Connecting To A Fieldbus Device - Emerson 475 User Manual

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Connecting to a fieldbus
device
Connect the 475 Field Communicator by using the lead set with the
appropriate connectors in parallel with the device. Due to
measurement circuitry, the 475 Field Communicator fieldbus
connectors on the communication terminals are polarity sensitive. An
error message appears if the lead set is connected incorrectly.
For information about Intrinsically Safe connections, see Appendix B.
NOTE
Dynamic variables shown while online represent the digital data being
sent from the device.
Digital communication is susceptible to electrical noise; follow proper
wiring instructions.
Fieldbus communication terminals
Three terminals for the lead set are on the top of the 475 Field
Communicator. Each red terminal is a positive connection for its
protocol. The black terminal is a common terminal shared by both
protocols. An access door ensures only one pair of terminals is
exposed at any one time; see Figure 4-2. Several markings indicate
which pair of terminals is for which protocol.
Figure 4-2. Fieldbus communication terminals and access door
Communication terminals
Fieldbus communication terminal markings
Fieldbus functionality
Access door