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5 Connecting to power supply
VEGAPOINT 21 • Transistor (NPN/PNP)
56623-EN-210210
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
•
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.
The instrument is connected with standard four-wire cable. If electro-
magnetic interference is expected which is above the test values of
EN 61326-1 for industrial areas, shielded cable should be used.
•
Valve plug ISO 4400, ø 4.5 … 7 mm
•
Valve plug ISO 4400 with IDC crimping technology, ø 5.5 … 8 mm
•
Valve plug ISO 4400 with hinged cover, ø 4,5 … 7 mm
Safety instructions
Voltage supply
Connection cable
