keep in mind that measurement down to the tip of the probe is not
possible
.
T
he exact value of the min
.
distance
(
lower dead band
)
is
stated in chapter
"
T
echnical data
"
.
F
ig
.
3
:
V
essel with conical bottom
P
lastic vessel
/
G
lass vessel
T
he guided microwave principle requires a metal surface on the
process
fi
tting
.
T
herefore use in plastic vessels etc
.
an instrument
version with
fl
ange
(
from
DN
50
)
or place a metal sheet
(
ø
>
200
mm
/
8
in
)
beneath the process
fi
tting when screwing it in
.
M
ake sure that the plate has direct contact with the process
fi
tting
.
I
n bypass tubes of plastic
,
a metal screen must be provided on the
outside
.
Y
ou can glue metal foil
,
for example
,
on the outside along the
entire length of the tube
.
T
his metal screen must be connected to the
ground terminal on the instrument
.
W
hen installing rod or cable probes without metal vessel wall
,
e
.
g
.
in
plastic vessels
,
the measured value can be in
fl
uenced by strong
electromagnetic
fi
elds
(
emitted interference according to
EN
61326
:
class
A
).
I
n this case
,
use a probe in coax version
.
V
essel type
12
VEGAFLEX
61
•
P
ro
fi
bus
PA
4
M
ounting
31835
-
EN
-
100426
