Planned Maintenance
- Planned Maintenance (PM) schedule overview
  Planned Maintenance (PM) tasks are developed from design requirement and operations/use assumptions to provide for the minimum required maintenance that maintains specified equipment design performance, high image quality, and safety. GE Healthcare (GEHC) advanced service methods are developed to maximize efficiency and use system access time as productively as possible, as described in the lifecycle maintenance statement.
- PM Procedures
  - Deionization procedure
  - Emergency Stop (E-Stop) planned maintenance
  - Checking InSite connectivity and ProDiags
  - Inspecting the cryogen vent
    Inspect the cryogen vent glass connection and clamp for damage, and weep hole for debris.
  - Checking InSite Remote Service Platform (RSvP) connectivity and ProDiags functionality
    Make sure the Remote Service Platform (RSvP) has connectivity and ProDiags is functioning properly.
  - Checking the oxygen monitor
    References to various Oxygen Monitor Subsystem Manuals.
  - Doing an MRU yearly service check (MRU, ERU, or EDU PM testing matrix)
    The model number is listed on the side of the MRU, ERU, or EDU. Refer to the appropriate vendor manual available from the online documentation library for applicable testing procedures.
  - Checking the pneumatic patient alert system
    Makes sure the stand-alone pneumatic patient alerts system is operating properly.
  - Checking and filling hydraulic fluid
    Checks and adjusts the hydraulic fluid level for the dockable patient table.
  - Body coil air flow functional check
  - Cleaning or replacing the body coil blower air flow filter
    Clean and/or replace the body coil blower air flow filter.
  - Checking the patient handling system with the laser leveling tool
    The proper alignment of the entire patient handling system is important for good image quality output from the GE MR scanners.
  - MDP power and ground and battery replacement label check
    MDP power and ground connections must be tight in order to avoid system failures.
  - Checking and adjusting the patient intercom functionality
    GOC Audio Assembly (GOCAA) controls are adjusted at factory for best sound quality. This document describes how to check and confirm volume and quality of sound heard from speaker in the magnet bore and from speaker at the Scan Control and Intercom Module (SCIM). Directions for sound adjustments are also provided if needed.
  - Patient table movement verification
    Makes sure the patient table controls operate correctly.
  - Cradle/table release block adjustment/cradle egress functionality
    Adjust the cradle release block position and the cradle release block retraction.
  - Doing the Leak Sensor functional check
    Test the functionality of the leak sensors.
  - Doing the UPM functional check (head and body)
    Do the UPM head and body functional check to make sure the measured RF power is within the expected range.
  - Dual drive quadrature tool
  - Doing DQA calibration
    The DQA tool determines proper gradient polarity and proper gradient wiring by scanning a series of axial and coronal images of the DQA III phantom.
  - Testing PAC leakage current
    Measure and record the PAC leakage current data.
  - Checking the gradient and system PDU power and ground connection
    PDU power and ground connections need to be tight in order to avoid system failures.
    - Applying LOTO - MDP
    - Tightening connections
    - Removing LOTO - MDP
    - Doing a check scan
      A check scan is done at the conclusion of many procedures. This functional check assures the unit is in good clinical working order.
  - Setting the time, time zone, and date
    Set the time, time zone, and date in Guided Install.
  - Replacing and cleaning the blower box filter
    Clean and replace the blower box filter.
  - Heat exchanger cabinet installation and FRU replacements
  - Installing and checking ECG leads
    Checking ECG leads.
  - Checking the GOC battery replacement
    Check the battery replacement sticker on the GOC.
  - T-file cleanup
  - Inspecting the cryocooler adsorber
  - Checking the RF screen room door
    Make sure the RF screen room door is functioning correctly.
  - Cleaning and replacing P-port receptacles (ODU connectors)
    The P-Port receptacle must be cleaned and lubricated on each of the system P-ports.
  - Doing a compressor pressure check
    Do a check of the cryocooler compressor supply pressure.
  - GE OR-compatible MR table option
- E-Reporting tool

Discovery MR750 3.0T System Service Methods
5690009-2EN Revision 4
Object ID: 00000018WIA304A4510GYZ
Topic ID: id_2004634 Version: 4.4
Date: Oct 28, 2021 5:51:40 PM

Tightening connections

About this task

When tightening connections, make note of any that are very loose (for example, two full rotations or more on a single lug). Record this as part of the ePM documentation.

Procedure

Open left front door of the PGR cabinet to expose the front of the PDU.

Figure 1. Tighten Connections
Flip up the input power block lid to expose the connections as shown in the illustration below. Test the connections with a multimeter to make sure there is no AC voltage prior to continuing.
Tighten the incoming power and ground connections on the input power block of the PDU with a socket wrench with a 3/16 hex key extension.

Figure 2. Tighten Incoming Power and Ground
Remove the front PDU panel to expose connections to CB1.
1. Remove the four screws on the circuit breaker guard. Save the screws.
2. Remove the 13 screws securing the front panel. Save the screws.
Figure 3. Remove the screws
Remove the front PDU panel to expose connections to CB1.

Figure 4. Location of CB1
Tighten the L1, L2, and L3 connections at CB1 inside the PDU.

Figure 5. L1, L2, and L3 connections

Finalization

If any of the connections were very loose (for example, two full rotations or more on a single lug), record this as part of the ePM documentation.
Reinstall the PDU front panel if it was removed.
Make sure all subsystems have powered up successfully.