Emerson 475, User Manual

Page: 58 / 114

Fieldbus Functionality
4-6
Field Hook-Up
Figure 4-4 illustrates one method of connecting the 475 Field Communicator to a
fieldbus segment. The 475 Field Communicator can be connected at any convenient
place along the bus (segment). In the field, this is typically done at the device or at the
fieldbus junction box.
Figure 4-4. Field Wiring Diagram Example
CAUTION
The 475 Field Communicator draws approximately 12 mA from the fieldbus segment.
Ensure the power supply or barrier on the fieldbus segment has the capacity to provide
this additional current. If a fieldbus segment is drawing near the capacity of the
segment’s power supply, connecting the 475 Field Communicator may result in loss of
communication.
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Fieldbus
Power
Conditioner
24 VDC
Power
Supply
Fieldbus
Junction
Box
Fieldbus
Host
Control
System
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