Hach sc200, User Manual

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25% Oxygen Ultima/Ultima X Series Gas Monitor
For the SPAN function, ambient air is generally adequate for the
25% oxygen Ultima/Ultima X Series Gas Monitor as the expected
default span value is 20.8%. Therefore, when the display prompts
"APPLY SPAN GAS" it would be adequate to simply allow the
countdown to occur without applying gas.
NOTE: If the sensor is located in an area of normally low or enriched
oxygen, then a 20.8% oxygen sample must be applied when
the display prompts:
"APPLY SPAN GAS" .
XIR Calibration
Although a full calibration (zero and span) can be performed on the
Ultima XIR Gas Monitor, a no-gas calibration is sufficient to properly
calibrate the monitor. A zero adjustment is all that is required for a full
calibration. Normally, any degradation of the sensor’s performance is
associated with slight drifts in its zero response which, in turn, will
adversely affect its span performance. Restoring the sensor’s zero is
typically sufficient to restore its span performance.
A zero adjustment is performed by pressing the ZERO button on the
Calibrator or Controller and following the "Zeroing" instructions given
earlier in this chapter. After completing the zeroing function, perform a
span check to ensure proper operation. If the span check is
unsuccessful, perform a full calibration.
NOTE: For calibration of an XIR sensor operating with a Flow Cap,
temporarily replace the Flow Cap with the Environmental
Guard (packaged with the instrument) and perform the
following procedure.
The Calibration Cap must be removed from the XIR
environmental guard after completing the Zeroing and/or
Spanning procedure; otherwise, the sensor cannot
perform properly.
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WARNING
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