Endress+Hauser Deltabar FMD72, Руководство по эксплуатации

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Commissioning Deltabar FMD72
58
11.9 Configuring pressure measurement
11.9.1 Calibration without reference pressure (dry calibration)
Example:
In this example, a device with a 400 mbar (6 psi) sensor module is configured for the 0 to +300
mbar (4.4 psi) measuring range, i.e. the 4 mA value and the 20 mA value are assigned 0 mbar and
300 mbar (4.4 psi) respectively.
Prerequisite:
This is a theoretical calibration, i.e. the pressure values for the lower and upper range are known.
It is not necessary to apply pressure.
Due to the orientation of the device, there may be pressure shifts in the measured value, i.e.
the measured value is not zero in a pressureless condition. For information on how to perform
position adjustment, see Pos. Zero Adjust(
®
ä 44) section.
Description
1 Select the "Level" measuring mode via the
"Measuring mode (005)" parameter.
Menu path: Setup
®
Measuring mode
20
4
I
[mA]
0 300
p
[mbar]
A0017671
1 See table, step 3.
2 See table, step 4.
2 Select a pressure engineering unit via the "Press Eng.
Unit (125)" parameter, here "mbar" for example.
Menu path: Setup
®
Press Eng. Unit
3 Select "Set LRV (013)" parameter.
Menu path: Setup
®
Set LRV
Enter and confirm the value (here 0 mbar (0 psi)) for
the "Set LRV" parameter. This pressure value is
assigned to the lower current value (4 mA).
4 Select the "Set URV (014)" parameter.
Menu path: Setup
®
Set URV
Enter and confirm the value (here 300 mbar (4.5
psi)) for the "Set URV (014)" parameter. This
pressure value is assigned to the upper current value
(20 mA).
5 Result:
The measuring range is configured for 0 to +300
mbar (4.5 psi).