Schneider Electric Processor Adapter - Manual (Page 126)

Using the Modbus Ports
126 870 USE 101 10 V.2
Two-Wire Cabling Schemes for Modbus RS485 Networks
Introduction Two-wire cabling schemes may be used for single master/slave or multimaster/
slave communications. Masters may be located anywhere in the network.
Length The maximum length of cable from one end of network to other is 2000 ft. (609 m).
Number of
Devices The maximum number of devices in a network is 64 if all are Momentum devices.
Otherwise, the maximum is 32.
Termination One end of the cable run must be terminated with a terminating resistor (color code
is red).
The other end of the cable must be terminated with a terminating shunt, which
connects the transmit pair to the receiver pair (color code is blue).
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CAUTION
POTENTIAL FOR MULTIMASTER CONFLICTS
Configure a multimaster network carefully to avoid masters issuing simultaneous or
conflicting commands to the same slave module.
Failure to observe this precaution can result in injury or equipment damage.
Description Part Number
Modbus Plus or Modbus RS485 Terminating RJ45 Resistor Plugs
(pack of 2) 170 XTS 021 00
Modbus RS485 Terminating RJ45 Shunt Plugs 170 XTS 042 00