Connecting To Power Supply; Preparing The Connection; Connecting; Wiring Plan - SICK LFC Manual De Instrucciones

5 Connecting to power supply

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.
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.
22
•
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 cir-
cuit (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, shielded cable
should be used.
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
steam or high pressure, it is very important that
the plug is screwed on correctly.
5.2

Connecting

Instrument versions
Abb. 16: LFC - M12 x 1 plug
1 Plug connection
2 360° status indication
3 Instrument housing
4 Process fitting
5 Sensor
M12 x 1 plug connection
This plug connection requires a prefabricated
cable with plug. Depending on the version,
protection IP66/IP67 or IP69.
5.3

Wiring plan

For connection to binary inputs of a PLC.
1
2
3
4
5
LFC • Transistor (PNP)