Analytical Industries GPR-1600 Series Trace PPB Oxygen Analyzer - Manual (Page 36)

Advanced Instruments Inc.
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Menu Functions – Zero Calibration
Factory Default Zero: The system eliminates any previous zero calibration offset adjustment stored in
memory and displays the unadjusted oxygen reading of the gas currently flowing
through the analyzer.
This function is recommended before performing a manual ZERO CALIBRATION or
when troubleshooting an analyzer. This function is not recommended for subsequent
periodic SPAN CALIBRATION - see Analysis Level Required above.
Auto Zero: Applicable only to analyzers equipped with an optional automated sample system. The
system automatically closes the sample inlet valve and opens the zero inlet valve at a
predetermined interval in time, see System Menu section above. It also trends the
downward slope of the oxygen reading. When the slope of the oxygen reading trend
approaches the factory set value, the system initiates a ZERO CALIBRATION offset
adjustment and displays an oxygen reading of 0.000 or 00.00 ppm.
Manual Zero: Recommended for optimum accuracy. The user must ascertain that the oxygen reading
has reached a stable value, see Zero Calibration Offset Adjustment Capability above,
below 50% of the most sensitive or lowest range available on the analyzer before the
system will accept and make a ZERO CALIBRATION offset adjustment.
If the user attempts to initiate the ZERO CALIBRATION function while the oxygen
reading is above 50% of the most sensitive or lowest range, the system displays the
message “CALIBRATION FAILED” and returns to the “Sample” mode.
Timed Zero Cal: Subtitle only, this function represented by the following menu options are applicable
only to analyzers equipped with an optional automated sample system.
Timed Zero Cal in ___ days:
Requires the user to enter a “number” representing the interval in days before the next
ZERO CALIBRATION.
Calibration will occur at ____:
Requires the user to enter a “military time in hours and minutes” representing the time
of day at which the next ZERO CALIBRATION will be initiated.
Menu Functions – Span Calibration
Factory Default Span: The system eliminates any previous span calibration adjustment stored in memory and
displays an oxygen reading +50% of the span gas value currently flowing through the
analyzer.
If the oxygen reading is outside +50% of the span gas value, the system displays the
message “CALIBRATION FAILED” and returns to the “Sample” mode. This feature
allows the user to test the sensor’s signal output without removing it from the sensor
housing.
This function is recommended before performing a SPAN CALIBRATION or when
troubleshooting an analyzer.
Span Gas Units/Value:
After initiating either Auto or Manual Span from the SPAN CALIBRATION menu, the
system produces a display prompting the user to select span gas in ppb, ppm or %
units, which is followed by a second display prompting the user to enter a numerical
span gas value.