Quantum NOM modules provide extended communication capabilities for the Quantum system within a Modbus and a Modbus Plus configuration.

Modbus, a master/slave protocol, is a de facto industry standard with support from over 500 industrial suppliers.

On-line programming or data acquisition applications are easily supported directly from the serial port of any computer.

Modbus can be used in either a simple point-to-point manner with a pair of devices, or in a network architecture with up to 247 slave devices.

Modbus Plus combines high speed, peer-to-peer communication and easy installation to simplify applications and reduce installation costs.

It allows host computers, controllers and other data sources to communicate as peers throughout the network via low-cost twisted pair cable or optional fiber optic cable.

As a deterministic token-passing network, Modbus Plus communicates at one megabaud for fast access to process data. It’s strength is its ability to control real-time control devices like I/O and drives, without degraded performance due to loading or traffic.

Bridging between Modbus and Modbus Plus is done automatically on CPUs and Modbus Plus network modules.

The bridge mode redirects Modbus messages onto the Modbus Plus network for easy connectivity between Modbus and Modbus Plus devices.

A summary of the available services on Quantum Modbus and Modbus Plus ports is given in the following table.

Quantum Modbus Plus on Fiber modules provides connectivity to Modbus Plus nodes by fiber cable without fiber optic repeaters.

The use of a 490 NRP 254 Fiber Optic Repeater allows the creation of a pure fiber optic network or a mixed fiber optic/twisted-pair network.