Kahn Optisure Remote, User Manual

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Optisure Remote User’s Manual
Kahn Instruments 29
OPERATION
4.4 First Time Operation
Before using the instrument, please read through the Installation, Operation and
Maintenance sections of this manual. This instruction assumes that all recommendations
within these sections have been followed, and that the control unit and sensors are
physically installed and all electrical connections complete.
1. Insure that all sample connections are in good condition, of appropriate
materials and are leak-tight
2. Clean the mirror according to the instructions in section 4.8
3. Control the flow rate to within 0.1 to 2Nl/min (1l/min optimal)
4. Power on the instrument
4.5 Operational Functions
4.5.1 DCC Function
Dynamic Contamination Control (DCC) is a system designed to compensate for the loss
of measurement accuracy which results from mirror surface contamination.
During the DCC process the mirror is heated to a default temperature of 20°C above the
dew point to remove the condensation which has formed during measurement.
The surface finish of this mirror, with the contamination which remains, is used by
the optics as a reference point for further measurements. This removes the effect of
contamination on accuracy.
After switch-on, the mirror is assumed to be clean, therefore the instrument will only
run a DCC for 2 minutes to quickly establish a clean mirror reference point. By default,
every subsequent DCC is 4 minutes in duration and will automatically occur every 4
hours.
At certain times it may be desirable to disable the DCC function in order to prevent it
from interrupting a measurement cycle, e.g. during a calibration run. This is achieved
by setting 'Interval' to '0' in the DCC menu. See section 3.2.1 for further details.
A manual DCC can be initiated or cancelled by touching the DCC button on the Main
Screen. The DCC button is context sensitive, i.e. if DCC is on, the Main Screen shows
DCC OFF as being selectable. Similarly if DCC is off, DCC ON is shown.
It is possible to change the parameters relating to the DCC cycle on the DCC Setup
Screen, refer to Section 3.2.1
4.5.2 MAXCOOL Function
The MAXCOOL function over-rides the dew-point control loop and applies maximum
cooling drive to the Peltier heat pump. It can be used to determine:
• What temperature the mirror can be driven down to with reference to the
sensor body.
• Whether or not the instrument is controlling at the dew point and whether it
is able to reach it. This situation could, for instance, arise when attempting
to measure very low dew points where, possibly due to a high ambient
temperature, the Peltier heat pump is unable to depress the temperature
far enough to reach the dew point.