Modbus™ is an industrial communication protocol developed in 1979 used to establish master slave/client server communication between intelligent devices. It is the most widely used network protocol
in the industrial manufacturing environment.
Modbus™ TCP/IP (Ethernet) is the common transport protocol of the internet and Modbus™ TCP/IP can provide a reliable data transport mechanism between machines. Ethernet has become the standard of corporate enterprises
and is becoming more common for factory networking. Using Ethernet TCP/IP in the factory allows true integration with the corporate intranet and systems that support the factory.
Advantage has implemented Modbus™ TCP/IP on several instruments. As shown below, left to right, Sentra Temptender, Sentra G, Sentra HE, Regal HE, Maximum HE and Multizone MZC-3 instruments. The physical connection is made using the standard RS-485 port.
A circuit board is attached to the standard instrument to convert the ModbusTM RTU to ModbusTM TCP/IP. 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.
The Modbus™ RTU and Modbus™ TCP/IP 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 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.
Advantage instrument with Modbus͐2 TCP/IP add-on circuit board.
Close up view of the Modbus™ TCP/IP connection and circuit board.
Example of industrial grade RJ45/IP67 port connection for Modbus™ TCP/IP network interface.
RS-485 communications port used on Advantage instruments for SPI and Modbus™ RTU communications.
For more information about Modbus Communications and Components call the Advantage Sales Department at 317-887-0729.
Modbus / TCP Register Definitions
Sentra Temptender, Sentra G and Sentra HE Instruments
Regal HE Instrument
Multizone III (MZC III) Instrument
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