ADVENTURER+ Service Manual P/N 83020790 A
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Note: The reference resistor of the Position Sensor PC Board must be transferred to the replacement
Position Sensor PC Board.
9. Install the replacement Sensor Board. Replace all screws previously removed. The Sensor Board contains
an optical sensor which must be positioned in the center of travel of the Ratio Beam when the balance is
operated. If the Sensor Board is positioned to low or to high, the balance will not function properly.
10. Resolder all wires previously removed.
11. Re-install the Transducer in the base assembly.
12. Connect the Transducer cable back to the Sensor Board.
13. Connect the Top Cover membrane switch cable to the Main PC Board. The Top Cover should be lying in
front of the Base not on top. If you are unable to connect the cable properly, see Figure 4-7 which is the
connector on the main PC board. You can operate the balance directly from the connector by momentarily
shorting out the pins as indicated to turn it on or off.
14. Place the Platform in place on top of the Transducer. Apply power to the balance and turn the balance on.
15. If the Sensor Board is improperly positioned, too high or too low, the display indicates Error 8.4. Adjust the
Sensor Board up and down until the display indicates other than 8.4. Then tighten the two screws. After
completing this adjustment, turn the balance off and remove the Platform.
16. Replace the Transducer Shield over the Transducer and secure with four screws.
17. Refer to paragraph 4.3.2, page 4-11 and re-assemble the balance.
18. Conduct Performance Tests.
4.4.4 Main Printed Circuit Board (PCB) Replacement - Precision and Analytical Balances
Refer to Figure 4-5 and 5-1 for this procedure.
1. Refer to paragraph 4.3.1, page 4-10 and open the balance.
2. On the Main PC Board, disconnect the Load Cell Cable, RS232 Cable, Power Cable and the cable from the
Membrane Switch on the front panel.
3. Remove the four screws on the Main PC Board which secure it to the Base.
4. Install replacement Main PC Board in the reverse order as removed. Check the LCD display on the new
board and remove protective plastic covering if in place.
5. Refer to paragraph 4.3.2, page 4-11 and re-assemble the balance.
6. After assembly, verify that the balance meets all specifications. Perform all tests.
4.4.5 RS232 Printed Circuit Board Replacement - Precision and Analytical Balances
The RS232 PC Board is located at the rear of the balance. Refer to Figure 4-5 and Figure 6-5 for this procedure.
1. Refer to paragraph 4.3.1, page 4-10 and open the balance.
2. At the rear of the balance, remove the two hex head nuts which secure the RS232 Board to the base.
3. Remove the small mounting plate and lift out the RS232 board.
4. Disconnect the RS232 Cable from the RS232 PC Board.
5. Install replacement RS232 Board in the reverse order as removed.
6. Refer to paragraph 4.3.2, page 4-11 and re-assemble the balance.
7. After assembly, verify that the balance meets all specifications. Perform all tests.
4.4.6 Membrane Switch Replacement - Precision and Analytical Balances
The Membrane Switch is mounted on the Top Cover. The replacement Membrane Switch is supplied with a peel
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