Discovery MR750w and SIGNA™ Architect T 3.0T System Service Methods
5690002-2EN Revision 4
Object ID: 00000018WIA30EBF030GYZ
Topic ID: id_12374937 Version: 1.2
Date: Jul 5, 2019 10:03:32 PM

MNS Upconverter Replacement

Prerequisites

Table 1. Personnel requirements
Required persons	Preliminary requirements	Procedure	Finalization
1	5 minutes	30 minutes	10 minutes

Table 2. Tools and test equipment
Item	Quantity	Effectivity	Part number	Manufacturer
Non-Magnetic Tool Kit	1	-	5112581	-

Table 3. Replacement parts
Item	Quantity	Effectivity	Part number	Manufacturer
MNS Upconverter Module	1	-	5189655-2	-

Procedure

Perform LOTO on the PEN cabinet. See the MR Service Safety Manual, PN 5452735.
Remove both of the rear pedestal side covers.
Locate the upconverter box, mounted on the front of the reroute box in the rear pedestal.

Figure 1. Upconverter Box

CAUTION

Some cables are ferrous and are attracted to the magnet.

Disconnect and connect cables carefully.

When disconnecting cables, ensure ends do not become attached to the magnet.

Disconnect cable connections from the upconverter box (viewing from front of the rear pedestal).

Remove the upconverter box from the rear pedestal and carefully move it away from the magnet.

Note:
Place upconverter box outside of magnet room before completing replacement procedure.
Mount the new upconverter box. For ease of installation in a confined space, follow these suggestions:
1. Attach one mounting bracket to the reroute box and the other mounting bracket directly to the MNS upconverter.
2. Approach the opposite side of the rear pedestal from where the mounting was attached and slide in the MNS upconverter. Fully attach the MNS upconverter to the reroute box.

Reconnect cables to the upconverter. See Figure 2 and Table 4 for cable connections.

Note:

On the RF control board, some cables may need to be disconnected in order to properly connect the MNS upconverter cables. Reconnect these cables after the upconverter is fully installed.

Table 4. MNS Upconverter Cable Connections
Cable Run Number	J# on MNS Upconverter	Connects to	Description
M1308	J3	J31 of Pen cabinet wall	MNS LO
M1309	J1	J33 of Pen cabinet wall	MNS loopback
M3356	J2	J11 - Slot 11 board of RF hub	Power and controls for MNS upconverter
[None]	J4	LPCA connector A	8W8 Rx signal input from connector A
[None]	J5	J8 of reroute box	8W8 upconverter signal output

Replace the rear pedestal side covers.

Notice

After LOTO is removed from the PEN cabinet, the Exciter board requires 20 minutes of power-up time before scanning.

Remove LOTO. See the MR Service Safety Manual, PN 5452735.

Finalization

Perform MNS Functional Checks.