Modbus Plus Applications

Modbus Plus Applications
Modbus Plus is a local area network system for industrial control applications. Networked devices can exchange messages for the control and monitoring of processes at remote locations in the industrial plant. Modicon products supporting Modbus Plus communication include programmable controllers and network adapters. The network is also supported by a variety of products from other manufacturers.
Each Modicon controller can connect to Modbus Plus directly from a port on its front panel. Additional networks can be accessed through Network Option Modules (NOMs) installed in the common backplane. The network also provides an efficient means for servicing input/output subsystems. Modicon Modbus Plus Distributed I/O (DIO) Drop Adapters
and Terminal Block I/O (TIO) modules can be placed at remote I/O sites
to allow the application to control field devices over the network link.

Extending the Network
Each network supports up to 64 addressable node devices. Up to 32 nodes can connect directly to the network cable over a length of 1500 ft (450 meters). Repeaters can extend the cable distance to its maximum of 6000 ft (1800 meters) and the node count to its maximum of 64. Fiber optic repeaters are available for longer distances.

Bridging Networks
Multiple networks can be joined through Bridge Plus devices. Messages originated on one network are routed through one or more bridges to a destination on another network.Bridgesare applicable to networks in which fully deterministic timing of I/O processes is not a requirement.In a network requiring deterministic I/O timing, messages for DIO/TIO nodes are passed on that network only, and do not pass through bridges. Modbus and custom RS232/RS485 serial devices can access Modbus Plus through Bridge Multiplexers. Each Bridge Multiplexer provides four configurable serial ports. A serial device can communicate with Modbus Plus networked devices, as well as with other devices at the serial ports.