CHAPTER 4 TESTINGOhaus Corporation www.ohaus.com 4-6 Pioneer™ Balances Service Manual4.4.5 Off-Center Load Adjustment for Block Style ModelsNOTE: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 removingmaterial from the locations indicated in Figure4-7. Use a few strokes with a round needlefile exerting slight pressure.Warning– Do not file at the edge at the flexiblebearing positions.– On completion of the adjustments, cleanthe filing sites by removing the grindingswith adhesive tape (do not blow thegrindings away!).1. Set Auto-Zero to Off, in MenuSetup.2. Open the balance. (See Section3.1.)3. Reinstall the Pan.4. Plug the power cord into thebalance and turn it on.5. Place a mass that weighs thebalance’s full capacity on the centerof the Pan.6. Press O/T (the center button) totare the balance and return the++++ÆÆÆÆIf test weightis unbalanced...ÆÆ ÆÆ––––...File in position(s)marked:Figure 4-7. Using a Needle File to adjust OffCenter Load on Block Style Load Cells.displayed weight to 0g. Move the mass to the front, back, left and right edges of thePan. 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.
