Hi Ben,

From the information you provided its hard to tell if there is a configuration problem or a noise/cross talk problem.

I find when something doesn't work as expected its better to dig into it to find the reason rather than swapping things around.

It wouldn't be uncommon for a disconnected floating encoder input to count like an adjacent encoder.  Especially if your ribbon cable or other wiring is long.  But if connected to an encoder it should not count.  Possibly you had both axes configured to the same encoder?  SnapAmp encoder inputs are high impedance with no termination.  If you have noise issues you might add termination by adding something like a 150ohm resistor across each of the + and - signals.  This should be as close as possible (several inches) from SnapAmp.

A common problem is to have noise on the index pulse signal.   Start with the AutoPhase program and make sure the report makes sense every time.  The positions should all be 1 rev of counts apart (within several counts). 

In order for the motor to move correctly and not fault the commutation must be working correctly.  After a power cycle a phase find operation must be performed to set the encoder to the physical rotor position.  Normally a search for the index pulse is performed to do this.  It isn't clear if you are doing this.

We can connect in and help you with configuration, training, tuning, troubleshooting but for this we charge a fee.

HTH
Regards
TK

 

Hi Tom,

For the past three days we have had a hard time testing and tuning our 2 Teknic Hudson, brushless servo motors, labeled X & Y axis. The encoder indexes of both motor are connected to optos temporarily for the tuning process. 

The first day, we had our X axis connected into differential input/Encoder 0, and the encoder's index into pin 32 (Bit 72). The Y axis was connected to differential input/Encoder 1, and the encoder's index into pin 34 (Bit 73). The motors would not operate. As soon as we moved the Y axis' encoder index 1 opto over (pin 36 - bit 74), it worked perfectly fine. We were able to use the AutoPhaseFind c program and find all of our motors commutation offset successfully, and eventually the day came to an end.

The second day, we came back and tried to tune the motors, they would not operate in Step Response or AutoPhaseFind.c. Nothing was touched, altered, or breathed on since the day prior. Even more odd, when rotating the X axis by hand, the Y axis position in the Axis menu (KMotion), would indicate identical movement - even if the Y axis was unplugged! We decided to move the Y axis to differential input/Encoder 2 so that the two encoders weren't adjacent, and once we did both motors worked fantastic - able to experiment with tuning in Step Response.

Today we came in and it was the same story as the past two days, no movement, yet nothing altered to the system between now and yesterday. I disconnected all of the wires from the breakout board and reconnected them, and we were finally able to get some movement in the AutoPhaseFind c program. However, once we attempted to use our optimal motor tuning settings from yesterday, the motor would go into fault mode. Anything close to the settings would also fail. 

Tom, I know this is quite a bit of writing but I would sincerely appreciate any guidance or support.

Thanks you!

With best regards,

-Ben