Emerson Rosemount Smart Wireless THUM, Reference Manual

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Reference Manual
00809-0100-4075, Rev BA
October 2010
Smart Wireless THUM Adapter
3-12
Figure 3-20. Wiring Diagram for
2-Wire Device with Resistor
NOTE
A passive loop exists when the wired device is not supplying power to the
4-20 loop. It is important to verify if the wired device is operating in active or
passive mode.
Figure 3-21. Wiring Diagram for
4-Wire Passive Device
Figure 3-22. Wiring Diagram for
4-Wire Passive Device with
Resistor
NOTE
An active loop exists when the wired device is supplying power to the 4-20
mA loop. It is important to verify if the wired device is operating in an active or
passive mode.
Splice Connector
Wired Device
4-20 mA Loop -
4-20 mA Loop +
Ground
- PWR / COMM
+ PWR / COMM
THUM Adapter
Green
Red
Black
White
Yellow
Resistor
Splice Connector
Wired Device
4-20 mA Loop -
4-20 mA Loop +
Ground
Power +
Power -
THUM Adapter
Green
Red
Black
White
Yellow
Power+
Power-
4-20 mA/HART -
4-20 mA/HART +
Splice Connector
Wired Device
4-20 mA Loop -
4-20 mA Loop +
Ground
Power +
Power -
THUM Adapter
Green
Red
Black
White
Yellow
Power+
Power-
4-20 mA/HART -
4-20 mA/HART +
Resistor