Sometimes referred to as I/O servers or I/O gateways, these modules measure temperature, volts and mA signals, and pass the measured values back to your master computer using Modbus/ TCP or other Ethernet based protocols. Digital status signals such as alarms or switches can also be monitored, while digital outputs can control pumps of other on/off devices.
The Moxa ioLogik series add local logic control, while retaining communication over Ethernet
An especially useful feature of some devices here is called “i2o” by Acromag , “io mirroring” by Moxa or “tunnelling”. These particular devices can measure a analog or digital signal, then transmit over Ethernet to another device which will output the same signal. This is achieved without the need for a PC to control the operation.
