Det-Tronics PIRECL Infrared Carbon Dioxide Gas Detector PointWatch Eclipse - Manual (Page 21)

19 95-8676 2.1
cAlibrAtion
CalIbraTIon oVerVIeW
Although routine calibration of the PointWatch Eclipse is
normally not required, the device supports non-intrusive
field calibration capability. Two (2) calibration procedure
options are provided:
1. normal Calibration is a two-step process consisting
of applying nitrogen and mid-scale (span)
adjustment. Calibration gas must be applied by
the operator to enable span adjustment. Prior to
calibration initiation, purge the Eclipse optics with
nitrogen to ensure that an accurate zero condition is
present.
For normal calibration, the recommended calibration
gas concentration is 1%/vol (10,000 ppm).
2. zero only Calibration is a one-step process
consisting of nitrogen (zero) condition adjustment
only, which is performed automatically by the device.
This procedure adjusts the zero signal output only,
and is normally used if the 4 milliampere signal level
has drifted. The cause of drift is typically due to
the presence of background gas during calibration.
Purge the Eclipse optics with pure nitrogen prior
to calibration initiation to ensure an accurate zero
condition is present.
aDDITIonal CalIbraTIon noTeS
Important
Always ensure that the correct gas type is used for
calibration. (2.5 LPM flow rate is recommended.)
NoTe
ensure that the detector has been operating for at
least two hours before calibrating.
NoTe
Always ensure that the eclipse is zero calibrated
with nitrogen.
NoTe
Under very windy conditions, it may not be
possible to successfully calibrate the eclipse. This
situation is easily corrected by using the eclipse
Calibration Bag (P/N 006672-002), available from
Det-Tronics.
NoTe
Always place the protective cap back on
the calibration nozzle after completion of span
calibration.