Modbus RTU & Modbus TCP Communications & Components

Modbus RTU is an industrial communication protocol developed in 1979 used to establish communication between intelligent devices. It is one of the most widely used network protocol in the industrial manufacturing environment.

Modbus™ TCP is the Modbus variant used for communication over TCP networks between machines. Ethernet has become the standard of corporate enterprises and is becoming more common for factory networking. Using Modbus TCP in the factory allows true integration with the corporate Intranet and systems that support the factory.

For more information visit www.modbus.org.

Advantage has implemented Modbus™ RTU communication on these instruments:

• Sentra Temptender
• Sentra G
• Sentra G-300
• Sentra T-300
• Regal T-500
• Regal G-500
• Multizone (MZC)

The physical connection is made using the standard RS-485 port.

Advantage has also implemented Modbus™ TCP on these instruments:

• Sentra Temptender
• Sentra Temptender
• Sentra G
• Sentra G-300
• Sentra T-300
• Regal T-500
• Regal G-500
• Multizone (MZC)

In the case of Modbus™ TCP a circuit board is attached to the standard instrument to convert the Modbus™ RTU to Modbus™ TCP. An industrial grade RJ45/IP67 connector is generally provided on the unit to easily connect to the plant network. A variety of connectors can be supplied to meet customer needs and facility standards.

While Modbus™ RTU is a standard feature on the instruments listed, Modbus™ TCP requires additional components at an additional cost.

The Modbus™ RTU and Modbus™ TCP interface allows the instrument to communicate with a variety of devices including primary processing equipment controls, PLC’s and many more. Modbus™ can communicate information including setpoint, retransmit of setpoint, actual temperature, deviation alarm, sensor failure and remote start/stop. (Remote start/stop via Modbus™ is not available on Multizone MZC instruments.)

The Modbus™ TCP interface can be configured to any user IP/Subnet. Configuration is achieved using a utility program that runs on Windows™ based PC’s. Download at http://www.lantronix.com/products/deviceinstaller/

Temperature Control Units : Sentra Series

Temperature Controllers : Regal Units

Central Chillers : Multizone Units

Modbus™ / TCP Register Definitions for Sentra Temptender, Sentra G, Sentra G-300 & Sentra T-300 Rev 1.1

Modbus™ / TCP Register Definitions for Regal G-500 and Regal T-500 Rev 1.1

Modbus™ / TCP Register Definitions for Multizone III (MZC III) Instrument Rev 1.1