5 connecting to power supply – VEGA PLICSRADIO T61 Wireless emitting unit User Manual
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5 Connecting to power supply
PLICSRADIO T61 • Wireless emitting unit (single channel)
32865-EN-130322
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.
Two types of power supply unit are available. You can find detailed
information on the power supply in chapter "Technical data" in the
"Supplement".
The operating voltage of PLICSRADIO T61 is connected with stand-
ard cable according to the national installation standards.
Standard two-wire cable with screen can be used for connecting the
sensors. The screening is absolutely necessary to ensure interfer-
ence-free operation with HART sensors.
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 screen connec-
tion on the side of PLICSRADIO T61 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.
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 steps sensor
Proceed as follows:
1. Loosen the four screws on the housing socket with an Allen key
2. Remove the mounting plate from the housing socket
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