For some reason it seems to lack power when its at a dead stop. Also, this is on sport mode and my pas settings max (at 5). If I lower the pas settings which cut the power, the shudder is much more apparent and requires me to pedal to start it up.
Are there any battery settings or protection that is preventing it to start?
I didn't get to completely test the halls manually but since I got many sucessful auto discover, does that mean my halls should be in working order?
Attached are the pics of my current settings in BacDoor for the motor and throttle
Are there any battery settings or protection that is preventing it to start?
I didn't get to completely test the halls manually but since I got many sucessful auto discover, does that mean my halls should be in working order?
Attached are the pics of my current settings in BacDoor for the motor and throttle
Attachments
Hey, what kind of geared motor do you have; does it have dual reductions or is it a MAC ( high pole count )
Also, what voltage are you running and how fast is the bike designed to go?
In either case it's the experience of grin technologies and many of it's customers that these ASI controllers can't handle the electrical RPM of a geared hub motor with a huge pole count ( MAC ) or dual reductions at very high speed.
On a MAC that trouble begins around 30mph on a 26" wheel... that's where it starts to exceed the eRPM limit of standard ebike controllers.
And apparently the tuning ability is not enough on these kinds of motors, the best you can get is stuttery at low speed, or stuttery at high speed.
Also, what voltage are you running and how fast is the bike designed to go?
In either case it's the experience of grin technologies and many of it's customers that these ASI controllers can't handle the electrical RPM of a geared hub motor with a huge pole count ( MAC ) or dual reductions at very high speed.
On a MAC that trouble begins around 30mph on a 26" wheel... that's where it starts to exceed the eRPM limit of standard ebike controllers.
And apparently the tuning ability is not enough on these kinds of motors, the best you can get is stuttery at low speed, or stuttery at high speed.
PaulD
1 kW
If you post your XML file, I can have a look at it. There are many parameters that can causing this. I've setup many high RPM motors with ASI without issue.
Also, I have had instances where the auto discovery of the hall sensors is incorrect - even if they look valid.
Also, I have had instances where the auto discovery of the hall sensors is incorrect - even if they look valid.
Hi PaulD, Here is my xml file. As of now, it still shudders from a stop and if I hold the bike off the ground, it takes a second or two until the motor ramps up. I have done the discovery mode several times and all seems normal.
PaulD
1 kW
One way to test to see if your hall sensor are the issue is to turn off (set to 0) the "fault tolerant hall" bit in the motor features parameter. If it doesn't work at all, then you know for sure it's the hall sensors.
This is a throttle only ebike, right? I noticed that your "control command source" is set to 4 (throttle or pedal sensor), I doubt this is an issue, but best to change it to "1".
This is a throttle only ebike, right? I noticed that your "control command source" is set to 4 (throttle or pedal sensor), I doubt this is an issue, but best to change it to "1".
slaphappygamer
10 kW
I’m using a BaseRunner and had a similar issue. I understand that the BaseRunner is made by ASI Technologies.
I also had shuttering when accelerating from a stop. After much digging, I found out that my PLL parameters were not correct. Once I adjusted those numbers, the shuttering stopped. I can now take off smoothly. Here is a link to ASI support page explaining more.
support.acceleratedsystems.com
I also had shuttering when accelerating from a stop. After much digging, I found out that my PLL parameters were not correct. Once I adjusted those numbers, the shuttering stopped. I can now take off smoothly. Here is a link to ASI support page explaining more.
PLL Regulation Control Loop - Technical Documentation
support.acceleratedsystems.com
Good news is that I have resolved my hall issue and now I can confirm that the hall sensor is working, redid the motor discovery and all is good now. Throttle when the wheel is off the ground is smoother now where as before, there would be a delay in throttle. The problem was I had my hall ABC wires incorrect.
However when sitting on the bike it seems that if I give it too much throttle off the get go, it would shudder but if I throttle slowly, it would go smoothly. Looks like I will try slaphappygamers advice next.
However when sitting on the bike it seems that if I give it too much throttle off the get go, it would shudder but if I throttle slowly, it would go smoothly. Looks like I will try slaphappygamers advice next.
slaphappygamer
10 kW
I highly recommend taking a picture of your settings before you start changing things. I took numerous photos as I progressed to achieve smooth acceleration under load. The photos have timestamps stamps and I can refer to my settings on a particular day and time. It took me a couple of weeks, but I had to squeeze time in here and there.
You also might want to check into the current regulator bandwidth settings. I couldn’t find the page on the ASI site. Good thing I saved the page.
You also might want to check into the current regulator bandwidth settings. I couldn’t find the page on the ASI site. Good thing I saved the page.
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Thanks for the attachment!I highly recommend taking a picture of your settings before you start changing things. I took numerous photos as I progressed to achieve smooth acceleration under load. The photos have timestamps stamps and I can refer to my settings on a particular day and time. It took me a couple of weeks, but I had to squeeze time in here and there.
You also might want to check into the current regulator bandwidth settings. I couldn’t find the page on the ASI site. Good thing I saved the page.
Just curious if I am reading this right, on the link from post 22, they said that the bandwidth is set up to 500 while on the attachment it said up to 5000. Which should it be?
