Author Topic: Smart bob not seeing Z limit switch.  (Read 814 times)


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Smart bob not seeing Z limit switch.
« on: April 01, 2020, 07:48:14 PM »
I touched the frame of my cnc router today and felt static. The machine is grounded but the spindle stopped in one position. I had to reboot a bunch of time to get it working but now that doesn't seem to help. I can home manually with jogging but when i try to "references all axis" (Mach 4) I get an error saying that Smart Bob can't tell if the z axis is on the home switch or if it hits the home switch. What should I do?

Thank you.


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Re: Smart bob not seeing Z limit switch.
« Reply #1 on: April 02, 2020, 12:27:42 AM »
What is the exact error message?  Go to the Mach4 "Machine Diagnostics" tab and look at the limit switch indicators for the motor(s) on your Z axis.  Do they turn on/off (green/red) when you press and release the limit switch (or jog the machine to where the limit switch SHOULD trip)?  If not, can you move that limit switch to a different input on the SmartBOB?  And which model of SmartBOB are you using?