Endress+Hauser Cerabar M, Руководство по эксплуатации

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Cerabar M, Deltapilot M Commissioning
Hauser 53
Pos. zero adjust (007) (gauge pressure sensors)
Write permission Operator/Maintenance/Expert
Description Pos. zero adjustment – the pressure difference between zero (set point) and the measured
pressure need not be known.
Example • Measured value = 2.2 mbar (0.033 psi)
• You correct the measured value via the "Pos. zero adjust" parameter with the "Confirm"
option. This means that you are assigning the value 0.0 to the pressure present.
• Measured value (after pos. zero adjustment) = 0.0 mbar
• The current value is also corrected.
Selection • Confirm
• Cancel
Factory setting Cancel
8.5 Configuring level measurement
8.5.1 Information on level measurement
• The limit values are not checked, i.e. the values entered must suit the sensor and
measuring task for the device to be able to measure correctly.
• Customer-specific units are not possible.
• There is no unit conversion.
• The values entered for "Empty calib./Full calib.", "Empty pressure/Full pressure" and
"Set LRV/Set URV" must be at least 1% apart. The value will be rejected, and a mes-
sage displayed, if the values are too close together.
8.5.2 Overview of level measurement
Measuring task Level selec-
tion Measured variable options Description Measured value display
Calibration is performed by
entering two pressure-level
value pairs. "In pressure" Via the "Output unit" parame-
ter:
%, level, volume or mass
units. • Calibration with reference pressure (wet
calibration) →  53
• Calibration without reference pressure (dry
calibration) →  55
The measured value dis-
play shows the measured
value.
8.5.3 "In pressure" level selection: Calibration with reference
pressure (wet calibration)
Example:
In this example, the level in a tank should be measured in "m". The maximum level is
3 m (9.8 ft).
The pressure range is derived from the level and the density of the medium. In this case,
the device sets the pressure range to 0 to 300 mbar (0 to 4.5 psi).