Off-Center Load Adjustment For Block Style Models - OHAUS PA64 Service Manual

CHAPTER 4 TESTING

4.4.5 Off-Center Load Adjustment for Block Style Models

Do not attempt these adjustments unless the balance is free from drafts.
The balance is very sensitive and adjustments will be affected.
Adjust the Block Style Load Cell by removing
material from the locations indicated in Figure
4-7. Use a few strokes with a round needle
file exerting slight pressure.
Warning
–
Do not file at the edge at the flexible
bearing positions.
–
On completion of the adjustments, clean
the filing sites by removing the grindings
with adhesive tape (do not blow the
grindings away!).
1. Set Auto-Zero to Off, in Menu
Setup.
2. Open the balance. (See Section
3.1.)
3. Reinstall the Pan.
4. Plug the power cord into the
balance and turn it on.
5. Place a mass that weighs the
balance's full capacity on the center
of the Pan.
6. Press O/T (the center button) to
tare the balance and return the
displayed weight to 0g. Move the mass to the front, back, left and right edges of the
Pan. Note the displayed values.
7. Correct any error by filing at one or two of the marked positions. (See Figure 4-7.)
8. Adjust as shown until the tolerance is +/-5 counts.
9. Repeat Off-Center Load Test.
10. Turn the balance OFF.
11. Remove the Platform and re-assemble the balance. (See Section 3.3.11.)
12. Turn Auto-Zero back to On, in Menu Setup.
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NOTE:
If test weight
is unbalanced...
–
+
–
+
+
–
–
+
Figure 4-7. Using a Needle File to adjust Off
Center Load on Block Style Load Cells.
4-6 Pioneer™ Balances Service Manual
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...File in position(s)
marked:
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