Michell Instruments Liquidew EExd, User Manual

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Liquidew EExd User’s Manual
Michell Instruments 49
APPENDIX D
D.2 Calibration Software
A calibration correction utility has been integrated into the Process Application Software.
This allows authorized users to input calibration information in order to effect a real-
time correction of the displayed dew point. This software facilitates the uploading and
downloading of the instrument's calibration via the Modbus RTU interface.
The figure below shows the Calibration Correction window; two sets of data may be
entered:
• Ref DP Dew-point data for the reference hygrometer
(sometimes called the actual dew point or the
standard)
• Liquidew DP Measured dew-point value of the Liquidew
under test
Data can be entered for 13 calibration points b20 and -100°Cdp (+68 and
-148°Fdp). However, if no data is available then the
Ref DP
and
Liquidew DP
should
remain equal and be exact for the calibration point as shown in the figure below.
Cal point Ref Dp Liquidew Dp
Figure 31 Calibration Correction Data
NOTE: The figure above shows calibration data for -20 to –40°Cdp only. The
Ref Dp and Liquidew Dp are equal for points where no calibration data is
available.