Vega VEGAPULS 63 Operating Instructions Manual page 63

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
Air 20 °C/68 °F
200 °C/392 °F -0.01 %
400 °C/752 °F -0.02 %
Hydrogen 20 °C/68 °F
200 °C/392 °F -0.02 %
400 °C/752 °F -0.02 %
Steam (satu- 100 °C/212 °F 0.26 %
rated steam)
180 °C/356 °F 0.17 %
264 °C/507 °F 0.12 %
366 °C/691 °F 0.07 %
Characteristics and performance data
Measuring frequency
Measuring cycle time
Ʋ Standard electronics approx.
Ʋ Electronics with increased sensitivity
approx.
Step response time
2)
Beam angle
3)
Ʋ Clamp 2", 3"
Ʋ Clamp 3½", 4"
Ʋ Bolting DN 50
Ʋ Bolting DN 80
Ʋ flange DN 50, ANSI 2"
Ʋ Flange DN 80 ... DN 150, AN-
SI 3" ... 6"
Emitted HF power (depending on the parameter adjustment)
Ʋ Average spectral transmission power
density
Time span after a sudden measuring distance change by max. 0.5 m in liquid applications, max 2 m with bulk
2)
solids applications, until the output signal has taken for the first time 90 % of the final value (IEC 61298-2).
Outside the specified beam angle, the energy of the radar signal has a level which is reduced by 50 % (-3 dB)
3)
EIRP: Equivalent Isotropic Radiated Power
4)
VEGAPULS 63 • 4 ... 20 mA/HART two-wire
1 bar 10 bar
(14.5 psig) (145 psig)
0.00 % 0.22 %
0.13 %
0.08 %
-0.01 % 0.10 %
0.05 %
0.03 %
-
2.1 %
1.44 %
1.01 %
K-band (26 GHz technology)
450 ms
700 ms
≤ 3 s
18°
10°
18°
10°
18°
10°
-14 dBm/MHz EIRP
Pressure
50 bar 100 bar
(725 psig) (1450 psig)
1.2 % 2.4 %
0.74 % 1.5 %
0.52 % 1.1 %
0.61 % 1.2 %
0.37 % 0.76 %
0.25 % 0.53 %
- -
- -
9.2 % -
5.7 % 13.2 %
4)
11 Supplement
200 bar
(2900 psig)
4.9 %
3.0 %
2.1 %
2.5 %
1.6 %
1.1 %
-
-
-
76.0 %
63