APP NOTE: Ethernet I/O Simplifies Communication Between One PLC and Multiple Remote Locations

This document illustrates using Acromag’s BusWorks® XT Ethernet I/O modules to split one signal from a central control room PLC and control multiple remote locations using Ethernet protocol.

Defining the Problem:

A customer has multiple remote locations linked over an Ethernet network, each requiring discrete outputs. They all need to be sent the same communication signal at the same time.

System Requirements:

• All remote sites need to be controlled simultaneously from one central control room via Ethernet protocol

Implementing the Solution:

1. Set up the Ethernet comunication between master
PLC device and the BusWorks XT discrete I/O modules (XT1111)
2. Connect the field instruments and verify input
status using the software test & polling feature
3. Program the BAS with the remote I/O network
parameters and Modbus registers.

Featured Products:

  • 16-Channel Discrete I/O, Modbus/TCP XT1111-000
  • 16-Channel Discrete I/O, with Counter/Timers 989EN-4016
  • Software Interface Package XT-SIP

Why Acromag: 

Our BusWorks XT Modbus/TCP remote I/O modules include a peer-to-peer feature known as i2o, where two or more slaves can talk to each other without requiring a master. With i2o communication, one signal from the PLC is split by the XT1111 modules and sent to multiple locations. The XT1111 automatically re-transmits the discrete level to each 989EN module’s IP address, thus reproducing the status of the original PLC input.