User Manual

0,5 m (1.6 ft)
10 mm (0.394 in)
2 mm (0.079 in)
- 2 mm (- 0.079 in)
- 10 mm (- 0.394 in)
0
1 2 3
Fig. 31: Deviation under reference conditions
1 Reference plane
2 Antenna edge
3 Recommended measuring range
Reproducibility ≤ ±1 mm
Deviation with bulk solids The values are considerably application-depend-
ent. Firm specifications are hence not possible.
Variables influencing measurement accuracy
Temperature drift ±0.03 %/10 K relating to the 16 mA span max.
±0.3 %
Temperature drift - Digital output ±3 mm/10 K relating to the max. measuring range
or max. 10 mm
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
<±100 µA
Additional deviation through strong, high
frequency electromagnetic fields acc. to EN
61326
<±50 mm
Influence of the superimposed gas and pressure to the accuracy
The spreading speed of the radar impulses in gas or vapour above the medium is reduced by high
pressures. This e ffect 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 high,
negative values that the measured distance is too small.
VEGAPULS 62 • 4 … 20 mA/HART two-wire 57
11 Supplement
36503-EN-100607