Axis Movement is Noisy

Owned by Adam Brunner
Last updated: Oct 04, 2023 by Sam Bollen
6 min read

Background

As motors rotate and the machine cuts, vibrations are created. While these are normal, they can resonate, making it sound like something is wrong. Loose sheet metal won’t affect your machine performance, but there are other electrical and mechanical components that should be inspected if the noise doesn’t subside.

Tools

  • Small flat-bladed screwdriver

Table of Contents

Secure loose sheet metal

Reason: There is loose sheet metal.

  1. Feel for vibration on the sheet metal by placing your hand on the enclosure, outside of the electrical cabinet, chip tray, or any other location you think is practical.
    If the vibration dissipates then the problem is not with the motors.

Reseat the connectors on the machine control board and motors

Reason: Control signals aren't reaching the electronic driver modules/servo motors.

  1. Power off the machine.

  2. Examine the data cables at the machine control board and the servos removing then re-connecting them to ensure they are seated.

    1. Machine control board: Degson style

      1. 424 (J13) (X-axis)

      2. 425 (J14) (Y-axis)

      3. 426 (J15) (Z-axis)

    2. Servos: Molex style

  3. Examine the power cables at the DC-BUS and the servos removing then re-connecting them to ensure they are seated.

    1. DC-Bus: Spade connector

      1. 210/211 (X-axis)

      2. 220/221 (Y-axis)

      3. 230/231 (Z-axis)

    2. Servos: Molex style

  4. Continue to the next troubleshooting topic.

  1. Power off the machine.

  2. Examine the data cable at the machine control board and the axes drivers.

    1. Machine control board: 26 pin IDC (ribbon cable); J6

    2. Stepper driver controllers: 10 pin IDC (ribbon cable)

      1. 423.1 (X-axis)

      2. 423.2 (Y-axis)

      3. 423.3 (Z-axis)

  3. Examine the power and control cables at the DC-BUS and the stepper driver controllers removing, inspecting, and re-connecting them to ensure they are seated.

    1. DC-Bus: Spade connectors

      1. 210/211 (X-axis)

      2. 220/221 (Y-axis)

      3. 230/231 (Z-axis)

    2. Stepper driver controllers: Degson style

      1. 211-214 (X-axis)

      2. 221-224 (Y-axis)

      3. 231-234 (Z-axis)

  4. If there is any discoloration, replace the cable and driver.

  5. Continue to the next troubleshooting topic.

PCNC 1100/770 only: Check connection of J2-5 and J2-6 jumper.

  1. Power off the machine.

  2. Examine the data cable at the machine control board and the axes drivers.

    1. Machine control board: 16 pin IDC (ribbon cable); J6

    2. Stepper driver controllers: 10 pin IDC (ribbon cable)

  3. Examine the power and control cables at the DC-Bus and the stepper driver controllers removing, inspecting, and re-connecting them to ensure they are seated.

    1. DC-Bus: Spade connectors

      1. 302/303 (X-axis)

      2. 304/305 (Z-axis)

    2. Stepper driver controllers: Degson style

      1. 302, 303, 308, 309, and 310 (X-axis)

      2. 304, 305, 311, 312, and 313 (Z-axis)

  4. If there is any discoloration, replace the cable and driver.

  5. Continue to the next troubleshooting topic.

  1. Power off the machine.

  2. Examine the data cable at the machine control board and the axes drivers.

    1. Machine control board: 26 pin IDC (ribbon cable); J6

    2. Stepper driver controllers: 10 pin IDC (ribbon cable)

  3. Examine the power and control cables at the DC-Bus and the stepper driver controllers removing, inspecting, and re-connecting them to ensure they are seated.

    1. DC-Bus: Spade connectors

      1. 203/204 (X-axis)

      2. 207/208 (Y-axis)

      3. 209/210 (Z-axis)

    2. Stepper driver controllers: Degson style

      1. 203, 204, 213, 214, and 215 (X-axis)

      2. 207, 208, 216, 217, and 218 (Y-axis)

      3. 209, 210, 219, 220, and 221 (Z-axis)

  4. Continue to the next troubleshooting topic.

Inspect the stepper driver controller

Reason: There's a defective axis driver module.

  1. See One Axis Won't Move (or Only Moves in One Direction), and Other Axes Move.

Inspect the DC-BUS capacitor (C1)

Reason: The C1 (DC-BUS) capacitor is defective.

  1. Power off the machine. Then, unplug the green power connectors on all of the axis drivers (X, Y, Z, and A).

  2. With the electrical cabinet door open, power on the machine.

  3. Examine the green LED on the DC-BUS board, and then twist out the Emergency Stop button and press the Reset button. The green LED should come on.

  4. Push in the Emergency Stop button.

    1. If the LED goes out in two seconds or less, the capacitor is defective and must be replaced. If the LED takes five seconds or more to go out, the capacitor is OK.

  5. If the results are not conclusive, power off the machine. Then, unplug the green power connectors from the axis drivers (if they're not already unplugged).

  6. Power on the machine). Then, carefully measure DC voltage on wires 202 (common) and 203 on the DC-BUS board.

    1. If there's a DC voltage of a nominal 65 Vdc (55-75), this indicates the capacitor is OK.

    2. If there's a DC voltage of a nominal 40 Vdc (35-45), this indicates the capacitor is defective.

  1. Power off the machine. Then, unplug the green power connectors on all of the axis drivers (X, Y, Z, and A).

  2. With the electrical cabinet door open, power on the machine.

  3. Examine the green LED on the DC-BUS board, and then twist out the Emergency Stop button and press the Reset button. The green LED should come on.

  4. Push in the Emergency Stop button.

    1. If the LED goes out in two seconds or less, the capacitor is defective and must be replaced. If the LED takes five seconds or more to go out, the capacitor is OK.

  5. If the results are not conclusive, power off the machine. Then, unplug the green power connectors from the axis drivers (if they're not already unplugged).

  6. Power on the machine. Then, carefully measure DC voltage on wires 300 (common) and 301 on the DC-BUS board.

    1. If there's a DC voltage of a nominal 65 Vdc (55-75), this indicates the capacitor is OK.

    2. If there's a DC voltage of a nominal 40 Vdc (35-45), this indicates the capacitor is defective.

  1. Power off the machine. Then, unplug the green power connectors on all of the axis drivers (X, Y, Z, and A).

  2. With the electrical cabinet door open, power on the machine.

  3. Examine the green LED on the DC-BUS board, and then twist out the Emergency Stop button and press the Reset button. The green LED should come on.

  4. Push in the Emergency Stop button.

    1. If the LED goes out in two seconds or less, the capacitor is defective and must be replaced. If the LED takes five seconds or more to go out, the capacitor is OK.

  5. If the results are not conclusive, power off the machine. Then, unplug the green power connectors from the axis drivers (if they're not already unplugged).

  6. Power on the machine). Then, carefully measure DC voltage on wires 212 (common) and 211 on the DC-BUS board.

    1. If there's a DC voltage of a nominal 65 Vdc (55-75), this indicates the capacitor is OK.

    2. If there's a DC voltage of a nominal 40 Vdc (35-45), this indicates the capacitor is defective.

Grease the motor coupling

Reason: The motor coupling needs grease.

  1. Power off the machine.

  2. Remove the motor from the noisy axis and set it aside temporarily.

  3. Remove the red bushing from the coupler and apply a small amount of silicone based synthetic grease to each side of the bushing.

  4. Reassemble the coupling and remount the motor to the machine frame.

Inspect the axis brake

Reason: The axis brake is failing.

  1. Ensure the machine is referenced. Put the brake into the maintenance position to manually disengage the brake. Check if the noise continues, if so proceed to the machine specific sections.

 

  1. With a multimeter, check for 24Vdc between wires 435 and 400 on the ECM board.

  2. If 24 Vdc is not present, the relay on the ECM board has failed and the ECM board needs to be replaced. If 24 Vdc is present, the brake has failed and needs to be replaced.

  1. With a multimeter, check for 65 Vdc between wires 326 and 327 that connect to the DC bus board.

  2. If 65 Vdc is not present between 326 and 327, check for continuity between J1-7 and J1-8 on the machine control board. If there is not continuity between J1-7 and J1-8, the relay on the machine control board has failed and the control board needs to be replaced.

  3. If 65 Vdc is not present, check wires 328 and 329 on the C1 contactor. If 65 Vdc is not present on 328 and 329, replace the C1 contactor. If 65 Vdc is present on 326 and 327, replace the Z-axis motor.

  1. With a multimeter, check for 65 Vdc between wires 326 and 327 that connect to the DC bus board.

  2. If 65 Vdc is not present, check wires 328 and 329 on the C1 contactor. If 65 Vdc is not present on 328 and 329, replace the C1 contactor. If 65 Vdc is present on 326 and 327, replace the X-axis motor.

  1. The PCNC 440 and 8L are not equipped with a brake