OHAUS EC SERIES Service Manual

Also see for EC Series: Instruction manual Instruction manual

Contents

OHAUS EC SERIES Service Manual Manual pdf 25 page image

3-11CHAPTER 3 SCALE TESTING AND CALIBRATION3.6.4 Linearity TestThe linearity test is used to determine the linearity of the scale throughout its operating range. The resultsshould be in accordance with the specifications shown above. The reference mass should be approxi-mately 1/8 of the full-capacity of the scale.NOTE::::: The scale must pass the Off-Center Load test and Repeatability Test before the Linearity Test isperformed.BE CERTAIN TO USE THE SAME REFERENCE MASS THROUGHOUT THE LINEARITY TEST.1. Press ZERO to zero the display.2. Place the reference mass on the center of the platform and record the exact value (all decimalplaces) displayed.3. Remove the reference mass and verify that the display returns to zero. If it does not, disregard thereading, press ZERO to rezero the display, and take the reading again.4. Place a mass equal to 1/4 of the full scale capacity on the platform and press ZERO.5. Add the reference mass to the center of the platform and record the exact value displayed.6. Remove the reference mass and verify that the display returns to zero. If it does not, disregard thereading, press ZERO to rezero the display, and take the reading again.7. Place a mass equal to 1/2 of the full-scale capacity on the platform and press ZERO.8. Add the reference mass to the center of the platform and record the exact value displayed.9. Remove the reference mass and verify that the display returns to zero. If it does not, disregard thereading, press ZERO to rezero the display, and take the reading again.10. Place a mass equal to 3/4 of the full scale capacity on the platform and press ZERO.11. Add the reference mass to the center of the platform and record the exact value displayed.12 Remove the reference mass and verify that the display returns to zero. If it does not, disregard thereading, press ZERO to rezero the display, and take the reading again.13. Calculate the weight differences between the reading as shown in the recorded readings.14. The Maximum difference should be less than or equal to the Linearity specification for thescale.