Recently i implemented a JAVA API for WinCC Open Architecture. So, it is possible to implement WinCC OA API Manager in Java. I used this to implement a simple API Manager in Java to connect WinCC OA to MQTT.

MQTT is a machine-to-machine (M2M) “Internet of Things” connectivity protocol. It was designed as an extremely lightweight publish/subscribe messaging transport. It is useful for connections with remote locations where a small code footprint is required and/or network bandwidth is at a premium (http://mqtt.org/).

The example is connected to a WinCC OA datapoint in system 1, sends incoming values through MQTT to HiveMQ (http://www.hivemq.com/try-out/, there is a public available MQTT broker for testing available). Another Java API Manager is subscribed to the MQTT broker, receives the values changes by MQTT and sets it to the WinCC OA system 2…