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5 connecting to power supply – VEGA PLICSRADIO T61 Wireless emitting unit User Manual

Page 14

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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