WR-30 Point-to-Point Wireless Bridge Instruction Manual
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Digital I/O Connector
All digital connections are referenced to ground. The primary
unit digital I/O settings determine the settings of the
secondary unit (e.g. if D1 of the primary unit is an input then
D1 of the secondary unit in an output).
Note:
Each connection may be set independently in the
device settings as either an input or an output. In the
diagram to the right, D4 & D3 are digital inputs and D2
is a digital output.
Modbus RTU Serial Communications
The WR-30 acts as a simple pass-through for Modbus communications. As such, multiple Modbus
enabled devices may be transmitted wirelessly using the WR-30 Wireless Bridge.
Note: Modbus Master must be connected to Primary Wireless Unit.
Figure 7. Three- and Five-Wire RS-485 Modbus Connections
Figure 8. Multiple Device RS-485 Modbus Connection
Notes:
1. Termination resistors are optional and values depend on the cable length and characteristic
impedance. Consult the cable manufacturer for recommendations.
2. Use shielded cable, twisted-pairs plus ground. Connect ground shield only at one location.
Figure 6. Digital I/O Connections
