VEGA VEGAPULS 68 (≥ 2.0.0 - ≥ 4.0.0) Modbus and Levelmaster protocol - Manual (Page 63)

63
11 Supplement
VEGAPULS 68 • Modbus and Levelmaster protocol
41370-EN-121011
Ʋ Min. distance to installations > 200 mm (7.874 in)
Ʋ Reflector Plane plate reflector
Ʋ False reflections Largest false echo 20 dB smaller than the useful echo
Deviation with liquids See following diagrams
1,0 m (3.28 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. 50: Deviation under reference conditions
1 Reference plane
2 Antenna edge
3 Recommended measuring range
Reproducibility ≤ ±1 mm
Deviation with bulk solids The values depend to a great extent on the application.
Binding specifications are thus not possible.
Deviation under EMC influence ≤ ±30 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 strong, high
frequency electromagnetic fields acc. to
EN 61326
< ±50 mm
Characteristics and performance data
Measuring frequency
K-band (26 GHz technology)
Measuring cycle time approx. 700 ms
Step response time 1) ≤ 3 s
Tracking speed of the measuring window
max.
1 m/min
Beam angle 2)
Ʋ Horn antenna ø 40 mm (1.575 in) 20°
Ʋ Horn antenna ø 48 mm (1.89 in) 15°
Ʋ Horn antenna ø 75 mm (2.953 in) 10°
1) 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).
2) Outside the specified beam angle, the energy of the radar signal has a level which is reduced by 50 % (-3 dB)