VEGA Capacitive electrodes EL Profibus PA - Manual (Page 17)

Capacitive electrodes EL - Profibus PA 17
Mounting
Shortening of the electrode
Humidity
To avoid fraying the steel cable (EL 31) dur-
ing cutting, you must tin the cable around the
cutting position with a soldering iron or
blowtorch, or tightly wrap the cable with a
wire. Shorten the electrode cable with a metal
cutting saw or a cutting-off wheel by the
requested length.
Carry out an adjustment. The instruction is
under "4.1 Adjustment".
Filling opening
Install the electrode such that it does not
protrude directly into a strong filling stream.
Should such an installation location be neces-
sary, mount a suitable protective sheet metal
cover above or in front of the electrode e.g.
L 80 x 8 DIN 1028, etc.
Humidity from outside
To avoid moisture ingress, the connection
cables to the electrode housing of vertically
installed electrodes should be led downward
directly outside the cable entry. Rain and
condensation water can then drain off.
This is mainly valid for outdoor mounting, in
areas where high humidity is expected (e.g.
from cleaning processes) or for cooled or
heated vessels.
Cable entries
When mounting outdoors, on cooled vessels
or in humid areas where cleaning is done,
e.g. with steam or high pressure, the seal of
the cable entry is very important.
Use cable with a round cross-section con-
ductor and tighten the cable entry. The cable
entry is suitable for cable diameters of 5 mm
to 9 mm.
Metal vessel
Make sure that the mechanical connection of
the instrument to the vessel is electrically
conductive in order to ensure sufficient
grounding.
Use conductive seals such as e.g. copper,
lead etc. insulating measures, such as cover-
ing the thread with Teflon tape, can interrupt
the necessary electrical connection. In such
case, use the earth terminal on the housing to
connect the electrode to the vessel wall.