2 principle of operation – VEGA VEGABAR 61 Foundation Fieldbus User Manual

Page 9

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Article number instrument

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Technical data: Measuring range, process pressure, process
temperature, signal output, voltage supply, protection, protection
class

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Order number

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Article numbers documentation

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Serial number

With the serial number, you can access the delivery data of the
instrument via www.vega.com, "VEGA Tools" and "serial number
search
". In addition to the type label outside, you can also find the
serial number on the inside of the instrument.

Instruments in the version "Oil and grease-free for oxygen applica-
tions
" are equipped with a supplementary label. The supplementary
label contains instructions on oil and grease-free parts of the
instrument.

3.2 Principle of operation

The VEGABAR 61 is a pressure transmitter with isolating diaphragm
for pressure measurement of highly corrosive and hot liquids.

The sensor element for measuring ranges up to 60 bar is the
CERTEC

®

measuring cell with rugged ceramic diaphragm. The

hydrostatic pressure of the product or the process pressure causes a
capacitance change in the measuring cell via the metal process
diaphragm and the isolating system.

1)

The sensor element for measuring ranges from 100 bar is a wire strain
gauge (DMS) on the rear of the process diaphragm. There, the
process pressure causes a resistance change, which is converted into
an appropriate 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:

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via an H1 interface card in the control system and additional power
supply

1)

The isolating system protects the sensor against corrosive products and
high temperatures. By selecting suitable diaphragm materials and isolating
liquids, systems with a temperature resistance up to 400 °C (752 °F) can be
achieved.

Supplementary label
"O

il and grease-free for

oxygen applications"

Application area

Functional principle

Power supply and bus
communication

VEGABAR

61 • Foundation Fieldbus

9

3 Product description

28258

-

EN

-081209

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