COSA Xentaur Xentaur LPDT - Manual (Page 30)

Section 3: Instrument
page 23
calibration procedure.
7. Install the sensor in the sample cell or adapter fitting or
put it back into the packaging container for later use.
The instrument will retain the calibration even if the power
is turned off.
Under certain conditions, an over (super) saturated sensor
may need to be completely dried out before a calibration is
performed. Symptoms of these conditions are a sensor that
will not go through the SpanCheck™ function to the
(1'
display, or a sensor that will not dry down after calibration.
To dry, install sensor in either a known dry gas stream i.e.
instrument quality air or dry nitrogen, or place sensor in a
dry can or bottle of desiccant and seal the container from
outside air (the shipping container is designed for this pur-
pose). After a minimum dry out period of 24 hours, proceed
with the calibration procedure of your choice.
SpanCheck™ calibrates sensors by using micro climates.
Please contact your representative if you have any questions
about how to create such micro climates.
A perfectly acceptable and accurate for calibration micro-
climate may be created for the XTR100 and XTR65 sensors
by cupping the sensor in the palm of one’s hand during the
SpanCheck™ procedure. Remember that the micro-climate
does not have to be accurate, it just has to be higher than the
designed saturation level. The dewpoint of the micro-cli-
mate within the fingers is usually higher than the dewpoint
of the room air and probably well above the +20°C upper
range of the sensor. On a dry day one may need to exhale in
the hand before cupping the sensor to guarantee a high dew-
point. The sensor should be warmed up close to body tem-
perature before performing this procedure. Care must be