VEGA VEGATOR 121 - Manual (Page 10)

10
5 Connecting to power supply
VEGATOR 121 •
46107-EN-131217
5 Connecting to power supply
5.1 Preparing the connection
Always keep in mind the following safety instructions:
•
Connect only in the complete absence of line voltage
•
If overvoltage surges are expected, overvoltage arresters should
be installed
In hazardous areas you must take note of the respective regulations,
conformity and type approval certificates of the sensors and power
supply units.
The voltage supply can be 20 … 253 V AC/DC, 50/60 Hz. You can find
details on the voltage supply in the technical data.
The operating voltage of VEGATOR 121 is connected with standard
cable according to the national installation standards.
The sensors are connected with standard two-wire cable without
screen. If electromagnetic interference is expected which is above the
test values of EN 61326 for industrial areas, screened cable should
be used.
Connect the cable screen on both ends to ground potential. In the
sensor, the screen must be connected directly to the internal ground
terminal. The ground terminal on the outside of the sensor housing
must be connected to the potential equalisation (low impedance).
If potential equalisation currents are expected, the connection on the
processing side must be made via a ceramic capacitor (e. g. 1 nF,
1500 V). The low-frequency potential equalisation currents are thus
suppressed, but the protective effect against high frequency interfer-
ence signals remains.
Take note of the corresponding installation regulations for Ex applica-
tions. In particular, make sure that no potential equalisation currents
flow over the cable screen. In case of grounding on both sides this
can be achieved by the use of a capacitor or a separate potential
equalisation.
5.2 Connection procedure
The pluggable terminals can be removed as needed to allow more
convenient connection. To make the electrical connection, proceed as
follows:
1. Mount the instrument as described in the previous chapter
2. Connect sensor cable to terminal 1/2, and where applicable, con-
nect the screen
3. Connect power supply (switched off) to terminal 16/17
4. Connect relay to terminal 10/11/12
5. Option with fail safe relay: Connect relay to terminal 13/14/15
The electrical connection is finished.
Note safety instructions
Take note of safety
instructions for Ex
applications
Select power supply
Select connection cable
Cable screening and
grounding
Select connection
cable for Ex applica-
tions