VEGA VEGADIS 11 - Manual (Page 10)

5 C onnecting to power supply
5 .1 Preparing the connection
Always keep in mind the following safety instructions:
l
Connect only in the complete absence of line voltage
In hazardous areas you should take note of the appropriate
regulations, conformity and type approval certificates of the
sensors and power supply units.
VEGADIS 11 is connected with standard two-wire cable
without screen.
An outer cable diameter of 5 … 9 mm ensures the seal effect
of the cable entry. If electromagnetic interference is expected
which is above the test values of EN 61326 for industrial areas,
we recommend the use of screened cable.
Take note of the corresponding installation regulations for Ex
applications.
If screened cable is necessary, connect the cable screen on
both ends to ground potential. In the VEGADIS 11, the screen
must be connected directly to the internal ground terminal. The
ground terminal on the outside of the 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 interference signals remains.
In Ex applications, one-sided grounding on the sensor is
recommended, see EN 60079-14.
5 .2 Connection procedure
Proceed as follows:
1 Unscrew the housing cover
2 Loosen compression nut of the cable entry
3 Remove approx. 10 cm of the cable mantle, strip approx.
1 cm insulation from the individual wires
4 Insert the cable into VEGADIS 11 through the cable entry
Note safety instructions
Take note of
safety instruc-
tions for Ex ap-
plications
Selecting connection
cable
Select connec-
tion cable for Ex
applications
Cable screening and
grounding
Cable screen and
grounding for Ex appli-
cations
10 VEGADIS 11
Connecting to power supply
19888
-EN
-080227