Connection Procedure - Vega VEGADIF 65 Operating Instructions Manual

Cable screening and
grounding
Connection cable
for Ex applications
Single/Double chamber
housing
VEGADIF 65 • 4 ... 20 mA
housing. This would influence the stability of the connection and the
tightness of the housing.
If screened cable is required, connect the cable screen on both ends
to ground potential.
In Ex systems, the grounding is carried out according to the installa-
tion regulations.
In electroplating plants as well as plants that apply cathodic corro-
sion protection, it must be taken into account that significant potential
differences exist. This can lead to unacceptably high currents in the
cable screen if it is grounded at both ends.
Information:
The metallic parts of the instrument (process fitting, housing, etc.) are
conductively connected to the ground terminal.
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

Proceed as follows:
1. Unscrew the housing lid
2. If a display and adjustment module is installed, remove it by turn-
ing it to the left
3. Loosen compression nut of the cable gland and remove blind
plug
4. Remove approx. 10 cm of the cable mantle, strip approx. 1 cm
insulation from the individual wires
5. Insert the cable into the sensor through the cable entry
6. Lift the opening levers of the terminals with a screwdriver (see
following illustration)
7. Insert the wire ends into the open terminals according to the wir-
ing plan
8. Press down the opening levers of the terminals, you will hear the
terminal spring closing
9. Check the hold of the wires in the terminals by lightly pulling on
them
10. Connect the screen to the internal ground terminal, connect the
external ground terminal to potential equalisation
11. Tighten the compression nut of the cable entry gland. The seal
ring must completely encircle the cable
12. Screw the housing lid back on
The electrical connection is finished.
5 Connecting to power supply
35