Mounting Instructions; Connecting To Power Supply; Preparing The Connection - SICK LFC Manuel De Mise En Service

4.2

Mounting instructions

Adhesive products
In adhesive and viscous products, the surfaces
of the sensor should protrude into the vessel
to avoid buildup. Therefore mounting bosses
should not exceed a certain length.
Abb. 14: Adhesive products
In horizontal pipelines, avoid mounting in the
upper or lower area of the pipe.
In the upper part of the pipe cavities can form
due to air inclusions.
Solids can settle in the lower pipe area. Both
can lead to measurement errors.
In horizontal pipelines, lateral installation is
therefore recommended.
A
B
Abb. 15: Installation in horizontal pipelines
x Recommended mounting area
A Not recommended - danger of air inclusions
B Not recommended - Danger of buildup
Inflowing medium
If LFC is mounted in the filling stream, unwanted
false measurement signals can be generated.
For this reason, mount LFC at a position in the
vessel where no disturbances, e.g. from filling
openings, agitators, etc., can occur.
LFC • Transistor (PNP)

5 Connecting to power supply

5 Connecting to power
supply
5.1

Preparing the connection

Safety instructions
Always keep in mind the following safety
instructions:
•
Carry out electrical connection by trained,
qualified personnel authorised by the plant
operator
•
If overvoltage surges are expected, overvol-
tage arresters should be installed
Warning:
Only connect or disconnect in de-ener-
gized state.
Voltage supply
The data for power supply are specified in chap-
ter "Technical data".
Note:
Power the instrument via an energy-
limited circuit (power max. 100 W) acc.
to IEC 61010-1, e.g.
•
Class 2 power supply unit (acc. to UL1310)
•
SELV power supply unit (safety extra-low
voltage) with suitable internal or external
limitation of the output current
Keep in mind the following additional factors
that influence the operating voltage:
•
Lower output voltage of the power supply
unit under nominal load
•
Influence of additional instruments in the
circuit (see load values in chapter "Technical
data")
Connection cable
The instrument is connected with standard
four-wire cable. If electromagnetic interference
is expected which is above the test values of
EN 61326-1 for industrial areas, screened cable
should be used.
•
M12 x 1 plug
Plug connections
Make sure that the cable and the plug used ha-
ve the required temperature resistance and fire
safety for max. occurring ambient temperature.
When mounting outdoors, on cooled vessels or
in moist areas in which cleaning is made with
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