General Description • Mounting • Connection
Analogue Level Measuring System
Consists of:
Rod probe KFS-1-... and separate evaluation unit KFA-1-...
The capacitive
is based on the three-electrode-principle, which allows measurements under extreme conditions. With this
measuring principle a counter-electrode is essential, which normally is provided by the metal container
(with non-metal containers an additional electrode is necessary, e. g. by means of a metal foil, which at a
minimum must cover the whole measuring area).
Advantages of the analogue three-electrode-measurement are:
•
Filling level measurements in containers and tubes up to approximately 5 m in diameter
For liquids and bulk materials ε ε ε ε ε
•
•
Due to its large measuring capacity it is also suitable for non-homogenous media
•
With the suitable mounting, virtually independent of the discharge cone
•
Probe suitable for use in an ambient temperature range of –70°C up to +250°C
•
Insensitive to static electrification
•
Because of automatic compensation of the dielectric constants useable for different materials
without re-adjustment
•
Complete adjustment in the empty-condition, easily achieved with adjustment-aids
Mounting
It is favourable to mount the analogue probes as shown on fig. 1. If necessary horizontal or preferably
diagonal mounting is also possible.The probe must be mechanically securely fixed,
no change of the position (for example side pressure from the filling cone, influence from stirring unit, etc.).
Fig.1
D
Measuring range (M) Reference range (R) non-active range (IB)
The probe can be mounted centrically or eccentrically.
For a measurement independent of the filling cone, we
recommend that the probe be mounted at a ¼ of the diameter.
The minimum distance between the upper switching point
and the conductive cover of the container is 50 mm.
Please take care that there is no material bridging between
probe and container wall.
Systems are suitable for analogue level measuring. The principle of operation
> 1,2
r
¼D
1/3D, min. 50 mm
IB
M
R
so that there will be
KFS-1-...
BE
Connect the BE container earth
over the shortest distance!
KFA-1-...
11