GMAC 10T CA v.3 speedometer readings off by a lot

[retrocycler]

Hi,

I'm building up a bike with GMAC 10T and a PhaseRunner (PR) all hooked into a Cycle Analyst v.3 (CA). My bike isn't on the road yet, I'm still just setting it up, with bike in a stand with rear wheel/motor turning freely for testing.

The GMAC motor appears to have 80 “pole pairs” which ought to be the value I should set in the CA speedometer settings. But the CA appears to only allow a value up to 30. Thus, I cannot get proper speed readout on the CA. Has anyone else encountered this problem?

(... and plugged into the utility software, the PR does appear to report the correct wheel speed to the software, a little over 25MPH max, judging from eye-balling the spin/rpm of the motor/wheel)

thanks for any tips!

 

[ATinkerer]

My GMAC literature says 6 speed pulses/revolution.
The 16 magnetic pole pairs (80 effective has to do with motor drive settings.

 

[amberwolf]

The GMAC probably has a white wire for speedometer output. If you use this at the CA's speedo input, then the above "6 pole" setting should work.

If you're using one of the multipin waterproof connection harnesses for the whole system, then the signal already goes to the PR, and you change the PR's settings to not echo the hall signal out, but rather do the speedo wire signal:
https://www.ebikes.ca/product-info/phaserunner.html#cables-and-connectors

Speed/Thermistor Pass Thru - JST-SM: The extra 2 pin female JST-SM plug is present in order to hook up additional inputs to the WP8 Cycle Analyst plug. If the motor has a built in temperature sensor, this signal can be fed to JST Pin1 to show motor temp on the CA3 and enable thermal rollback. Geared motors that have an internal speed sensor should use Pin2 as a pass-thru of the speedometer signal line to get speed display on the CA3. In this case, the setting at address 174 "HDQ Replicating Hall" should be unchecked. For direct drive motors, the motor speed will go through automatically to the CA3 as long as "HDQ Replicating Hall" is selected.

 

[retrocycler]

Thank you friends! Setting the CA to 6 poles per revolution did the trick. Now the readings look appropriate. My PS is the L10, with the multipin connector. There is a two-pin terminated cable that goes to the CA, but it only has one pin (in a two pin connector!), and it apparently carries the motor temperature signal.

 

[haulincolin]

I have a weird variation on this problem.

Phaserunner with MT plug using a L1019 adapter harness to connect to a GMAC. The harness has a separate 2 pin JST connector with white and grey wires at the controller end, but there is nowhere to plug it in. I'm thinking I just need to cut the speedo wire out of the CA plug and make a new plug to connect it to the white wire. Is there a different way I'm supposed to do this? I feel like there might be a simpler solution that I'm just overlooking...

 

[amberwolf]

does this help?
https://endless-sphere.com/forums/viewtopic.php?f=2&t=107259&p=1576136&hilit=phaserunner+speed%2A#p1576136