Endress+Hauser Waterpilot FMX21, Руководство по эксплуатации

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Commissioning Waterpilot FMX21
58 Hauser
Sensor level adjustment (Cerabar)
1. Select the "Level" measuring mode via the "Measuring mode" parameter.
 Menu path: Setup → Measuring mode
L
WARNING
Changing the measuring mode affects the span (URV)
This situation can result in product overflow.
‣
If the measuring mode is changed, the setting for the span (URV) must be checked in
the "Setup" operating menu and readjusted if necessary.
2. Select a pressure unit via the "Press. eng. unit" parameter, here "mbar" for example.
 Menu path: Setup → Press. eng. unit
3. The sensor is unpressurized, perform a position adjustment →  43
4. Set the output current to "Fixed" 4 mA via the "Current mode" parameter.
 Menu path: Expert → Communication → HART config
5. Via the "Bus address" parameter, set an address that is not equal to "0", e.g. the bus
address = 2. (HART 5.0 master: range 0 to 15, where address = "0" calls up the
"Signaling" setting; HART 6.0 master: range 0 to 63)
 Menu path: Expert → Communication → HART config
6. Activate the reading of a value sent externally in burst mode via the "Electr. Delta P"
parameter.
 Menu path: Expert → Application
7. Perform level adjustment (wet or dry)
Result: The measured value output by the atmospheric pressure sensor equals the level in
the deep well (differential signal) and can be read out by means of a HART request for the
address of the atmospheric pressure sensor.
• It is not permissible to reverse the assignment of the measuring points to the direction of
communication.
• The measured value of the transmitting device (via burst) must always be greater than
the measured value of the receiving device (via "Electr. Delta P" mode).
• Adjustments that involve an offset in the pressure values (e.g. position adjustment, trim)
must always suit the individual sensor and the sensor's orientation irrespective of the
"Electr. Delta P" application.
• Other settings result in non-permitted use of the "Electr. Delta P" mode and can lead to
incorrect measured values.
9.10 Automatic density compensation
9.10.1 Automatic density compensation with the internally measured
sensor temperature
Example:
In this example, the device is used for level measurement in water. The change in the
water density caused by changing temperatures is automatically factored into the level
signal by activating the automatic density compensation.