Data Exchange

Original instructions

Exchanges

Data exchanges take place in one of two modes:

server mode: All Modbus-over-TCP requests from the PLC are supported by the Ethernet module.
client mode: This type of exchange enables Modbus-over-TCP requests to be sent using the functions:
- READ_VAR
- WRITE_VAR
- DATA_EXCH (see the Communication Block Library for Control Expert)

PLC

programmable logic controller. The PLC is the brain of an industrial manufacturing process. It automates a process as opposed to relay control systems. PLCs are computers suited to survive the harsh conditions of the industrial environment.