Endress+Hauser Deltabar PMD78B, Руководство по эксплуатации

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Commissioning Deltabar PMD78B HART
52 Hauser
Example: Outputting of the pressure value at the current output
Pressure and temperature units are converted automatically. Other units are not
converted.
In the following example, the pressure value should be measured in a tank and output on
the current output. The maximum pressure of 450 mbar (6.75 psi) corresponds to the 20
mA current. The 4 mA current corresponds to a pressure of 50 mbar (0.75 psi).
Prerequisites:
• Measured variable in direct proportion to the pressure
• Due to the orientation of the device, there may be pressure shifts in the measured value
(when the vessel is empty or partly filled, the measured value is not zero)
Perform a position adjustment if necessary
• In the Assign PV parameter, the Pressure option must be selected (factory setting)
Display: In the Guidance menu Commissioning wizard, keep pressing the  key until
you reach the Assign PV parameter. Press the  key to confirm, select the Pressure
option and press  to confirm.
–
+
+ -
B
450 mbar
20 mA
A
50 mbar
4 mA
I
[mA]
20
4
50
p
[mbar]
450
A0039098
A Lower range value output
B Upper range value output
Adjustment:
1. Enter the pressure value for the 4 mA current via the Lower range value output
parameter (50 mbar (0.75 psi)).
2. Enter the pressure value for the 20 mA current via the Upper range value output
parameter (450 mbar (6.75 psi))
Result: The measuring range is set to 4 to 20 mA.