VEGA VEGAPULS 67 (≥ 2.0.0 - ≤ 3.8) 4 … 20 mA_HART two-wire - Manual (Page 52)

Input variable
M easured variable distance between process fitting and product sur-
face
M in. distance from antenna end 50 mm (1.969 in) 3)
M easuring range up to 15 m (49.21 ft)
Reference conditions to measuring accuracy (similar to DIN EN 60770-1)
R eference conditions according to DIN EN 61298-1
-
T emperature
+ 18 … +30 °C (+64 … +86 °F)
-
R elative humidity 45 … 75 %
-
A ir pressure 860 … 1060 mbar/86 … 106 kPa (12.5 … 15.4 psig)
O ther reference conditions
-
R eflector ideal reflector, e.g. metal plate 2 x 2 m
-
F alse reflections L argest false echo 20 dB smaller than the useful
echo
Characteristics and performance data
F requency K- band
I nterval approx. 1 s
B eam angle -3 dB 4) 10°
S tep response or adjustment time 5) > 1 s (dependent on the parameter setting)
M
ax. level change
A
djustable up to 1 m/min. (dependent on the
parameter settings)
M ax. emitted HF power of the antenna system
-
P ulse peak power < 10 mW
-
P ulse duration < 2 ns
-
A verage power < 25 µW
-
A verage power with 1 m distance
< 1 µW/ cm 2
Measuring accuracy
R esolution, general max. 1 mm (0.039 in)
D eviation 6) see diagrams
3) I n products with low dielectric value up to 50 cm (19.69 in).
4) C orresponds to the range with 50 % of the emitted power
5) T ime to output the correct level (with max. 10 % deviation) after a sudden
level change.
6) I ncl. non-linearity, hysteresis and non-repeatability.
52 VEGAPULS 67 • 4 … 20 mA/HART two-wire
10 S upplement
32938
-EN
-100514