Electricity + Control 2019

CONTROL SYSTEMS + AUTOMATION

Sensor technology in the age of Industry 4.0 Integrating information from sensor to data platform Sensors are already delivering a lot more than just data. Additional data can be transferred onto platforms using the correct interfaces and protocols. By using appropriate interfaces, communication components and semantic agreements, all sensor data can be made available in cloud systems or local data platforms so it can be processed even without detailed knowledge of the transmission technology, thus abstracting the communication channel. Benedikt Rauscher, Leader of Global Industry 4.0 Projects, Pepperl + Fuchs

1. Sensors are in effect the sensory organs of machines and plants and are keystones in Industry 4.0 scenarios. Take Note! 1

S ensors convert physical effects into elec- trical values and make them available for further processing. They are in effect the sensory organs of machines and plants and are keystones in Industry 4.0 scenarios. In addition to pure data, sensors deliver a large amount of valuable data about their identity or their condition, for example. It is also possible to use parameter sets to adapt the sensors perfectly to different applications. Bidirectional interfaces and protocols are need- ed to transfer these parameters to the sensors and receive data from them. The interfaces and protocols must follow the applicable standards strictly so that products from different manufac- turers can be used without any issues. IO-Link has established itself as the interface of choice for ‘the final centimetres’ in sensor technology; Ethernet-based technologies such as EtherCAT, PROFINET and EtherNet/IP, among others, are also used for more complex units. Pepperl+Fuchs uses the trademarked term Sensorik4.0 ® for its portfolio of products that have been designed in line with this concept and equipped accordingly.

When sensor data is being evaluated, applica- tions for data processing in closed control loops have to be considered separately. There are often tough real-time demands in such scenarios, mean- ing that appropriate PLC hardware needs to be used in conjunction with communication channels that perform efficiently. The processing of all other data supplied by sensors is generally not time-sensitive, but this data must be recorded, stored and processed over longer periods of time. In addition to those for signal transmission, par- allel data paths to data platforms are constructed. So-called edge gateways are used for this pur- pose. Edge gateways communicate with sensors and actuators via control modules and PLCs while also establishing connections to data platforms. This is done using protocols that support publish/ subscribe mechanisms such as MQTT, AMQP, or OPC/UA with publish/subscribe extension. A data platform can be operated on a plant oper- ator's local network or as an online cloud solution. These platforms feature databases for structured storage of sensor data and provide interfaces that allow various applications to access the data.

6 Electricity + Control

JUNE 2019