Cycle Analyst : Human Power value dropping to zero

[sorg]

Hi !

I have a CAv3 and an erider T17 torque sensor.

The sensor seems properly set up in the CA, and in the set-up menu i can read consistent torque value.

While riding the Human Power value seem unstable and tend to suddenly drop to zero (which in turn deactivate the proportional motor assistance). After a couple of minutes, realistic human power values are coming back.

The torque-based assistance is pretty unusable at the moment.

Do you have any idea of what could be the issue ?

 

[slaphappygamer]

Check the PAS setup settings. Do you see regular magnet recognition when you rotate the cranks? If no, then you could have a loose connection. I usually find a loose/broken wire causing issues like this.

Is it safe to assume that the torque sensor is connected to the CA and not the controller?

 

[sorg]

Yes the pas/torque sensor is connected to the CA.
Pass signal looks fine but I'll check the connections.

 

[amberwolf]

IIRC you can monitor the actual signal levels / pulses / direction of the torque and cadence sensors within the CA setup menus. If you do that while riding then you can keep an eye out for a loss of or change of signal.

It's likely that the CA won't process the data and create a throttle signal from it while in the setup menu, so you'll just be on pedal power during this time, no motor assist controlled via pedals.

Otherwise, assuming you don't find any connection issue: does the cutout appear under any specific repeatable riding conditions? If so, you can see if they are something that affects the actual sensor operation, etc.

Or, switch to the Diag screen (one press of left button on CA) and see if you get any capitalized letters during these times. Those indicate a limit has been reached, and so the CA will do whatever that limit is set to trigger.