[pchfurniture]

Had no response to z axis one morning. After obvious troubleshooting determine gecko drive was bad as I switched out drives with the x and the z worked fine,
Got new drive in today and after powering up the z axis wants to take off. I assume this is the optic encoder as the dro did not move.
Am I right in my assumption?

[bhurts]

Most likely if you have both the encoder and motor hooked up its reverse feedback. You need to do one of two things to fix it. Either reverse the 2 wires going to the motor or switch the encoder a and b signals around at the drive. Do not do both.

Ben

[pchfurniture]

nope....just switched the encoder a & b signals and still takes off.....
anything else I can try?

[bhurts]

From your first post I see you switched drives with x and z. It's not clear what you switched. Did you try the y motor with the other drives? If yes and it works then it's not the encoder. If it still runs away while connected to the other drives then the encoder could be the problem.

Ben