VEGA VEGABAR 51 Foundation Fieldbus User Manual

Page 46

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46

10 Supplement

VEGABAR 51 • Foundation Fieldbus

36715-EN-130321

Ʋ Physical layer

according to IEC 61158-2

Channel Numbers

Ʋ Channel 1

Primary value

Ʋ Channel 2

Secondary value 1

Ʋ Channel 3

Secondary value 2

Ʋ Channel 4

Temperature value

Transmission rate

31.25 Kbit/s

Current value

10 mA, ±0.5 mA

Dynamic behaviour output
Run-up time approx.

10 s

90 %

100 %

10 %

t

t

T

A

t

t

S

2

1

Fig. 26: Sudden change of the process variable, dead time t

T

, rise time t

A

and step response time t

S

1 Process variable

2 Output signal

Dead time

≤ 150 ms

Rise time

≤ 100 ms (10 … 90 %)

Step response time

≤ 250 ms (ti: 0 s, 10 … 90 %)

To this amounts the reaction time of the isolatng system. This time varies from values < 1 s with

compact chemical seals to several seconds with capillary systems.
Example: Flange-type chemical seal DN 80, filling silicone oil KN 2.2, capillary length 10 m, meas-

uring range 1 bar

Process temperature

Reaction time

40 °C

approx. 2 s

20 °C

approx. 3 s

-20 °C

approx. 11 s

Damping (63 % of the input variable)

0 … 999 s, adjustable

Input variable
Adjustment
Adjustment range of the min./max. adjustment relating to the nominal measuring range:

Ʋ Percentage value

-10 … 110 %

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