Schneider Electric Processor Adapter - Manual (Page 123)

Using the Modbus Ports
870 USE 101 10 V.2 123
Four-Wire Cabling Schemes for Modbus RS485 Networks
Introduction Four-wire cabling schemes may be used for single master/slave communications.
Only one master is allowed. The master 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 You must terminate both ends of the cable run with special terminating resistors.
Master Cable The master of this master/slave cabling scheme must be connected on at least one
side to a master cable, a special cable that crosses the transmit and receive lines.
The other side may be connected to a master cable, or, if the master is at one end
of the cable run, a terminating resistor.
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Description Part Number
Modbus Plus or Modbus RS485 Terminating RJ45 Resistor Plugs
(pack of 2).
Color code - red 170 XTS 021 00
Description Part Number
Modbus RS485 (RJ45/RJ45) Master Communication Cable 170 MCI 041 10
Modbus Plus or Modbus RS485 Terminating RJ45 Resistor Plugs
(pack of 2).
Color code - blue 170 XTS 021 00