• Discovery MR750 3.0T System Service Methods
  • 5690009-2EN Revision 4
  • Object ID: 00000018WIA3023D030GYZ
  • Topic ID: id_12374002 Version: 1.15
  • Date: Oct 11, 2021 3:47:40 PM

Replacing CPC MNS amplifier components

Describes the replacement procedures for the major components of the CPC cabinet.

Prerequisites

Personnel requirements
Required personsPreliminary requirementsProcedureFinalization
1-120 minutes20 minutes
Tools and test equipment
ItemQuantityPart numberManufacturer
Hoist Service Kit15196226-
Hoist Beam Adapter Bracket15750811-13-
Replacement parts
ItemQuantityPart numberManufacturer
DV Combiner FRU Collector (Top), Gen115411744-8-
DV Power Amplifier FRU Collector, Power Amplifiers #1 and #2, Gen11 each5411744-6-
DV Driver Amplifier FRU Collector, Gen115411744-7-
DV Master Power Supply FRU Collector (Bottom), Gen115411744-9-
3T MNS RF Amplifier (Power Amplifier), Gen215750811-8-
3T MNS RF Amplifier (Power Supply), Gen215750811-7-
Safety

Before working in any GE Healthcare MR suite or performing any GE Healthcare service procedure, you must:

  • Have read and understood all hazard conditions and safety requirements in the latest revision of the GE Healthcare MR Service Safety Manual (5452735).
  • Have successfully completed all relevant GE Healthcare Environmental Health and Safety (EHS) courses (or for non-GE employees, equivalent workplace training courses).
  • Comply with all site-specific training and workplace safety requirements.

If you have any safety concerns at any time, do not begin work or immediately stop work and move to a safe location. Immediately contact your supervisor or site safety officer for instructions on how to proceed.

The document describes the replacement procedures for the major components of the original Gen1 CPC cabinet (5411744) and the new Gen2 cabinet (5750811). Because all of the major components are the same dimensions (depth and width), the replacement instructions are the same, with the exception of the top module of the original cabinet (5411744).

Figure 1. CPC cabinet (Gen1)

The major components of the original CPC cabinet (5411744) are:

  1. Combiner module: 5411744-8
  2. Power amplifier #1 and #2: 5411744-6
  3. Driver chassis: 5411744-7
  4. Power supply: 5411744-9
Figure 2. CPC cabinet (Gen2)

The major components of the new CPC cabinet (5750811) are:

  1. Power amplifier: 5750811-8
  2. Power supply: 5750811-7
Topic ID: id_SL12714125-1242409

Preparation

Procedure

  1. Perform LOTO on the RF amplifier before beginning this procedure. See MR Service Safety Manual, PN 5452735. See the section containing “LOTO for RF Amplifier” for instructions to properly perform LOTO on the MNS amplifier.
  2. Confirm that the hoist support brackets are installed.
    Figure 3. CPC Cabinet – Top with Hoist Support Brackets
    Item Description
    1Hoist support brackets
  3. Install the hoist. Use the instructions in Hoist Service Kit and Lifting Accessories to set up the hoist.

    Instead of the support tube (from the HEC cabinet) being attached to the top of the cabinet, the support tube is attached to the front hoist support bracket.

    Figure 4. Hoist Installed on CPC Cabinet
    Item Description
    1Hoist pulley and chain
    2Hoist safety pin
    3Main lifting beam from PDU/PGR
    4Support tube from HEC
    5MNS Hoist support bracket
  4. Remove all cables at the rear of the component being replaced.
  5. Remove all screws that secure the front of the component to the cabinet.
  6. Follow the instructions for the type of component you are replacing.
Topic ID: id_SL12714126-1242409

Replace Combiner

Procedure

  1. Slide the top component out until the guide rails are locked into place.
  2. With two engineers, release the slide rails on both sides of the combiner. Support the combiner during this process.
    Figure 5.
    Item Description
    1Slide cabinet rail back into the cabinet while supporting weight of combiner
  3. Attach the FRU replacement brackets to each side of the combiner module.

    Each bracket is held in place with three screws. Tighten each screw so that the bracket is securely fastened to the component.

    Figure 6. FRU Replacement Bracket on Component
  4. Attach the hoist hooks into the slots on each bracket.

    When removing the top module, there will be some slack in the hoist chain. Confirm that the chain links are aligned properly.

    Figure 7. Hoist Hooks Attached to Combiner Module
  5. Remove the module by having two FEs support both sides of the module, then slide the guide rail back into the cabinet.
    Figure 8. Removing Module from CPC Cabinet
    Item Description
    1Slide cabinet rail back into the cabinet while supporting weight of combiner
  6. On the opposite side, slide the other support rail back into the cabinet. The module is now entirely support by the hoist.
  7. Lower the combiner module onto the top section of the FRU crate.
    Figure 9. Top Section of FRU Packing Crate
  8. Remove the FRU replacements brackets from the old component and install them on the new component.
  9. Attach the component to the hoist.
  10. With two persons, raise the new module to the height of the slide rail. Attach the module to the guide rails.
  11. Slide the component back into the cabinet. Reinstall the fasteners into the front of the component so it is secure in the cabinet.
  12. Reattach the cables per cable label identifiers.
  13. Proceed to Finalization.
Topic ID: id_SL12714714-1242409

Replace Amplifier Component

About this task

The original CPC cabinet has four lower component (power amplifier #1 and #2, driver chassis, and power supply) that all have the same dimensions (depth and width). The replacement instructions for these components are the same. The new CPC cabinet has two lower components (power amplifier and power supply. They also have the same dimensions and same replacement instructions.

Procedure

  1. Remove all cables from the rear of the component.
  2. Remove fasteners from the front of the component.
  3. Slide the component out until the guide rails are locked into place.
  4. Attach the FRU replacement brackets to each side of the combiner module.

    Each bracket is held in place with three screws. Tighten each screw so that the bracket is securely fastened to the component.

    Figure 10. FRU Replacement Bracket on Component
  5. Attach the hoist hooks into the slots on each bracket. Install the spreader bar to the hoist to stabilize the chains. Confirm that the chain links are aligned properly.
    Figure 11. Spreader Bar Attached to Hoist
    Item Description
    1Hoist spreader bar
    2FRU replacement brackets
  6. Raise the component using the hoist to take the weight of the FRU off of the cabinet guide rails.
  7. Retract the guide rails from each side. Push in the button on the guide rail to unlock the rail and slide the rail back into the cabinet.

    The hoist is now supporting the component.

    Figure 12. Release Button on Guide Rail
    Item Description
    1Button on cabinet guide rail
  8. Lower the component onto the top section of the FRU crate. Move the defective component out of the way and move the new component into position.
    Figure 13. Top Section of FRU Packing Crate
  9. Remove the FRU replacement brackets from the old component and install them on the new component.
  10. Attach the hoist hooks to the slots in the FRU replacement brackets and raise the component so that the rail on the component is level with the rail in the cabinet.
  11. Slide the cabinet rails onto the component.
  12. When the component is secured to the guide rails, remove the hoist and the FRU replacement brackets.
  13. Slide the component into the cabinet and confirm that the guide rail is locked.
  14. Install the fasteners into the front of the cabinet.
  15. Install the cables
  16. Proceed to Finalization.