SIGNA MR355 / SIGNA MR360
Service Manual
5856356-3EN Revision 5.0
Basic Service Documentation. Copyright General Electric Company.
Object ID: 00000018WIA3091FF20GYZ
Topic ID: id_13106475 Version: 1.2
Date: Jul 5, 2019 11:49:11 PM

16CH RRx Replacement (Mobile Site)

Prerequisites

Table 1. Personnel requirements
Required persons	Preliminary requirements	Procedure	Finalization
1	Not Applicable	30 minutes	Not Applicable

Table 2. Tools and test equipment
Item	Quantity	Effectivity	Part number	Manufacturer
Non Magnetic Tool Set	1	-	-	-

Table 3. Replacement parts
Item	Quantity	Effectivity	Part number	Manufacturer
RRX (Refer to Illustrated Parts)	1	-	-	-

Table 4. Safety

DANGER

STRONG MAGNETIC FIELD!

FERROUS MATERIALS CAN BECOME DANGEROUS PROJECTILES IN THE PRESENCE OF THE MAGNETIC FIELD PRODUCED BY THE SIGNA MAGNET.

Do not Bring any ferromagnetic tools or equipment into the magnet room.

Warning

ELECTROCUTION HAZARD!

DANGEROUS VOLTAGES ARE PRESENT AROUND THE MAGNET SUBSYSTEM WHEN ENERGIZED.

LOCK AND TAG OUT POWER TO THE magnet room BEFORE STARTING WORK.

Notice

Electrostatic discharge (ESD) can cause permanent damage to electronic components.

Observe the following ESD precautions:

Wear a static wrist strap to ensure that any accumulated electrostatic charge is discharged from your body to the ground.

Create a common ground for the equipment being worked on by connecting the static-free mat, static wrist strap, and peripheral units to that piece of equipment.

Table 5. Required conditions
Condition	Reference	Effectivity
System Power must be turned OFF. Refer to System Cabinet PDU Main Breaker LOTO Procedure.	-	-

Procedure

Remove covers.
RRX is located on the wall.

Figure 1. RRX Location
Disconnect the bottom cables from J7, J5, J4, J8.

Note: Handle the Fibre Optic cables with care, they are very fragile.

Figure 2. RRX Cable Removal

CAUTION

RRx contains ferrous materials.

Do not bring it very close to magnet bore during replacement.

If it is very close to the magnet bore, it will be attracted to the bore with great force.

Loosen 4 screws.

Pull out a little and disconnect the top 2 cables from J1, J2.

Figure 3. Pull out a little and disconnect J1, J2
Restore it by the reverse order of the removal.

Finalization

Restore the Power. Refer to System Cabinet PDU Main Breaker LOTO Procedure.
Perform the following Diags and confirm that all of the tests are passed.
Perform System Gain Calibration.
Perform one Body or Head Scan.
Perform SPT Coherent Noise Test .
Note: Perform SPT Coherent Noise Test Only by selecting 'No' for 'Select All Tests?' and 'ON' for 'Coherent Noise'. No need to perform SPT Full test.