I realize how crazy this sounds. I'll greatly appreciate insight.
I'm on my second bike build using a VESC 6 MK V. The first build used a 24V battery and works great. This one uses a 48V battery and has had problems for days.
The control inputs are from a Sempu T9 pedal sensor. Torque is on ADC1 and cadence is on ADC2. (I'm only using torque at the moment.) The T9 requires 8-12V so I run the 5V signal from the COMM connector through a 9V step-up converter. (https://www.pololu.com/product/2116) The signal on ADC1 should be 1.5-3.0V.
It would work great on the stand but as soon as I took it out for a test ride, it'd get wonky. I finally realized that the problem was that I zip tied the cable when I was ready to go out.
I can watch the ADC app and see the signal on ADC1 drop near 0V when I kink the cable to the pedal sensor. I tried a fresh cable and another 9V converter and ensured that the connections were well insulated (with heat shrink tubing). Same problem.
I connected a fresh pedal sensor. Same problem.
I brought it in to my bench and tested it. I could not replicate the problem. The only difference was that I used a little 24V battery instead of the 48V battery on the bike.
I took everything back to the bike and connected to the bike's pedal sensor and motor. Using the 24V battery from my bench, it worked perfectly; kinking the cable had no effect. I tried and tried but could not get the voltage to dip. I switched to the 48V battery and the kinking caused a problem again.
I just received a new 48V LiFePO4 battery so I tried it (instead of the Li-ion battery). Same problem.
This makes no sense to me. The cable is apparently alright...except when the battery is 48V. But I'm using the 5V output so that shouldn't vary, right? And why would kinking the line matter anyway unless there's a defect in it?
I'm desperate and thinking about throwing a capacitor on it but if the 5V output is clean, this shouldn't be necessary. (And I still don't see why kinking the cable would have any effect.)
Help???