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KAHN INSTRUMENTS, INC.
885 Wells Road, Wethersfield, CT 06109
Tel: 860-529-8643; Fax: 860-529-1895
E-mail: [email protected]
www.kahn.com
b)
The button may also be used to determine whether or not the instrument is
controlling at a dewpoint or is not able to reach it. This situation could arise
when attempting to measure very low dewpoints without using suitable
sensor cooling.
Momentary pressing of the MAX COOL button should cause a dip in the mirror
temperature which, upon release of the button, will provoke the mirror temperature into
oscillation around the dewpoint value. After a few minutes the mirror should return to its
original stable temperature. If this does not happen it may be necessary to consider
improving the method of sensor cooling.
2.12 Display Operation
There are two, six digit 7-segment LED displays on the front panel of the monitor unit.
These can be configured to display a number of measured and calculated parameters.
Note that all parameters listed in Section 4.5.1 and 4.5.2 are available on the analog and
RS232 outputs, regardless of which are displayed at any time.
During operation, if %RH is selected, the lower display will automatically display the
sample gas temperature. The display is configured such that two “calculated” parameters
cannot be displayed at any time.
Note that the operation of the display depends on whether the remote temperature probe
is connected. If the probe is not connected, remote temperature and %RH is not
displayed and °C/°F mode is selected by the upper “UNIT SELECT” push button.
2.12.1 Upper Display
When the instrument is initially switched ON, the measured dewpoint in degrees Celsius
(°C) is displayed on the upper display. The two digit annunciator, between the upper
“UNIT SELECT” push button and the upper display will display “C” indicating °Cdp.
If the remote temperature probe is connected, by pressing the upper “UNIT SELECT”
push button the upper display may be toggled between measured dewpoint (°C) and
Relative Humidity (%RH). The two digit annunciator, between the upper “UNIT SELECT”
push button and the upper display will display “rh” indicating %RH.
If the remote temperature probe is not connected, by pressing the upper “UNIT SELECT”
push button, the upper display may be toggled between measured dewpoint in °C and °F.
The two digit annunciator will display “F” indicating degrees Fahrenheit.
The “UNIT SELECT” switch will scroll through the functions as follows:
