• Topic ID: id_11039098
  • Version: 3.0
  • Date: Apr 9, 2020 8:48:58 PM

Cam Encoder Harness Replacement

Prerequisites

Procedure

  1. Remove gantry covers as required.

    Refer to Parts Replacement > Gantry > Enclosure > (Cover Removal Procedure).

  2. Turn OFF all three (3) gantry service switches (Axial Drive, HVDC, 120 VAC).
    • danger
    • CRUSH HAZARD.
    • UNEXPECTED GANTRY ROTATION CAN CAUSE SERIOUS INJURY.
    • Never service the gantry with the axial drive enabled. Use the gantry rotation lock to lock out gantry rotation. See safety menu of Service Document gui for appropriate procedures.
  3. Position the gantry with the XRT at 6 o'clock.
  4. Remove the top cover from the Collimator by removing the five pan head M4 mounting screws that have spring washers.
  5. Remove the three red cap/plugs.
  6. Remove the driver cover on motor mount assembly by removing the two pan head M4 screws with spring washers.
  7. Disconnect the connector between motor drive and motor.
  8. Disconnect the ground shield lead.
  9. Use a flashlight aimed through the cap/plug holes to see the screw in the coupler.
  10. Rotate the motor until the screw is visible and can be loosened on the flexible motor coupler.
  11. Loosen the flexible motor coupling screw.
  12. Take out the four hexagon socket M4 screws holding the motor to the Motor Mount Plate.
  13. Remove the motor.
  14. Remove the four countersunk M6 cap screws for the Motor Mount Plate.
  15. Remove the Motor Mount Plate.
  16. Disconnect the harness.
  17. Unplug harness from encoder by depressing locking mechanism and pulling out.
  18. Remove the screw for the harness shield ground lead.
  19. The harness can now be removed and placed in container for return.
  20. Install the new harness and ensure it is locked in position.
  21. Tighten the screw for the harness shield ground lead.
  22. Connect the harness.
  23. Install the motor mount plate.
  24. Torque the four countersunk 6x12mm cap screws to 17 ± 1.5 N-m.
    note:

    Conversion Factor: 1 ft-lb = 1.356 N-m

  25. Install motor & tighten the four hexagon socket screws to 3 ±0.3 N-m.
  26. Tighten the flexible motor coupling screw to 1.5 ±0.15 N-m.
  27. Connect the ground shield lead.
  28. Connect the connector between motor drive and motor.
  29. Install the driver cover on motor mount assembly, making certain that the two tabs engage with the slots in the filter PWB Bracket.
  30. Tighten the two pan head M4 screws with spring washers.
  31. Replace the top cover of the Collimator using the five pan head mounting screws with spring washers and tighten.
  32. Install the three cap/plugs after all hardware has been torqued.

Finalization

  1. Perform CAM A/B Encoder Check.