VEGA VEGAPULS 62 (≥ 2.0.0 - ≥ 4.0.0) 4 … 20 mA_HART - two-wire, approval according to LPR radio standard User Manual
Page 70
Specifications apply also to the current output
Temperature drift - Current output
±
0.03 %/10 K relating to the 16 mA span max.
±
0.3 %
Deviation on the current output by analogue/
digital conversion
<±
15 µA
Deviation on the current output by strong,
high frequency electromagnetic fields within
EN
61326
<±
150 µA
Influence of the superimposed gas and pressure to the accuracy
The propagation speed of the radar impulses in gas or vapour above the medium is reduced by
high pressure. This effect depends on the superimposed gas or vapour and is especially large at
low temperatures.
The following table shows the resulting deviation for some typical gases and vapours. The
specified values refer to the distance. Positive values mean that the measured distance is too
large, negative values that the measured distance is too small.
Gas phase
Temperature
Pressure
1
bar/
14
.5 psig
10
bar/
145
psig
50
bar/
725
psig
100
bar/
1450
psig
200
bar/
2900
psig
Air
20 °C/68 °F
0.00 %
0.22 %
1.2 %
2.4 %
4.9 %
200 °C/392 °F -0.01 %
0.13 %
0.74 %
1.5 %
3.0 %
400 °C/752 °F -0.02 %
0.08 %
0.52 %
1.1 %
2.1 %
Hydrogen
20 °C/68 °F
-0.01 %
0.10 %
0.61 %
1.2 %
2.5 %
200 °C/392 °F -0.02 %
0.05 %
0.37 %
0.76 %
1.6 %
400 °C/752 °F -0.02 %
0.03 %
0.25 %
0.53 %
1.1 %
Steam (satura-
ted steam)
100 °C/212 °F 0.26 %
-
-
-
-
180 °C/356 °F 0.17 %
2.1 %
-
-
-
264 °C/507 °F 0.12 %
1.44 %
9.2 %
-
-
366 °C/691 °F 0.07 %
1.01 %
5.7 %
13.2 %
76.0 %
Characteristics and performance data
Frequency
K-band (26 GHz technology)
Measuring cycle time
450 ms
Step response time
2)
≤
3 s
2)
Time span after a sudden measuring distance change by max. 0.5 m in
liquid applications, max 2 m with bulk solids applications, until the output
signal has taken for the first time 90 % of the final value (IEC 61298-2).
70
VEGAPULS
62 • 4 … 20 mA/HART - two-wire, approval according to LPR radio standard
11 Supplement
41718
-EN
-120301