2 principle of operation, 3 operation – VEGA VEGABAR 55 Foundation Fieldbus User Manual
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3 Product description
VEGABAR 55 • Foundation Fieldbus
36736-EN-130321
This operating instructions manual applies to the following instrument
versions:
•
Software from 3.82
3.2 Principle of operation
VEGABAR 55 is a pressure transmitter for use in the chemical, food
processing and pharmaceutical industries. Depending on the version,
it is used for level, gauge, absolute pressure or vacuum measure-
ment. Measured products are gases, vapours and liquids, also those
with higher temperatures.
The METEC
®
measuring cell is the measuring unit. It consists of
the ceramic-capacitive CERTEC
®
measuring cell and a special,
temperature-compensated isolating system.
The hydrostatic pressure of the product or the process pressure
causes a capacitance change in the measuring cell via the metallic
process diaphragm and the isolating liquid. This change is converted
into a corresponding output signal.
Power is supplied via the H1 Fieldbus. A two-wire cable according to
Fieldbus specification serves as carrier of both power and digital data
for multiple sensors. This cable can be operated in two versions:
•
via an H1 interface card in the control system and additional power
supply
•
via a Linking device with HSE (High speed Ethernet) and addi-
tional power supply according to IEC 61158-2
The DD (Device Descriptions) and CFF (capability files) necessary
for planning and configuration of your FF (Foundation Fieldbus) com-
munication network are available in the download area of the VEGA
homepage www.vega.com under "Services - Downloads - Software
- Foundation Fieldbus". The appropriate certificates are also available
there. A CD with the appropriate files and certificates can be ordered
via e-mail under [email protected] or by phone from one of the
VEGA agencies under the order number "DRIVER.S".
The backlight of the display and adjustment module is powered by the
sensor. Prerequisite is a certain level of operating voltage.
The data for power supply are specified in chapter "Technical data".
The optional heating requires its own operating voltage. You can find
details in the supplementary instructions manual "Heating for display
and adjustment module".
This function is generally not available for approved instruments.
3.3 Operation
The instrument can be adjusted with the following adjustment media:
•
With the display and adjustment module
•
with the suitable VEGA DTM in conjunction with an adjustment
software according to the FDT/DTM standard, e.g. PACTware and
PC
Scope of this operating
instructions manual
Application area
Functional principle
Power supply and bus
communication
DD/CFF