Bar Graph; Sensor Calibration; Sensor Trim - Siemens SITRANS P DS III Operating Instructions Manual

7.15

Bar graph

Description
You can use this to switch on the "Bar graph" function in the device display as an alternative
to the unit display. The "Bar graph" function is disabled in the factory state.
See also
Display elements (Page 71)
7.16

Sensor calibration

7.16.1

Sensor trim

Description
The sensor trim can be used to set the characteristic curve of the transmitter at two sensor
trim points. The results are then correct measured values at the sensor trim points. The
sensor trim points can be selected as any points within the nominal range.
Devices that are not turned down prior to delivery are trimmed at 0 bar and the upper limit of
the nominal range; devices that are turned down prior to delivery are trimmed at the lower
and upper limits of the set pressure measuring range.
Application examples
● For a particular device that is not turned down (e.g. 63 bar), the typical measured value is
● A 63-bar transmitter is turned down to 4 to 7 bar. You can attain the highest possible
● A 250-mbar absolute pressure transmitter shows 25 mbar at 20 mbar (abs). A reference
SITRANS P DS III with HART
Operating Instructions, 06/2013, A5E00047092-09
50 bar. To attain the highest possible accuracy for this value, set the upper sensor
calibration at 50 bar.
accuracy by selecting 4 bar for the lower sensor calibration point and 7 bar for the upper.
pressure of 100 mbar is available. You can carry out zero point correction by performing
a lower sensor trim at 100 mbar.
Note
The accuracy of the test device should be at least three times as high as that of the
transmitter.
Operating functions through HART
7.15 Bar graph
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