The operator staff would like to get immediately informed by the machine regarding process productivity and plant availability. In case of degradation, the possible location or source of problem shall also be reported.

Every plant subsystem with OPC UA Server connectivity sends an event if a critical condition has been detected or a configured threshold has been reached. The subsystem can also contain IO-Link Master and Devices, where IO-Link Events are translated into OPC UA events. The reported events from these subsystems shall consist of:

• the origin identity of the event
• the unambiguous identity of the event
• the absolute time of occurrence according to the subsystems time base
• if the occurrence is temporal, the duration of the erroneous condition
• if possible, the identity of the processed item

On the application level, the following is derived on this raw data:

• an availability signal in traffic light encoding
• notification towards the operator staff