What type of timestamps does the Ewon Flexy use for its historical logging ?

ANSWER

As of firmware 13.2, the Ewon Flexy uses UTC timestamps to record its historical data internally (tag values and alarming). Before firmware 13.2, these devices used the local time to store historical data.

This eases the handling of data regardless where it comes from. But it can also have an impact on existing projects: Ewon Flexy or CD running a previous firmware would be using local time timestamps and others would be using UTC timestamps.

In terms of data logging, we see that it could be difficult to handle the backward compatibility.

UTC or local time timestamps?

As of firmware 13.2s0, we introduce the possibility to:

• continue using the local time as time reference.
• switch to the new model and start using in UTC.

The selection of the method how your Flexy handles the timestamps is based on a checkbox available in the System Wizard and in the settings of the date & time of your Flexy.

The default behavior of the firmware 13.2s0 is to continue exporting data in local time. Therefore, by default this checkbox is unchecked.

The choice to continue using local time or to switch to UTC timestamps would depend on your situation. Our recommendations are the following ones:

• Your Flexy is integrating a new project or is used as standalone => use UTC-based timestamps.
• Your Flexy is integrating or replacing another Ewon for an existing project => continue using local time.

We also created a KB-0284-00: UTC timestamp logging that explains how your Ewon behaves based on your choice.