VEGA VEGABAR 87 4 … 20 mA - Operating Instructions User Manual
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11 Supplement
VEGABAR 87 • 4 … 20 mA
45507-EN-131010
Damping (63 % of the input variable),
adjustable
0 … 999 s
Dynamic behaviour output
Run-up time approx.
10 s
Dynamic characteristics, depending on medium, temperature and, if applicable, chemical seal
90 %
100 %
10 %
t
t
T
A
t
t
S
2
1
Fig. 25: Behaviour in case of sudden change of the process variable. t
T
: dead time; t
A
: rise time; t
S
: jump response
time
1 Process variable
2 Output signal
Dead time
> 45 ms
Rise time
> 35 ms (10 … 90 %)
Step response time
> 80 ms (ti: 0 s, 10 … 90 %)
Damping (63 % of the input variable)
0 … 999 s, adjustable
Reference conditions and actuating variables (according to DIN EN 60770-1)
Reference conditions according to DIN EN 61298-1
Ʋ Temperature
+15 … +25 °C (+59 … +77 °F)
Ʋ Relative humidity
45 … 75 %
Ʋ Air pressure
860 … 1060 mbar/86 … 106 kPa (12.5 … 15.4 psig)
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
< 0.2 mbar/20 Pa (0.003 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 specified values correspond to the value F
Kl
in chapter "Calculation of the total deviation".