11
5 Connecting to power supply
VEGATRENN 152 •
50783-EN-210419
If the resistance of the connected processing system is less than
230 Ω, the digital adjustment signal is extremely damped or short-cir-
cuited. Digital communication with the PC is then no longer possible.
With low impedance processing systems, a resistor of approx. 230 Ω
must be looped into the 4 … 20 mA cable. This resistor is already inte-
grated in VEGATRENN 152 and can be chosen through the selection
of the respective terminals.
Information:
When using a HART resistor, keep in mind that there is an additional
voltage loss. You can find details in chapter "
Technical data
".
No additional resistor is required in the sensor circuit for direct con-
nection of a HART-Master. When connecting a VEGADIS 82, the com-
munication resistor in the VEGADIS 82 must be deactivated.
Note:
It is possible to connect up to five HART sensors to one VEGATRENN
152. Several VEGATRENN can also be connected on the evaluation
side parallel to a PLC input, e.g. but the maximum number of connect-
able HART sensors is limited to a total of five because all intercon-
nected VEGATRENN form a common bus.
5.2 Connection procedure
The pluggable terminals can be removed as needed to allow more
convenient connection. To make the electrical connection, proceed as
follows:
1. Mount the instrument as described in the previous chapter
2. Connect sensor cable 2 to terminal 4/5, and where applicable,
connect the shielding
3. Connect sensor cable 1 to terminal 1/2, and where applicable,
connect the shielding
4. Connect processing circuit 2, e.g. from PLC to terminal 14/15 or
13/15 (with HART resistor), and shielding, if necessary
5. Connect processing circuit 1, e.g. from PLC to terminal 11/12 or
10/12 (with HART resistor), and shielding, if necessary
The electrical connection is finished.
Note:
If several sensors should be connected in HART multidrop mode, a
respective HART address must be assigned to each sensor before
connecting to VEGATRENN 152.
