VMC40 X axis motion locks up controller

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03-29-2024, 06:13 PM
GlenMc

VMC40 X axis motion locks up controller

No issue with Y & Z, only the X axis motion will cause a lunge, the video scrolls message "CLEAR AN EMERGENCY STOP CONDITION", the control locks up, the X axis control board (1010-4) LED blink changes to once every 4 seconds, the LED on the Computer Interface PCB (1030-1B) changes from blinking to solid on, the Spindle Control board (1010-1) led stops blinking and stays on with a flicker, Y & Z control board LEDs continue blinking twice per second. Sometime the control resets itself or I can press the reset button on the X axis control board to return to normal. The LEDs on the axis control boards and the spindle control board blink twice per second, Jog will reset the drives, I can move Y & Z but X motion causes the problem every time. A handle motion of .01" causes a physical movement of .027", display only shows .01" movement, subsequent movements cause the problem.
I have swapped X & Y control boards and the problem does not follow, I swapped amplifier control cards and problem does not follow, I swapped the Clock board (1020-0) and problem remains, I replaced the resolver and the problem does not change. Voltages on mother board measure 5.17vDC, 12.39vDC, and -12.06vDC. The X axis ball screw turns smoothly.
Any ideas?
03-31-2024, 08:24 AM
Mhook

Quote:

Originally Posted by GlenMc

No issue with Y & Z, only the X axis motion will cause a lunge, the video scrolls message "CLEAR AN EMERGENCY STOP CONDITION", the control locks up, the X axis control board (1010-4) LED blink changes to once every 4 seconds, the LED on the Computer Interface PCB (1030-1B) changes from blinking to solid on, the Spindle Control board (1010-1) led stops blinking and stays on with a flicker, Y & Z control board LEDs continue blinking twice per second. Sometime the control resets itself or I can press the reset button on the X axis control board to return to normal. The LEDs on the axis control boards and the spindle control board blink twice per second, Jog will reset the drives, I can move Y & Z but X motion causes the problem every time. A handle motion of .01" causes a physical movement of .027", display only shows .01" movement, subsequent movements cause the problem.
I have swapped X & Y control boards and the problem does not follow, I swapped amplifier control cards and problem does not follow, I swapped the Clock board (1020-0) and problem remains, I replaced the resolver and the problem does not change. Voltages on mother board measure 5.17vDC, 12.39vDC, and -12.06vDC. The X axis ball screw turns smoothly.
Any ideas?

hi
make sure that the molex sockets at the bottom of the motherboard are clean and connected
04-01-2024, 01:39 PM
GlenMc

Re: VMC40 X axis motion locks up controller

Thank you Mhook, I did as you suggested. I also wrung out the cables for the motor and didn't find any issues, but I did notice a resistance measurement of 144 ohms for the X axis tachometer, 68 ohms for Y axis, and 84 ohms for the Z axis tach. Could I have a tachometer issue?
04-01-2024, 02:19 PM
Mhook

Quote:

Originally Posted by GlenMc

Thank you Mhook, I did as you suggested. I also wrung out the cables for the motor and didn't find any issues, but I did notice a resistance measurement of 144 ohms for the X axis tachometer, 68 ohms for Y axis, and 84 ohms for the Z axis tach. Could I have a tachometer issue?

i checked for me and it was similar to your machine/ i think
the lenght of the cable cause it may increase ohm resistance!
the x axis cable is longer than others axis
If the X axis motor swapped with Y axis, you would be sure what the problem is
04-01-2024, 08:12 PM
machinehop5

Re: VMC40 X axis motion locks up controller

Quote:

Originally Posted by GlenMc

Could I have a tachometer issue?

...If, you have DC Axis drives ....than yes. It sounds like a Tach issue. Dirty brushes, carbon dust, etc. or even possible just bad Tach.

DJ
04-03-2024, 03:27 PM
GlenMc

Re: VMC40 X axis motion locks up controller

I thank everyone for taking the time to read and reply to my situation. I did as suggested and I swapped the X axis and Y axis motors without installing them, but the problem did not follow the motor.
I just swapped the 1010-4 Axis Control PCB with a 1010-5A Axis Control PCB from a Fadal 4020 and the problem continues, so I swapped them back.
I observed repeatedly when moving only the X axis, the controller locks up with the "CLEAR AN EMERGENCY STOP CONDITION". I can press the Emergency Stop button and the control unlocks. But as soon as I release the E-Stop the control locks up again.
Not until I press the reset button on the 1010-4 X Axis Control PCB will the controller return to normal operation.
I'm going to take Mr. de Caussin's advise and send the circuit boards to him at NXGEN CNC for evaluation. I'll let you know what I find out.