VEGA VEGABAR 83 4 … 20 mA - Operating Instructions User Manual
Page 61
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11 Supplement
VEGABAR 83 • 4 … 20 mA
45033-EN-131010
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
Ʋ Piezoresistive/strain gauge measur-
ing cell
depending on the process fitting and the chemical seal
Ʋ METEC
®
measuring cell
< 5 mbar/0.5 kPa (0.07 psig)
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.
The deviation corresponds to the value F
Kl
in chapter "Calculation of the total deviation". The value
results out of the accuracy class and the respective turn down.
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
0.075 %
< 0.075 %
< 0.015 % x TD
0.1 %
< 0.1 %
< 0.02 % x TD
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.
The thermal change of zero signal and output span corresponds to the value F
T
in chapter "Calcu-
lation of the total deviation (according to DIN 16086)".
Piezoresistive/strain gauge measuring cell
Turn down
In the compensated tem-
perature range 10 … +70 °C
(+50 … +158 °F)
Outside the compensated tem-
perature range
TD 1 : 1
< 0.05 %/10 K
typ. < 0.05 %/10 K
TD 1 : 1 up to 5 : 1
< 0.1 %/10 K
-
TD up to 10 : 1
< 0.15 %/10 K
-
Ceramic/Metal measuring cell - Standard
Medium or ambient tempera-
ture T
Accuracy class 0.1 %
Accuracy class 0.2 %
-40 … 0 °C (-40 … +32 °F)
< {0.15 % + 0.015 %/K x (-T)} x
{0.5+0.5 x TD}
< {0.1 % + 0.03 %/K x (-T)} x
{0.5+0.5 x TD}
0 … 40 °C (+32 … +104 °F)
< {0.0075 %/K x (T - 20 °C)} x
{0.5+0.5 x TD}
< {0.005 %/K x (T - 20 °C)} x
{0.5+0.5 x TD}
40 … 100 °C (+104 … +212 °F)
< {0.15 % } x {0.5+0.5 x TD}
< {0.005 %/K x (T - 20 °C)} x
{0.5+0.5 x TD}