Vega VEGACAL 67, Руководство по эксплуатации

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4 Mounting
VEGACAL 67 • For connection to a controller
31761-EN-200317
Fig. 4: Measures against moisture ingress
The process fitting must be sealed if there is gauge or low pressure in
the vessel. Before use, check if the seal material is resistant against
the measured product and the process temperature.
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.
Metric threads
In the case of instrument housings with metric thread, the cable
glands are screwed in at the factory. They are sealed with plastic
plugs as transport protection.
You have to remove these plugs before electrical connection.
Pressure/Vacuum
Vessel material
Vessel forms
Cable entries - NPT
thread
Cable glands