VEGA VEGABAR 81 4 … 20 mA_HART - Operating Instructions User Manual

Page 66

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66

11 Supplement

VEGABAR 81 • 4 … 20 mA/HART

45018-EN-131010

Reference conditions and actuating variables (according to DIN EN 60770-1)
Reference conditions according to DIN EN 61298-1

Ʋ Temperature

+18 … +30 °C (+64 … +86 °F)

Ʋ Relative humidity

45 … 75 %

Ʋ Air pressure

860 … 1060 mbar/86 … 106 kPa (12.5 … 15.4 psi)

Determination of characteristics

Limit point adjustment according to IEC 61298-2

Characterstic curve

Linear

Reference installation position

upright, diaphragm points downward

Influence of the installation position

depending on the chemical seal version

Deviation (according to IEC 60770)
Applies to the digital signal output (HART, Profibus PA, Foundation Fieldbus) as well as to the

analogue current output 4 … 20 mA and refers to the set span. Turn down (TD) is the ratio nominal

measuring range/set span.

Accuracy class

Non-linearity, hysteresis and re-

peatability with TD 1 : 1 up to 5 : 1

Non-linearity, hysteresis and re-

peatability with 5 : 1

0.2 %

< 0.2 %

< 0.04 % x TD

Influence of the product or ambient temperature
Thermal change zero signal and output span
Applies to the digital signal output (HART, Profibus PA, Foundation Fieldbus) as well as to the

analogue current output 4 … 20 mA and refers to the set span. Turn down (TD) is the ratio nominal

measuring range/set span.

Average temperature coefficient

zero signal

In the compensated tem-

perature range 10 … +70 °C

(+50 … +158 °F)

Outside the compensated tem-

perature range

Turn down 1 : 1

< 0.05 %/10 K

typ. < 0.05 %/10 K

Turn down 1 : 1 up to 5 : 1

< 0.1 %/10 K

-

Turn down up to 10 : 1

< 0.15 %/10 K

-

Thermal change, current output
Applies also to the analogue 4 … 20 mA current output and refers to the set span.
Thermal change, current output

< 0.05 %/10 K, max. < 0.15 %, each with -40 … +80 °C

(-40 … +176 °F)

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