Vega VEGAPULS 62, Руководство по эксплуатации

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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
F ig .
31
: D eviation under reference conditions
1
R
eference plane
2
A ntenna edge
3 R ecommended measuring range
R eproducibility ≤ ±
1
mm
D eviation with bulk solids T he values are considerably application - depend -
ent . F irm speci fi cations are hence not possible .
V ariables in fl uencing measurement accuracy
T emperature drift ±
0
.
03
% /
10
K relating to the
16
m A span max .
±
0
.
3
%
T emperature drift - D igital output ±
3
mm /
10
K relating to the max . measuring range
or max .
10
mm
D eviation on the current output by analogue /
digital conversion
<±
15
µ
A
D eviation on the current output by strong ,
high frequency electromagnetic fi elds within
EN
61326
<±
100
µ
A
A dditional deviation through strong , high
frequency electromagnetic fi elds acc . to EN
61326
<±
50
mm
I n fl uence of the superimposed gas and pressure to the accuracy
T he spreading speed of the radar impulses in gas or vapour above the medium is reduced by high
pressures . T his e ff ect depends on the superimposed gas or vapour and is especially large at low
temperatures .
T he following table shows the resulting deviation for some typical gases and vapours . T he
speci fi ed values refer to the distance . P ositive values mean that the measured distance is too high ,
negative values that the measured distance is too small .
VEGAPULS
62
•
4
…
20
m A / HART two - wire
57
11
S upplement
36503
-
EN
-
100607