Emerson Smart Wireless THUM Adapter Reference Manual page 31

Reference Manual
00809-0100-4075, Rev CA
Figure 3-18. THUM adapter only, powered by a 24 V power supply with 1200 Ohm resistor
Ground
Figure 3-19. Wiring diagram for 2-wire device
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.
Mounting
to limit current to 20 mA
THUM Adapter
Remote Mount
Housing
Red
Green
Black
White
Yellow
250 Ohm
Resistor
THUM Adapter
Green
Red
Black
White
Yellow
THUM Adapter
Green
Red
Black
White
Yellow
+
24 V
Power
-
Supply
1200 Ohm
Resistor
Required
Wired Device
Ground
4-20 mA Loop +
4-20 mA Loop -
Splice Connector
- PWR / COMM
+ PWR / COMM
Wired Device
Ground
4-20 mA Loop +
4-20 mA Loop -
Resistor
- PWR / COMM
Splice Connector
+ PWR / COMM
Section 3: Mounting
March 2014
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