[rlockwood]

Recieved my g540 back from gecko on Saturday from a repair on the y-axis-- which went down mid-program. Hooked it up and everything seemed great. Ran good all weekend... X-axis went down this time-- again mid program. With the y-axis, I had no holding torque and it wouldn't come out of fault. This time, it comes out of fault and has holding torque, but no motion. all other axes function properly, and no motors function when hooked to x-axis drive. Also, the x-axis motor functions on any other drive.

Is it time for another trip to gecko already? If so, any ideas why its failing so rapidly?

The note from gecko for the first repair suggested i'd reversed polarity on the drive, which doesn't seem likely mid-program. Repair was for a cooked mosfet.

Running linuxcnc, keling 381oz steppers, keling 48v supply, 3.3k resistors. No apparent shorts on wiring.

i'd appreciate ANY help I can get here, I can't come up with anything wrong on my end-- but I cant imagine the failure rate on gecko's is anything close to this high

[sizala]

hellow Rolckwood,
the same thing was happened with me but on china TB65 ebay board.

i dont know that you have any knowledge of electronics or not, so let me give you a small hint that what you can do to solve this problem and to stay away from this type of problems in future.

stepper drivers mainly work by 3 signal
1. step
2. dir
3. enable

so if your motor stays in holding position and dont move a bit, then the driver is getting the "enable" signal , and there is some problem with the "step" signal. so check the wires from that.
and the same things go for all 3 signals.

and get a optocoupler board from ebay or make your own with "optocoupler pc817". (i made for my self). it will help you save your driver and PC's port.

[rlockwood]

After sleeping on it, I probably ought to try a different parallel cord. I'm hoping the drive simply isn't receiving step pulses

[dhelfter]

I just sent 4 g540's back for very similar problems. Not sure what is going on Have used about 20 of these th last 3 months for machines we build, then wam 4 in a row with varies fault\movement problems. 100% sure polarity was not reversed, and using tried and proven components. Look forward to finding out what the problem is.
Dan

[rlockwood]

Figured I should pop back in and give an update, picked up a new parallel cord and all is right with the world.

I have a feeling it was to blame for both issues, but its been a few days with no issues.