Grin BaseRunner v6 + GMAC10 + Superharness not responding to ERider t9 PAS

[emcdermid]

Hi all,

I am in the process of adding e-assist to my daughter’s tadpole trike, using some components for Grin. In this case it isn’t a full preconfigured kit, but rather a combination of some pieces I bought a few years ago and then was unable to immediately use, and a few new ones.

Specifically:

• BaseRunner V6 L10 controller
• GMAC10 hub motor
• Superharness
• APT 750C Display (Grin version)
• Grin bidirectional twist throttle
• ERider T9 BB torque sensor
• 48V battery

I’ve set all this up using the PhaseRunner software suite, loading the appropriate defaults for the controller, motor, and PAS from Grin (and saving them afterwards). Everything seems to work fine using the throttle - a backward twist causes the motor to push the trike forward, a forward twist applies regenerative braking.

The main problem is that the system seems to be ignoring the ERider sensor. No matter how high I set the assist level on the display, there is no discernible push from the motor.

Attaching to the controller via the PhaseRunner suite and observing the dashboard, I am able to verify that the PAS1 circle lights up green. With the trike on the ground, if I hold it steady and push on the pedal, I can get the measured voltage from the torque sensor up to about 2V before the wheel slips. In theory, the voltage range for the sensor is 1.5V-3.5V, so that seems reasonable.

I cannot, however, get the “average pedal torque” value to even chart at all. I’m not sure if that’s an indicator of a problem, or if I just don’t understand how that is measured.

A couple of other notes (which may or may not be related):

• If I chart motor current at the same time, I can see that it usually sits at a small amount (around .06 amps). When I apply torque to the pedals, the motor current drops to zero.
• Checking the “Virtual Electronic Freewheeling” option also seems to have no effect on the trike. It’s no easier to pedal on with that enabled than it is with the entire system shut off).

I should note that I do have a V6 Phaserunner as well, and have swapped it into the configuration only to get the exact same results. So I doubt it is the controller.

I’m mystified and befuddled - the sensor seems to be scaling the voltage and the PAS setup tab indicates the torque sensor gain is the correct 70nm/V, and the controller Is seeing that value. So I would think that should translate to power from the motor, but it isn’t.

I do not currently have the trike frame grounded to the battery ground. I know that some ERider setups have an issue if that isn’t the case, so am planning on ordering a cable to take care of that - but given that I am seeing the voltage change, I’m not sure that’s the actual issue.

My best guess is that I’ve got a setting somewhere that is effectively negating that torque input, but if I do I can’t spot what it would be. Here are screenshots of the various tabs to show the settings, even if I think they are probably irrelevant - maybe someone else can spot the issue, or at least compare it to a similar setup of their own?













Links to the components described:

• Controller: https://ebikes.ca/product-info/grin-products/baserunner.html
• Motor: https://ebikes.ca/shop/electric-bicycle-parts/motors/gmac10t.html
• Superharness: https://ebikes.ca/product-info/grin-products/superharness.html
• Display: https://ebikes.ca/shop/electric-bic...displays/750c-central-display-and-switch.html
• Bidirectional throttle: https://ebikes.ca/shop/electric-bic...twist-throttle-with-higo3-connector-plug.html
• PAS torque sensor: https://ebikes.ca/shop/special-lists/discontinued/erider68-4b.html

Any suggestions would be appreciated - I'm stumped.

 

[amberwolf]

The main problem is that the system seems to be ignoring the ERider sensor. No matter how high I set the assist level on the display, there is no discernible push from the motor.

Since the BR/PR is reading the sensor voltage, then it's obviously connected to the right spot, and all the hardware is doing what it should.

I cannot, however, get the “average pedal torque” value to even chart at all. I’m not sure if that’s an indicator of a problem, or if I just don’t understand how that is measured.

Since you're using the superharness and display, is that all setup to tell the BR/PR that it should be using the PAS / TS to do things? I have not used an SH based system, only CA based, so I don't know how the SH interacts with the BR/PR settings-wise. The CA is independent and all control sensors route directly to it and then it provides a simple throttle signal to the BR/PR, as the CA can't actually communicate with the BR/PR. But the CA has to be independently setup and configured, in addition to setting up the BR/PR--I don't know if the SH does.

If the SH does communicate with the BR/PR then perhaps it has control over what the BR/PR does with the PAS, the same way that a typical display-based controller system with PAS levels does--the PAS is all configured in the display (which would be the SH/LCD combo here) and then it sends that configuration control information to the controller (the BR/PR here) to tell it which assist level, if any, to use.

In a typcal DBC system it doesn't do anything at all until you change it from PAS mode zero up to some other level, as a safety feature so that just getting on or off the bike doesn't trigger the assist because of bumping hte pedals or throttle or something. If this system works similarly, what happens if you change modes from the display?

If I chart motor current at the same time, I can see that it usually sits at a small amount (around .06 amps). When I apply torque to the pedals, the motor current drops to zero.

If the powered wheel is offground, does that small motor current cause it to begin to spin?

• Checking the “Virtual Electronic Freewheeling” option also seems to have no effect on the trike. It’s no easier to pedal on with that enabled than it is with the entire system shut off).

That sounds like the small motor current is probably just this function, but that it is perhaps not set high enough to negate the drag of the motor itself (or perhaps the bike is just hard to pedal for some mechanical reason?).

 

[emcdermid]

Since the BR/PR is reading the sensor voltage, then it's obviously connected to the right spot, and all the hardware is doing what it should.

Thanks for the confirmation on that - that's what I thought too.

Since you're using the superharness and display, is that all setup to tell the BR/PR that it should be using the PAS / TS to do things? I have not used an SH based system, only CA based, so I don't know how the SH interacts with the BR/PR settings-wise.

As near as I can tell, yes. With the SH system, the PAS connects directly to the controller, not the harness. I do have the display set to match the 9-level settings, and assuming I change it up or down while I'm graphing the value on the dashboard, the controller does seem to be recognizing the change in assist level.

In a typcal DBC system it doesn't do anything at all until you change it from PAS mode zero up to some other level, as a safety feature so that just getting on or off the bike doesn't trigger the assist because of bumping hte pedals or throttle or something. If this system works similarly, what happens if you change modes from the display?

I'm afraid you lost me with the "DBC" acronym, so I'm not sure if I'm following your question correctly.

I have tried bumping the assist level up, including to the maximum "9" setting, with absolutely no discernible difference. It's as if everything is working and being read properly except for that final step of actually causing the motor to turn.

If it wasn't for the fact the throttle works, I'd suspect the motor. If it wasn't for the fact that I get the same behavior with the other PhaseRunner controller, I'd suspect the controller.

I've even gone as far as changing the "control command source" in the PAS tab to read from the pedal sensor only, just to see if I was being faked out by readings from the twist throttle. It doesn't, though in that mode it does mean the twist throttle no longer works, as you'd expect.

If the powered wheel is offground, does that small motor current cause it to begin to spin?

That sounds like the small motor current is probably just this function, but that it is perhaps not set high enough to negate the drag of the motor itself (or perhaps the bike is just hard to pedal for some mechanical reason?).

No, the current doesn't cause a spin - judging from the dashboard, it's measuring only 0.06A. Also, to clarify, I'm seeing that without the "virtual electronic freewheeling" enabled - I had it turned on when I was first testing the trike out, but shut it back off as I started to try to limit the variables while troubleshooting.

 

[amberwolf]

As near as I can tell, yes. With the SH system, the PAS connects directly to the controller, not the harness. I do have the display set to match the 9-level settings, and assuming I change it up or down while I'm graphing the value on the dashboard, the controller does seem to be recognizing the change in assist level.

Does it matter whether you use the SH/display connected or not? The PR/BR should operate in max assist mode without the display, if i read those screenshots correctly.

I'm afraid you lost me with the "DBC" acronym, so I'm not sure if I'm following your question correctly.

Sorry, I just didn't want to type "display-based controller" a second time. But given the tests done, it sounds liek you've eliminated this issue already.


I expect we're missing something super obvious, but I can't think of anything else to check. It pretty much has to be a controller setting, but I don't see which one it might be--they all look like they'll do what you need. If you haven't already, you might give Grin a poke.

No, the current doesn't cause a spin - judging from the dashboard, it's measuring only 0.06A. Also, to clarify, I'm seeing that without the "virtual electronic freewheeling" enabled - I had it turned on when I was first testing the trike out, but shut it back off as I started to try to limit the variables while troubleshooting.

Well, I don't know what it means, but I doubt it has anyting to do with the PAS problem itself. You might have to ask Grin on that one, too.

 

[emcdermid]

Does it matter whether you use the SH/display connected or not? The PR/BR should operate in max assist mode without the display, if i read those screenshots correctly.

Hmm... I hadn't considered trying to run it headless. I can give that a try and report back, but it may be a couple of days.

I expect we're missing something super obvious, but I can't think of anything else to check. It pretty much has to be a controller setting, but I don't see which one it might be--they all look like they'll do what you need. If you haven't already, you might give Grin a poke.

Yes, I'm absolutely prepared to be kicking myself for missing the obvious once I figure it out. I have lots of experience with that.

I do in fact have a support email into Grin. I haven't heard back yet, though.