Endress+Hauser Deltabar PMD75B HART, Руководство пользователя

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Deltabar PMD75B HART Commissioning
Hauser 41
9.7.3 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 measuring 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
• The pressure profile must be linear ( SV - Transfer function parameter = Linear option
Display: Under Guidance menu Commissioning wizard, keep pressing the  key until
the Assign PV parameter is reached. Press the  key to confirm. Select the scaled
variable and press the  key to confirm.
FieldCare: Guidance menu Commissioning wizard Press the Start option, then press
again until the SV and PV values can be configured.
• In the Assign PV parameter, the Pressure option must be set (factory setting)
Display: In the Guidance menu Commissioning wizard, keep pressing the  key until
the Assign PV parameter is reached. Confirm with the  key, select the Pressure option
and press the  key to confirm.
FieldCare: The PV value can also be modified in the Application menu Scaled variable
parameter.
B
450 mbar
20 mA
A
50 mbar
4 mA
I
[mA]
20
4
50
p
[mbar]
450
–
+
+ -
A0039093
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)).
 Menu path: Guidance → Commissioning → Lower range value output
2. Enter the pressure value for the 20 mA current via the Upper range value output
parameter (450 mbar (6.75 psi))
 Menu path: Guidance → Commissioning → Upper range value output
Result: The measuring range is set to 4 to 20 mA.