Filter
Top Products
Chapter 6
Wiring digital communications
Topics covered in this chapter:
¨ Wire the transmitter to an RS-485 multidrop network
¨ Wire the transmitter to a Bell 202 multidrop network
Wire the transmitter to an RS-485 multidrop network
Prerequisites
Use twisted-pair, shielded cable that consists of 24 AWG (0.25 mm
2
) or larger wire between the
9739 MVD transmitter and
the RS-485 communication device. Maximum cable length is 4000 ft (1200 m).
Note
For long-distance communication, or if noise from an external source interferes with the signal, install a 120-Ω, 1/2-W
resistor at both ends of the network cable to reduce electrical reections.
Procedure
Use terminals 27 and 26 to wire the
9739 MVD transmitter to an RS-485 network.
Important
The Service port clips on the user interface of the 9739 MVD transmitter are directly connected to RS-485 terminals
(26 and 27). If you wire the transmitter for RS-485 digital communications, you cannot use the Service port clips for
communication with the transmitter.
36MicroMotion9739MVDTransmitters