VEGA PLICSMOBILE T61 - Manual (Page 13)

13
5 Connecting to power supply
PLICSMOBILE T61 • External GSM/GPRS radio unit
37700-EN-130228
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
The operating voltage of PLICSMOBILE T61 is connected with stand-
ard cable according to the national installation standards.
The sensor connection cable included in the delivery is used to con-
nect the sensor.
Connect the cable screen on the sensor side 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 imped-
ance).
Note:
Remember that only 4 … 20 mA HART two-wire sensors from the
plics ® series with single chamber housing can be connected. The
connection is carried out via the I²C interface. Hence no additional ex-
ternal indication, such as e.g. VEGADIS 61, can be connected when
using PLICSMOBILE.
5.2 Connection options
Power can be supplied to the sensor and PLICSMOBILE in two ways:
With this version, only one voltage supply is required for both devices.
The voltage supply is connected to the PLICSMOBILE T61. In addi-
tion to the measured value, the sensor connection cable also carries
the voltage supply of the sensor. Hence there is no 4 … 20 mA signal
from the sensor electronics available for processing, e.g. via a PLC.
That's why the measured value transmission can only be carried out
exclusively via radio transmission through e-mail/SMS/WEB-VV.
With this version, the sensor and the PLICSMOBILE T61 are each
powered via a separate voltage supply. The measured values can
be transmitted via radio communication and the 4 … 20 mA signal
for processing, for example via a PLC, is available in parallel. If this
version is used, the two cores (no. 1/2) of the sensor connection
cable used for voltage supply are not required and must be isolated.
Two cable entries are now required on the sensor (1 x sensor con-
nection cable and 1 x external voltage supply). For this purpose, the
blind stopper on the sensor must be replaced by the attached cable
gland. Connection of the sensor supply is carried out according to the
respective operating instructions.
Note safety instructions
Select connection cable
Cable screening and
grounding
Common voltage supply
for sensor and PLICSMO-
BILE
Separate voltage supply
for sensor and PLICSMO-
BILE