RESUMO
Data acquisition is a required step for any industrial application. Industrial automation traditionally relies on Supervisory Control and Data Acquisition (SCADA), and remote I/O is an important element of this infrastructure. The remote I/O is responsible for the data acquisition of sensors and actuators of industrial processes. The distributed I/O represents an evolution of the remote I/O to include processing and support network communication. With the adoption of recent technologies within the industry 4.0, automation solutions are facing servitization and being develop as a service. This paper describes the development of an open-source and low-cost distributed I/O as a service for industrial automation. The solution is based on a single board computer with I/O expansion modules, a microservice framework and a customized software to enable the I/O data acquisition to function in a networked, standardized, and scalable manner. Some application examples of the distributed I/O service are presented such as the I/O redundancy and historian, process control, and IIoT monitoring.