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5 Connecting to power supply
VEGABAR 18 • Two-wire 4 … 20 mA
55575-EN-200327
5 Connecting to power supply
5.1 Preparing the connection
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, overvoltage arresters should
be installed
Warning:
Only connect or disconnect in de-energized state.
The data for power supply are specified in chapter "
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 operat-
ing voltage:
•
Lower output voltage of the power supply unit under nominal load
(e.g. with a sensor current of 20.5 mA or 22 mA in case of fault)
•
Influence of additional instruments in the circuit (see load values in
chapter "
Technical data
")
Use cable with round cross section. Depending on the plug connec-
tion, you have to select the outer diameter of the cable respectively so
that the seal effect of the cable gland is ensured.
Depending on the connection method or signal output, the device is
connected with standard two, three or four-wire cable without shield-
ing.
5.2 Connection procedure
Proceed as follows:
1. Loosen the screw on the rear of the plug connector
2. Remove the plug connector and seal from VEGABAR 18
3. Remove the plug insert from the plug housing
Safety instructions
Voltage supply
Connection cable
Plug according to
ISO 4400
