Appendix B. Service Menu - OHAUS NV212 Service Manual

APPENDIX B THE SERVICE MENU

APPENDIX B. SERVICE MENU

This section describes the Service Menu and sub-menus, which allow authorized service personnel to
perform factory Linearity and Span calibrations (no pre-set limits).
B.1 ENTERING THE SERVICE MENU
Turn the scale off.
Enter the Service Menu by pressing and holding
Zero/On and Tare together until rAmMP appears. This
will take approximately 8 seconds.
Press Yes to select Ramp.
B.2 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 scale is increased. The ramp display should remain constant without
fluctuations.
If you press Yes to select Ramp, a number appears. It
should be constant. Add masses from minimum to
maximum capacity. The reading will increase, but
should not fluctuate. The example at right is with no
weight on the Pan. It will vary with other scales.
To exit the ramp function, press Yes.
The scale advances to the Linear calibration menu.
Press Yes to perform Linear Calibration.
B.3 LINEAR CALIBRATION
Linear calibration automatically follows Ramp. To start from the Service Menu, press and hold
Zero/On and Tare together. As the scale powers up, RAMP appears. Press No to bypass Ramp.
Service Linearity does not have limit ranges on the weights used as does the standard user linearity
procedure.
Note:
Be careful not to touch the scale or the table while calibration is in progress, as it will cause
the process to fail.
When LIN appears, press Yes.
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Navigator Series Service Manual