OHAUS MB25, Руководство по обслуживанию

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CHAPTER 3 MAINTENANCE PROCEDURES
Ohaus Corporation www.ohaus.com 3-6 MB23 and MB25 Service Manual
3.6 REPLACING THE MAIN PC BOARD
1. Open the Housing as explained in
Section 3.2.
2. Disconnect the Load Cell cable from
the Main PCB before lifting off the Load
Cell Cover.
3. Remove the four screws on the Load
Cell Cover. The two in the Power PCB
are machine screws. The two in the
Main PCB are self tapping screws.
(Note difference for re-assembly.)
4. Lift off the Load Cell Cover.
Figure 3-11. Load Cell Cover.
5. Disconnect power cable from the Main
PCB.
6. Remove two remaining screws that
secure Main PCB to Bottom Housing.
7. Lift out the Main PCB.
8. Install the replacement Main PCB.
9. Reassemble the Moisture Analyzer.
10. Calibrate the Moisture Analyzer.
(See Appendix A.) Perform all tests.
(See Chapter 4.) Figure 3-12. Main Printed Circuit Board.
3.6.1 Replacing the Display LCD
1. Follow steps 1
– 6 in Section 3.7.
2. Note location of backlight cables,
then remove them.
3. Cut the leads from the old LCD;
remove the old LCD.
4. Remove the remaining lead wires;
clean solder from the holes.
5. Install new backlight LCD. Position
backlight cables like originals, and
Figure 3-13. Display LCD on Main PCB.
solder in place.
6. Soldier in the LCD leads.