VEGA VEGAPULS 63 (≥ 2.0.0 - ≥ 4.0.0) Profibus PA - Manual (Page 60)

60
11 Supplement
VEGAPULS 63 • Profibus PA
36513-EN-130228
Accuracy (according to DIN EN 60770-1)
Process 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 psig)
Installation reference conditions
Ʋ Min. distance to installations > 200 mm (7.874 in)
Ʋ Reflector Plane plate reflector
Ʋ False reflections Biggest false signal, 20 dB smaller than the useful signal
Deviation with liquids See following diagrams
0,5 m (1.6 ft)
10 mm (0.394 in)
- 10 mm (- 0.394 in)
0
2 mm (0.079 in)
- 2 mm (- 0.079 in)
1 2 3
Fig. 48: Deviation under reference conditions
1 Reference plane
2 Antenna edge
3 Recommended measuring range
Repeatability ≤ ±1 mm
Variables influencing measurement accuracy
Temperature drift - Digital output
±3 mm/10 K relating to the max. measuring range or
max. 10 mm
Additional deviation through electromag-
netic interference acc. to EN 61326
< ±50 mm
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.