Siemens SITRANS P DS III Operating Instructions Manual page 111

In the calculation example, the two pairs of values 0%;0% and 100%;100% are configured
for the customized "characteristic curve". This is the default setting. The measured value
from the pressure scaling is transferred 1:1 in this example.
DV [x]
L
m
MA
ME
P
V
Figure 7-3
Configure the "Output scaling, volume" with a unit from the volume range and the measuring
limits for the device variable "Volume". The characteristic curve output directly affects the
volume scaling input.
In the calculation example, for the measuring limits from 0 and 100 l, a volume of 50 l is
yielded for process pressure of 1 bar.
The "Level" parameter setting also still automatically activates the device variable for the
mass. If you have not yet configured a value for the density, the initial value of 1 kg/l is
preset. In the calculation example for the "Mass" device variable, a mass of 250 kg is derived
at a density of 5 kg/l.
Note
When the density changes, the measuring range limits have to be adjusted accordingly.
You can configure all parameter settings for the "Level" block in SIMATIC PDM or the HART
communicator. Activate the "Level" measuring mode for this purpose. For all settings, the
measuring limits may be exceeded by +/-20%. Values which lie above or below that will be
rejected by the device.
SITRANS P DS III with HART
Operating Instructions, 06/2013, A5E00047092-09
Device variable x
Level
Mass
Start of scale value
Full scale value
Pressure
Volume
Functions of the "Level" block
Operating functions through HART
7.3 Selecting the measuring modes
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