Servomex DF-130E, Руководство оператора

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Maintenance and Calibration Checks DF-150E 49
NOTE
The action of throwing the View Ref toggle switch to the Span
position freezes the present O2 value at the analog outputs. For 10
seconds after the toggle switch is released the analog outputs and
oxygen display are held at the last valid O2 value. Throwing the
View Ref toggle switch again during the 10 second delay will
display a meaningless number.
10.2.1.2 B. Adjust Span/Zero Calibration
1. Apply a calibrated span or zero gas to the analyzer.
2. Allow ample time for the analyzer to equilibrate.
3. If necessary, slowly turn the appropriate Span or Zero adjustment to obtain
an oxygen reading that agrees with the Span or Zero calibration gas.
4. Record the reference values as described above.
5. Allow 10 seconds for the analyzer to return to normal operation.
Figure 28: Calibration Controls
NOTE
The drift of the zero-baseline is small compared to the accuracy of
the instrument. As a result, for most applications, it is unnecessary
to adjust the zero set point of the analyzer.
10.2.2 Adjusting Calibration (with the Gas Scale
Factor Option installed)
For analyzers that have Scale Factor installed, the Span calibration
potentiometer is located to the right of the Sensor Off switch.