Parameter Setup - Michell Instruments Optidew User Manual

OPERATION
3.4.4

Parameter Setup

The Parameter Setup window allows the setting and ranging of Channel 1 and 2 mA
outputs, the duration for DCC, HOLD, and
pressure and alarm set points.
The display units and Channel 1 mA output are selected by left clicking in the relevant
box. This will change the settings of both the instrument and the virtual hygrometer
window. Changing the mA outputs from 4-20 mA to 0-20 mA & vice versa will change
both Channel 1 & Channel 2 mA outputs.
The maximum and minimum values of Channel 1 and Channel 2 are –200 to +1000
respectively, allowing the range of the outputs to be anywhere between these limits.
The values for Max and Min must be whole numbers with a difference between them of
at least 1°C/F.
If Channel 1 is to be set for % RH, gm
of Channel 1 Min should be 0, as a negative value for these parameters is not possible.
The pressure value is used to correct gm
entering the atmospheric pressure the display and Channel 1 mA output (if either gm
or gkg is selected) will both be corrected accordingly.
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The Alarm can be set to OFF or set to be active on any of the process variables,
i.e. dew point, ambient temperature, temperature difference, % RH, gm
shown above. The set point needs to be an integer value between –200 and +1000,
although negative set points are only valid for dew point and ambient temperature. If
the process variable exceeds the set point, the alarm indicator on the virtual hygrometer
will illuminate and the Optics Fault/Alarm Relay will change state.
To change any of the values, enter the required value and click on the return key. The
background of the text box will change to yellow to indicate that the change is taking
place. When confi rmation has been received that the instrument has accepted the
change, the background will change back to green.
NOTE: When the Parameter Setup window is open, the values in the Virtual
Hygrometer window are frozen. The Parameter Setup window needs to be closed
for the software to resume normal display mode.
20
Optidew Series User's Manual
Measurement,
Parameter Setup Window
Figure 6
, gkg
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and gkg
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and the values for atmospheric
or ∆ (t – tdp), then the minimum value
for atmospheric pressure. By
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97430 Issue 2, March 2017
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or gkg as
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