eWON integrates 2 different types of logging:
- Realtime data logging
- Historical data logging
For both logging types, the eWON web interface allows to display the logged data in a table as well as on a graph.
The aim of the realtime logging is to record in RAM the Tag values on a short period . The realtime logging data is not stored on the eWON.
To activate the realtime logging of a Tag you need to specify a time span and a logging interval.
The Historical logging option can be enabled on each eWON Tag.
This logging can be performed either on value changes or based on a time interval.
On an eWON Flexy, you can store up to 900.000 points (depending on its memory configuration, default config = 250.000 points) .
The aim of the historical logging in the eWON is not to keep the historical data for years and years. Generally eWON is used to store the data locally and push the data to a central server every hour or once a day for example.
The Realtime logging and the Historical Logging can be retrieved in different formats using Export Block Descriptors (link to EBD).