Endress+Hauser Waterpilot FMX21, Руководство по эксплуатации

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Waterpilot FMX21 Commissioning
Hauser 51
10. The hydrostatic pressure for the upper calibration point is present at the device, here
300 mbar (4.35 psi) for example.Select the "Full calib." parameter. Enter the level
value, here 3 m (9.8 ft) for example. By confirming the value, you assign the pressure
value present to the upper level value.
 Menu path: Setup → Extended setup → Level → Full calib.
11. Use the "Set LRV" parameter to set the level value for the lower current value (4 mA),
here "0 m" for example.
 Menu path: Setup → Extended setup → Current output → Set LRV
12. Use the "Set URV" parameter to set the level value for the upper current value
(20 mA) (3 m (9.8 ft)).
 Menu path: Setup → Extended setup → Current output → Set URV
13. If the process uses a medium other than that on which the calibration was based, the
new density must be specified in the "Process density" parameter.
 Menu path: Setup → Extended setup → Level → Process density.
The process density can be changed only if automatic density correction is switched
off (see step 5).
The measuring range is configured for 0 to 3 m (0 to 9.8 ft).
For this level mode, the measured variables %, level, volume and mass are available,
see "Output unit" →  96.
9.9.5 "In height" level selection Calibration without reference
pressure (dry calibration)
Example:
In this example, the volume in a tank should be measured in liters. The maximum volume
of 1 000 l (264 gal)corresponds to a level of 4 m (13 ft). The minimum volume of 0 liters
corresponds to a level of 0 m since the process membrane of the probe is at the start of the
level measuring range.
Prerequisite:
• The measured variable is in direct proportion to the pressure.
• This is a theoretical calibration i.e. the height and volume values for the lower and upper
calibration point must be known.
• The values entered for "Empty calib./Full calib.", "Empty height/Full height" and" Set
LRV/Set URV" must be at least 1% apart. The value will be rejected, and a message
displayed, if the values are too close together. Other limit values are not checked,
i.e. the values entered must be appropriate for the sensor and the measuring task
for the device to be able to measure correctly.
• Due to the orientation of the device, there may be pressure shifts in the measured
value, i.e. when the vessel is empty or partly filled, the measured value is not zero.
For information on how to perform position adjustment, see →  43.