Siemens sitrans LR 400 Instruction Manual page 27

Warning: The coupling module (shown below) may not be used in areas
where there is an explosion hazard and may not be connected to
intrinsically safe circuits.
The electrical connection of the PC/Laptops and the HART-Communicator to the 4-20-mA
signal cable is shown below.
Connection, HART Schematic Diagram
HART Communicator 275
Note:
A 250 ohm loop resistor may be required, depending on PLC input resistance.
The connection of the PC/Laptops and Profibus-PA to the 4-20 mA signal cable is shown
below.
Connection, Profibus Schematic Diagram
Class 1
Master
DP/PA
Coupler
SITRANS LR 400
7ML19985FH03
PLC
Profibus-PA
SITRANS LR 400
SITRANS LR 400 – INSTRUCTION MANUAL
PLC with mA
input card
HART
SITRANS LR 400
Class 2
PDM
Master
SITRANS LR 400
PC/laptop with HART
modem running PDM
ET200
HART
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