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 leak sensor functionality test
    - System power on
    - Starting up the host computer
      How to start the host computer.
    - 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.
  - 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.
  - 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: 00000018WIA30363730GYZ
Topic ID: id_2012135 Version: 4.3
Date: Oct 11, 2021 6:27:53 PM

Doing the leak sensor functionality test

Procedure

Shut down the system by clicking the arrow on the Tools High Level Access tab, select System Shutdown, and click [Yes] to confirm the shut down.
Place all circuit breakers in the OFF (down) position.

Figure 1. Circuit breakers on PDU

Power on the Gradient 48V switch in the PDU. Verify that all other circuit breakers are OFF.

Note: If the PDU main breaker trips when you power on the gradient 48V switch, it indicates that the leak sensors are in contact with leaked coolant.

For details, see Leak detection sensor theory and troubleshooting
Verify that the AUX board (or PEM) power is ON.
Put a small drop of water on the leak sensor strip.

Figure 2. Leak sensor strip location
The PDU main circuit breaker should trip (power down) within two minutes of putting the drop of water on the leak strip. This verifies that the leak sensor is functioning properly.

If it is not functioning properly, refer toLeak detection sensor theory and troubleshooting.
Dry off the leak sensor and surrounding sheet metal.
Before powering on the PDU, verify that the leak sensor strip is clean and dry.