Endress+Hauser Waterpilot FMX21, Руководство по эксплуатации

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Commissioning Waterpilot FMX21
60 Hauser
1
2
3
4
FXN520
A0018763
1 HART master, PLC (programmable logic controller)
2 Multidrop Connector FXN520
3 TMT72 temperature head transmitter
4 Device
Device adjustment for level measurement
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. Perform level adjustment (wet or dry)
6. Via the "Bus address" parameter, set an address that is not equal to "0", e.g. the bus
address = 1. (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
The output current of the temperature head transmitter used must also be set to
"Fixed" and have a HART address other than zero (e.g. address = 2).
‣
Switch on the burst mode via the "Burst mode" parameter.
 Menu path: Expert → Communication → HART config
By balancing the pressure signal and temperature signal in a suitable HART master (e.g.
PLC), a corrected level value can be determined for any medium by using a suitable density
function.
9.10.3 Automatic density compensation using an external
temperature signal for calculation in the device
Example:
In this example, the device with an integrated Pt100 is connected to a HART-compliant
temperature transmitter via the common communication bus. With this option, the signal
of the Pt100 is evaluated with a HART-compliant temperature head transmitter (min.
HART 5.0) that supports the burst mode. The change in the water density caused by
changing temperatures is automatically factored into the level signal by activating the
automatic density compensation.