ATC Driver Motor Fault on Z-Axis/Input 5 Constantly On

[Art Sign Works]

For the last week, with growing frequency, my ATC Alpha will quit during runs and give a driver motor fault on the Z-axis. I have rewired the motor, re wired the prox switch on the Z-axis and even reloaded the control software....at a loss now. Also, should input 5 be constantly lit-up on the software? Please help. Thanks.

[Brady Watson]

No input 5 should not be on all the time. IIRC, it is the Z prox switch on ATC machines. Re-check the wiring for that & make sure nothing metal is hanging down in front of it when off the Z target - otherwise it will never sense the target, the Z can over-shoot the target and bump the hard stop - and cause a motor driver fault.

-B

[Keith Larrett]

Also, should input 5 be constantly lit-up on the software?

My input 5 light is always on. It only turns off when the z-axis proxy switch is hit. Input 2 and 3 lights are always off and only turn on when the x or y-axis proxy switches are hit.

If you look under VN (values - input/output switch mode) you will see that switch 2 and 3 are nominally closed while switch 5 is a standard switch.

[Keith Larrett]

I'm not entirely clear from your description, but I think I went through a similar issue. ShopBot support was very helpful in tracing the issue, although it took a while to finally isolate the problem.

We replaced, in order, the z-prox switch, the z-prox switch cable, the controller card and ribbon and then finally the main control board. Once the main control board was replaced the problem went away.

The issue was intermittent which made it very difficult to trace.