Endress+Hauser Deltabar PMD75B HART, Руководство пользователя

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Deltabar PMD75B HART Commissioning
Hauser 43
9.7.5 Outputting a unit via the operating tool (FieldCare), handheld,
AMS, PDM, etc.
Pressure and temperature units are converted automatically. Other units are not
converted.
In the following example, the volume in a tank should be measured in liters. The
maximum volume of1 000 l (264 gal) corresponds to a pressure of450 mbar (6.75 psi).
The minimum volume of 0 liters 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 position adjustment if necessary
50
p
[mbar]
450
–
+
+ -
V
[l]
1000
0
B
450 mbar
1000 l
A
50 mbar
0 l
A0039100
A "Pressure value" parameter and "Scaled variable value" parameter
B "Pressure value" parameter and "Scaled variable value" parameter
The pressure present is displayed in the operating tool on the same settings page in
the "Pressure" field.
1. Enter the pressure value for the lower calibration point via the Pressure value
parameter: 50 mbar (0.75 psi)
 Menu path: Application → Scaled Variable → Pressure value
2. Enter the volume value for the lower calibration point via the Scaled variable value
parameter: 0 l
 Menu path: Application → Scaled Variable → Scaled variable value
3. Enter the pressure value for the upper calibration point via the Pressure value
parameter: 450 mbar (6.75 psi)
 Menu path: Application → Scaled Variable → Pressure value
4. Enter the volume value for the upper calibration point via the Scaled variable value
parameter: 1 000 l (264 gal)
 Menu path: Application → Scaled Variable → Scaled variable value
Result: The measuring range is set for 0 to 1 000 l (0 to 264 gal).
Low flow cut off (square root extraction)
In the lower measuring range, small flow quantities (creepages) can lead to large
fluctuations in the measured value. This measured value fluctuation can be suppressed.