3 start calibration – COSA Xentaur Xentaur XDT User Manual

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XDT User’s Manual

tings; the ‘SET’ indicator means that changes can be made; the ‘HI’ indicator means that
we are changing the HI Alarm, (alarm #1).

Note that if the instrument does not have the alarm options installed this MODE (User Option)
will not appear.

4. Push the UP or DOWN buttons until the display shows:

the

-B

means energize below or de-energize above set dewpoint, the

means faults look

like high dewpoint. If the display shows LOC, the alarm changes are locked out, repeat step
1.

5. Push the MODE button. The display will show:

the ‘DEWPOINT’ indicator means that we are changing the alarm trigger dewpoint

6. Push the UP or DOWN buttons until the display shows:

7. Push the MODE button. The display will show:

the

indicates that we are changing the hysteresis of the alarm.

8. Push the UP or DOWN buttons until the display shows:

9. Push the MODE button until the instrument goes to the dewpoint display mode.
10. If it is desired to prevent inadvertent alarm settings changes by unauthorized people, acti-

vate the Lockout.

The Alarm Relays switch on non-pressure corrected dewpoints. Thus enabling or disabling the
pressure correction wil not effect the relays.

The instrument will retain the alarm settings even if the power is turned off.

3.4.4.3 Start Calibration

The instrument is calibrated at the factory with the sensor it is shipped with and does not need to
be re-calibrated prior to installation.
The calibration mode allows two different types of calibrations.
•

SpanCheck™: an Automatic Calibration using the sensor’s ability to saturate, thus no addi-
tional materials or equipment are required, this calibration is most useful after long periods of
usage and a suspicion of performance degradation.

•

Single point calibration: the calibration curve derived from SpanCheck is modified at a single
point using the output of the sensor as it is exposed to a gas with a known dewpoint. This cal-
ibration is most useful when the sensor is exposed to hygroscopic substances which constantly
alter the equilibrium between the sensor and the gas being measured (e.g. glycol), or when the
sensor is exposed to corrosive gasses and may drift. If the known gas is chosen to be at a dew-

SET
HI

˚C

DEWPOINT

SET
HI

****

˚C

DEWPOINT

SET
HI

˚C

SET
HI

˚C

SET
HI