Michell Instruments XZR-400-BM, Руководство пользователя

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XZR400 Series User’s Manual
Michell Instruments 51
OPERATION
3.6.5 Total Pressure Correction (Optional)
This optional screen is used to adjust the low scale and the high scale of the external
pressure sensor, which is connected to D-Sub DA15 for all versions, except for the
XZR400A1 model, where the connection is carried out on the 8 pins connector. This
sensor compensates the total pressure in the MSRS cell.
When the gas pressure at the analyzer output is greater than the atmospheric pressure
sensor's upper limit (1,200 mbar), the total pressure adjustment is needed to guarantee
optimum operation of the analyzer.
The input signal from the external pressure sensor is a 4-20 mA analog signal representing
the output pressure of the analyzer. The signal enters the analyzer at terminals 11 and
12 of the D-Sub DA15 connector for all versions, except for the XZR400A1 model, where
the connection is carried out on pins 12 and 13 of the screw terminal.
Defective wiring/electrical supply of the total pressure sensor, or no connection of the
total pressure sensor’s 4-20 mA signal to the analyzer, generates a general fault alarm
and the display of a pressure fault message. This is not run if the sensor outputs a 0-5
V signal type.
In case of a pressure fault, the O
2
concentration will be displayed taking in account an
atmospheric pressure of 1000mbar. If the pressure of the measured gas is not within a
1000mbar ±20mbar bracket, the O
2
concentration on the display will be off the relative
2% tolerance.
Pressure Correction Screen
• Touch the area to select it and change it.
• Enter any new numeric value on the virtual keypad.
• Click
OK
to con fi rm or
Cancel
to discard the changes.
Pressure correction
5.6
Start of scale
End of scale
0.0 bar abs
2.0 bar abs
Figure 41
Pressure Correction Screen
Area Function
Start of scale
Touch the area to enter the low scale pressure value of the external
sensor.
End of scale
Touch the area to enter the high scale pressure value of the external
sensor.
Returns to the Main Menu Screen.