VEGA VEGACAL 67 Foundation Fieldbus - Manual (Page 14)

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4 Mounting
VEGACAL 67 • Foundation Fieldbus
31760-EN-130917
The max. permissible pressure is specified in chapter "Technical
data" or on the type label of the sensor.
Insulating measures, such as e.g. covering the thread with teflon tape,
can interrupt the necessary electrical connection with metal vessels.
For this reason, ground the probe on the vessel or use a conductive
seal material.
Metal vessel
Make sure that the mechanical connection of the probe to the vessel
is electrically conductive to ensure sufficient grounding.
Use conductive seals, such as those made of copper or lead, etc.
Insulating measures, such as covering the thread with Teflon tape,
can interrupt the necessary electrical connection with metal vessels.
For this reason, ground the probe on the vessel or use a conductive
seal material.
Non-conductive vessels
In non-conductive vessels, e.g. plastic tanks, the second pole of the
capacitor must be provided separately.
If possible, the capacitive probe should be mounted vertically or par-
allel to the counter electrode. This applies particularly to applications
in non-conductive products.
In cylindrical tanks, spherical tanks or other asymmetrical tank forms,
nonlinear level values are generated due to the varying distance to
the vessel wall.
Use a concentric tube in non-conductive products or linearize the
meas. signal.
4.2 Mounting instructions
If the instrument is mounted in the filling stream, unwanted false
measurement signals can be generated. For this reason, mount the
instrument at a position in the vessel where no disturbances, e.g. from
filling openings, agitators, etc., can occur.
This applies particularly to instrument versions with a longer probe.
Vessel material
Vessel forms
Inflowing medium