Schneider Electric Processor Adapter manual Two Types of Modbus Plus Networks

Using the Modbus Plus Ports

Two Types of Modbus Plus Networks

I/O Networks and In a distributed control environment, Modbus Plus can be used in either of two

Supervisory	ways:
Networks	λ As an I/O network
	λ As a supervisory network
	CAUTION
	CRITICAL I/O MUST BE SERVICED IN AN I/O NETWORK
	Design your Modbus Plus architecture to meet the needs of your network. Modbus Plus can
	offer deterministic I/O servicing or non-deterministic supervisory servicing of programming,
	user interface, and third party ModConnect devices. Do not use a supervisory network to
	service critical I/O.
	Failure to observe this precaution can result in injury or equipment damage.
I/O Networks
	In a deterministic I/O network architecture, one CPU services up to 63 Momentum
	I/O modules, Terminal I/O modules or other Modbus Plus devices.
	Note: When a programming panel or other human-machine interface (HMI)
	device is used as part of a deterministic Modbus Plus I/O network, it
	should be connected via the RS232 port on the CPU, not as a Modbus
	Plus node.
Supervisory
	In a supervisory architecture, several intelligent processing devices share system
Networks	data with each other. Many kinds of devices may be part of the network. You should
	be aware of each device’s requirement for access to the network and of the impact
	each device will have on the timing of your network communication, especially
	when servicing non-critical (and non-deterministic) I/O.
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