CHAPTER 3 MAINTENANCE PROCEDURES
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Adventurer ™ Balances Service Manual
3.6.2 Position Sensor Board Removal/Replacement/Adjustment
– Precision
If the Position Sensor Board is defective and requires replacement, proceed as follows:
1. Open the balance, and remove the Load Cell.
2. Un-solder the wires that attach
to the Position Sensor Board.
The 3-wire Ribbon Cable is
connected to the Contact
Board. The two white wires at
the top are thermistor wires:
polarity is not important. The
two wires at the bottom-right
must be placed back in their
original position. (See Figure
3-33.)
Figure 3-59. Position Sensor Board.
3. Remove the three screws holding the Position Sensor Board in place.
(The two on the right have washers. The one on the left doesn’t.)
4. Remove the Position Sensor Board, and install the replacement. Insert all screws
previously removed. Tighten the screws finger-tight to allow adjustment in Step 9.
5. Re-solder all wires. (See Figure 3-33.)
6. Place the Load Cell in position and mount it with one screw.
7. Connect the cable from the Main PCB to the Position Sensor Board.
8. Install 30111772/30111773 LCD 4.3 to the main PCBA as shown below.
Figure 3-60 4.3 LCD attached.
9. Operate the balance with the Weighing Pan in its normal position, but with the top cover
off. Power on using the middle button on the PCB.
NOTE:
The Position Sensor Board contains an Optical Sensor which must be positioned in the
Ratio Beam’s center of travel for the balance to function properly.
3-wire Ribbon
Cable
White, Red
Thermistor
cables
