Keysight N5224B, Руководство по обслуживанию

Страница: 531 / 614

Keysight N5224B/25B Service Guide 7-25
Repair and Replacement Procedures
Removing and Replacing the A19 Midplane Board
Removing and Replacing the A19 Midplane Board
Tools Required
— T-10 TORX driver (torque to 9 in-lb)
— T-20 TORX driver (torque to 21 in-lb)
— 5/16 inch open-end torque wrench (torque to 10 in-lb)
— ESD grounding wrist strap
Removal Procedure
Refer to Figure 7-12 for this procedure.
1. Disconnect the power cord.
2. Remove the outer and inner covers. Refer to “Removing the Covers” on
page 7-7 .
3. Remove the A20 power supply assembly. Refer to “Removing and
Replacing the A20 Power Supply Assembly” on page 7-27 .
4. Remove the A21 CPU board assembly. Refer to “Removing and Replacing
the A21 CPU Board Assembly” on page 7-29 .
5. Remove six screws (item

) from the A19 midplane board.
6. Lift the board ejectors (item

) to the upright position to disengage the
A19 midplane board from the A18 system motherboard.
7. Note the positions of the six rubber grommets (item

) on the bottom
three A19 midplane board alignment pins. Remove these rubber
grommets and retain them for reinstallation on the new A19 midplane
board.
8. Lift the A19 midplane board out of the analyzer.
Replacement Procedure
1. Reverse the order of the removal procedure.
Be careful to align the guide pins on the A19 midplane board connectors
with the slots on the A18 system motherboard connectors.
The board ejectors should be in the upright position when installing the
A19 midplane board. Align these ejectors with the slots in the chassis
inner panels as the board is lowered into position and then push them
down flat.
Remember to install the six rubber grommets on the bottom three
alignment pins.
2. Perform the post-repair adjustments, verifications, and performance tests
that pertain to this removal procedure. Refer to Table 7-2 on page 7-78 .