Erider torque output issues with CA3

Hello!
I've recently installed an eRider T9 on my conversion ebike and I've been having issues trying to make the torque assist mode work in CA3 with it.
This image shows that the CA3 does appear to be reading the torque levels properly; however no matter what I tweak in other settings I can't get it the torque response to trigger the motor assist when pedalling.

This CA3 unit was working fine with a basic PAS unit beforehand and the throttle output still works fine so I don't believe this is a CA3 or controller hardware related issue. The only unorthodox thing about the current configuration is that the eRider is being powered by an external buck converter since that's what Grin recommends for 72 V setups.
Here's my current config on the CA3:

Are there any obvious config errors I'm not seeing or anything I should tweak?
Any help with this issue would be much appreciated! :thumb:

I'm sure it's the case, but confirming just in case that you are doing your testing with the CA using preset 2 or 3, correct?

E-HP said:

I'm sure it's the case, but confirming just in case that you are doing your testing with the CA using preset 2 or 3, correct?

Click to expand...

Yep! Have a little aux button to swap on the go between them.

Is it correctly detecting the cadence portion of the sensor toggling as the cranks spin, and in the correct direction?

If so, does the system work correctly when changing it to not use the torque sensor, but only the cadence sensor portion?



Which firmware version does the CA have installed on it?

(IIRC, only the latest version (3.14?) will operate from torque only, so if the cadence sensor isn't doing what it should, it won't send a throttle signal out.)

In the diagnostic screen (one left of the main?) is there a throttle signal shown on ThOut, while testing the torque sensor?


Also, not having used an Erider yet I looked it up, and if I understand their spec listing I think the T9 uses 36 pulses per rotation for the cadence sensor, per their page linked below. I'm not sure if that makes any difference for your specific issue.
https://www.erider.com/#/sensors

Torque Sensor ★ ERS-T9
Operation Principle Torque
Signals 36
Input Voltage 8 ~ 15V
Output Voltage 1.5 ~ 3V
Operation Temp. - 20 ~ + 45 ℃
Shaft Standard JIS
Case Materials Aluminum
Weight 470 ~ 520g
Wire Length 200mm
Shaft Length [ 150, 155, 162, 165, 182 ]
BB Width [ 68, 73, 80, 83, 100 ]
Chain Line [ 47.5, 50, 53.5, 55, 63.5 ]
Mounting Position Bottom Bracket
Connector Type ( Waterproof ) JL-F-Z609AG
Wire Routing BB Side, Left

Click to expand...

amberwolf said:

Is it correctly detecting the cadence portion of the sensor toggling as the cranks spin, and in the correct direction?

If so, does the system work correctly when changing it to not use the torque sensor, but only the cadence sensor portion?



Which firmware version does the CA have installed on it?

(IIRC, only the latest version (3.14?) will operate from torque only, so if the cadence sensor isn't doing what it should, it won't send a throttle signal out.)

Click to expand...

I did actually try to swap to the basic cadence mode on the medium preset and it still wasn't working either. The CA is on 3.14 but yeah it could definitely be the cadence sensor.

Part of the issue is I bought it direct from China rather than from Grin so it didn't come with the wiring harness preconfigured so I'm wondering if I may have flipped pins accidentally. For reference this is how I have my harness configured currently and the pinouts Grin and eRider both have listed:


View attachment 1
As you can see both green and yellow are marked as being the cadence pins in the eRider docs which makes this somewhat hard to parse. I might try swapping yellow and green tomorrow and see if that resolves the issue.

In the diagnostic screen (one left of the main?) is there a throttle signal shown on ThOut, while testing the torque sensor?

Click to expand...

Would that be found under the throttle settings or PAS settings? I'm having trouble locating that indicator.

And yep it's the 36 pulse version of the eRider. For some reason older versions of the CA3 firmware only go up to 32 poles. I emailed Grin about it and they said to just set it at 32.

NixyMouse said:

I did actually try to swap to the basic cadence mode on the medium preset and it still wasn't working either. The CA is on 3.14 but yeah it could definitely be the cadence sensor.

Click to expand...

That would be my bet if it won't work on cadence only.

The good news is that if for some reason teh cadence sensor is simply not working, you don't need the cadence sensor that's built in, since you probalby have your old cadence PAS sensor laying around...if so, you can wire that in instead, and use it for the cadence part.

Also, IIRC 3.14 has a way to not require cadence detection at least at startup, just torque, but I haven't yet used this feature so I do not know how to set it up for this. There should be info on it in the last few pages of the CAv3 beta thread, though (and presumably on the Grin site or in the notes that come with the FW when using the CA setup program on a computer.

Part of the issue is I bought it direct from China rather than from Grin so it didn't come with the wiring harness preconfigured so I'm wondering if I may have flipped pins accidentally. For reference this is how I have my harness configured currently and the pinouts Grin and eRider both have listed:
IMG_20221016_200000.jpg
Screenshot 2022-10-16 at 20-26-29 Cycle Analyst V3 - Grin Products - Product Info.png
Screenshot 2022-10-16 at 20-25-05 H5f4a80bedb75436ea715285004685c2cp.jpg (JPEG Image 931 × 817 pixels).png
As you can see both green and yellow are marked as being the cadence pins in the eRider docs which makes this somewhat hard to parse. I might try swapping yellow and green tomorrow and see if that resolves the issue.

Click to expand...

Worth a try. IIRC one wire is the direction signal, which is a steady signal (the one you're setting the Fwd = 5v or 0V for in the sensor setup), and the other is the actual cadence signal, which is a pulse for every magnet pole that passes it.

In the diagnostic screen (one left of the main?) is there a throttle signal shown on ThOut, while testing the torque sensor?

Click to expand...

Would that be found under the throttle settings or PAS settings? I'm having trouble locating that indicator.

Click to expand...

Neither one. It's in the "running" screens, one screen left of the main screen. It shows throttle volttages in and out on top, and shows limit flags on the left bottom, other numbers on the right.
https://ebikes.ca/product-info/grin-products/cycle-analyst-3.html#DisplayScreens
https://ebikes.ca/pub/media/wysiwyg/V3CA_Screen11.jpg

And yep it's the 36 pulse version of the eRider. For some reason older versions of the CA3 firmware only go up to 32 poles. I emailed Grin about it and they said to just set it at 32.

Click to expand...

Yeah, it'll work it just will think the sensor is spinning faster than it really is, I think. (maybe it's slower...me and math don't always get along).

Apologies with the delay reporting back. I was waiting for a pin remover to swap around the pins. Finally got it today and played around with the pins. Sadly no combination of wires resolved the issue. Swapping yellow and green did nothing, also tried just connecting either pin to the RPM pin did nothing either.

Going to try contacting Grin's support to see if they have any suggestions. Worst case I'll try to the torque only mode or stick a cadence sensor.

Will update the thread for future reference in case anyone else runs into a similar issue in the future

Hi NixyMouse. Did you ever get this problem solved? I'm having similar issues. I can see a torque response and voltage response in the CA in the set up menu but I can't get PAS to work at all. Cadence doesn't work at all either so I think that's the problem. I may try reinstalling the unit and torquing it higher but we'll see. I'm going to also ground the battery as that solves a lot of EMI issues apparently. But I don't see why the cadence portion isn't working at all.

I am also unable to get torque sensing to work reliably with a CA3, eRider T9, and a 72V battery.

Where did you find this documentation from grin about the buck converter?

Thanks!

I added a Mini 360 set to 10.10V on the output on the red and black wires on this torque sensor wire and it seems to have fixed the problem.

The 70 Nm per Volt now is way off, however, I set it to 43, but it still seems a bit weird.