• Topic ID: id_17423028
  • Version: 3.0
  • Date: Apr 22, 2019 12:56:30 AM

CFHC Replacement

Prerequisites

Overview

This document provides the necessary steps to replace and configure the Common Fan and Heater Controller Assembly (CFHC) for imaging.

1 CFHC Assembly Removal

Procedure

  1. Move table to home position.
  2. Remove gantry right side cover.
  3. Stop the rotor of X-ray tube in case of Liquid Bearing Tube before HVDC off. Refer to Liquid Bearing Tube Rotor stop procedure for details.
  4. Turn off [HVDC ENABLE], [AXIAL DRIVE ENABLE] and [120 VAC ENABLE] switches on Service Switch panel.
  5. Remove power to system. See Equipment Service - Lockout-Tagout-PPE from Safety section.
  6. Remove gantry left side cover and gantry top covers, and slide the gantry front cover.
  7. Rotate gantry such that CFHC assembly is in 2 o'clock position.
  8. Engage rotational lock. See Equipment Service - Lockout-Tagout-PPE from Safety section.
  9. Disconnect four cables and two power cables from CFHC Assembly.
  10. Move cable bundle away from CFHC Assembly in order to avoid damage during CFHC Assembly removal / install process.
  11. Remove four screws, and remove CFHC Assembly from gantry.

    Figure 1. CFHC Assembly Mounting

2 CFHC Assembly Installation

Procedure

  1. Position CFHC Assembly on to gantry and fasten with four screws.
    note:

    when cable is connected, be careful NOT to cover the exit window.

  2. Connect four cables and two power cables to CFHC Assembly.
  3. Disengage rotational lock. See Equipment Service - Lockout-Tagout-PPE from Safety section.
  4. Restore power to system. See Equipment Service - Lockout-Tagout-PPE from Safety section.
  5. Turn on 120 VAC ENABLE, AXIAL DRIVE ENABLE, and HVDC ENABLE switches on Service Switch Panel.
  6. Press ESTOP RESET on Service Switch panel and wait until scan hardware is reset.

3 Setup, Checks, Alignments, and Calibrations

Procedure

  1. Gantry Rotation Safety Check
  2. Gantry Balance Procedure
  3. Turn off [HVDC ENABLE], [AXIAL DRIVE ENABLE] and [120 VAC ENABLE] switches on Service Switch panel.
  4. Install gantry front cover, gantry top covers, gantry left side cover and scan window.
  5. Turn on 120 VAC ENABLE, AXIAL DRIVE ENABLE, and HVDC ENABLE switches on Service Switch Panel.
  6. Press ESTOP RESET on Service Switch panel and wait until scan hardware is reset.
  7. Install gantry right side cover.