- Topic ID: id_17479558
- Version: 1.0
- Date: Aug 28, 2018 3:54:47 PM
Home Flag Sensor Board Assembly Replacement
Prerequisites
Overview
This procedure defines the necessary steps to replace the home flag sensor board.
1 Preparation
Procedure
- Move the table to the home position.
- Remove gantry right side cover.
Refer to
- Turn OFF the Axial Drive and HVDC switches on the gantry’s Service Switch Panel.
- Rotate the gantry to the proper place for easier access to the sensor board.
- Turn OFF the 120 VAC switch on the gantry’s Service Switch Panel.
- Remove the gantry left side cover, top covers and front cover.
2 Replace Sensor Board or Sensor board assembly
Procedure
- Disconnect the harness from the sensor board.
- Using a 3 mm hex wrench remove the M4 screws attaching the sensor
board to the bracket assembly.
Figure 1. Home Flag Sensor Board

- Replace the sensor board installing the screws previously removed, tightening 1/4 turn past seated.
- Reconnect cable to the sensor board.
3 Restore Gantry
Procedure
- Slowly rotate gantry by hand and adjust flag position to pass through the center of the opto-sensor on the sensor board. The home flag is next to the 48V Power supply.
- Make sure that the flag is centered in the opto-sensor on the
sensor board (Figure 2) and does not make contact with it.
Figure 2. Position of Opto-sensor and Home Flag

- If necessary, adjust by loosening the screws and slightly shifting the board.
- Perform the Checking the C-Pulse procedure.
- Install the gantry front cover, top covers and left side cover.
Refer to
- Enable 120 VAC HVDC and Axial Drive service switches from the service switch panel. Press the table drives enable button on the lower right corner of the service switch panel.
- Install the gantry right side cover.
4 Finalization
Procedure
- Perform a System Scanning Test from the Functional Checks menu of the service manual to ensure system operation.