OHAUS Explorer Balances, Руководство по обслуживанию

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APPENDIX B - SERVICE MENU
Explorer Series Service Manual 67 Ohaus Corporation www.ohaus.com
RAMP
The ramp display shows the percentage of use of the A to D circuit, that is, of the temperature-
compensated duty cycle. The actual value is not as important as how it changes. It should increase
as the weight on the balance is increased. The ramp display should remain constant without
fluctuations.
The normal range is within 3% to 97%. If the readings are outside this range the load-cell is likely
bad. Fluctuations in the display may indicate a mechanical interference, a cable connection
problem, a damaged Main PCB or a damaged load-cell.
3 Point- LINEARITY CALIBRATION
A three point linearization is also rarely required and is difficult to perform accurately under the less
than ideal conditions outside the factory. This service calibration requires that accurate calibration
weights be used. Calibration points are done at approximately 0, 50% and 100% of maximum
capacity. After the linearization procedure the balance will automatically start a Service Span
calibration and then a Service Internal Calibration.
The sequence of loading the test weights on the platform is very important to insure a correct
linearity calibration. Refer to the diagram below for the correct weight sequence.