Gecko problem?

[bohica]

I am using Gecko 320's on my IH mill. A few days ago I powered up the mill and the Y axis servo immediately started moving the table, even though Mach 3 showed the limits needed reset. I disconnected the power to the Y axis and the other two axis behaved normally after resetting the limits.

It appears that the Y axis Gecko may have a problem. Is this a reasonable diagnosis or might there be another issue here?

[ger21]

Problem with the encoder?

[Cruiser]

i had this same problem a couple of times, till I found out that coolant was wicking in past the seal from the inside and getting my encoder wet. The ink on the encoder is bug spit & Berry juice so is easily damaged. It took a 10x loop to see the damage, then I dug in to find reason. I tried to wash off the encoder and really washed it off ! A new one and an improved seal on shaft fixed it.
earlier I had a sporadic craziness when trying to drive over the little damage spot on encoder.

[Bubba]

I also have had that problem with a Gecko 340 (Rev 0) and find that I need to keep a small light bulb in the cabinet or it will exhibit the same problem.

Just another thought

[bohica]

I pulled the encoder disk. This looks good, all lines clean and clear, no apparent foreign material on the disk.

[Cruiser]

Next check would be the wires from encoder to the gecko at the gecko. You may have one trying to break off at the pinch zone. After that I'd see if tuning changed within the gecko.