VEGA VEGABAR 44 Profibus PA - Manual (Page 4)

4 VEGABAR 44 (Profibus PA)
Product description
1 Product description
1.1 Function and configuration
VEGABAR 44 process pressure transmitters
are efficient instruments for process pres-
sure measurement. As pressure sensor
element, the dry ceramic-capacitive measur-
ing cell CERTEC
® is used. The process pres-
sure effects via the diaphragm a capacitance
change within the measuring cell. This ca-
pacitance change is detected by an ASIC
(application specific integrated circuit) and
converted into a pressure-proportional signal
by the integrated electronics module with
microcontroller. In addition, the process tem-
perature is detected via a sensor element
and converted into a temperature-dependent
signal. Precise, high-resolution digital
processing of measurement data ensures
excellent technical data.
The electronics module is powered by a
Profibus DP - PA segment coupler. The
measured pressure is transmitted via the
bus cable as a digital signal to the
processing system and can be displayed on
the indicating module or the external
indicating instrument VEGADIS 10.
The following adjustment variants are
available:
- adjustment module directly on VEGABAR
- adjustment modules in external housing
(VEGADIS 10)
- via PC with adjustment software VEGA
Visual Operating (VVO)
The instrument profile of VEGABAR behaves
according to profile specification version 3.0.
The instrument master file (GSD) is available
as download on the homepage of VEGA
(www.vega-g.de).
1.2 Self-monitoring
To improve reliability, the functionality of im-
portant electronic components is continu-
ously checked, and internal parameters such
as sensor value, temperature and operating
voltage are closely monitored.
VEGABAR 44 with the ceramic CERTEC ®
measuring cell offers the advantage of con-
tinuous self-monitoring. The measuring and
reference capacitances of the measuring cell
constitute a predefined ratio over the entire
measuring range. Any deviation from these
data is a reliable indicator of a malfunction of
the measuring cell.
If errors or malfunctions are detected during
these routines, fault signals are triggered
according to the Profibus PA specification.