Glossary · Data, timing and communication
Timestamp
Also known as: time stamp
German: Zeitstempel
In systems engineering, a timestamp is the recorded time associated with an event, value, command or state. It states when something happened or was measured, which is not necessarily when it was received.
- Data and interfaces
- Integrated systems
In one sentence
A timestamp records when an event, value, command or state occurred; without a defined time source and meaning, it misleads more than it helps.
Example
A drive fault on a CNC machine is logged with the time the drive detected it, not the later time at which the MES received the message.
How it applies
- Integrated systems: Specify which moment a timestamp represents (measurement, event detection, sending or receipt), its resolution, time zone and time source. Two systems with different conventions produce contradictory event sequences.
- Functional safety: Timestamps are how consumers detect stale data. They are only trustworthy with time synchronization.
- Evidence: Timestamps make records in an audit trail and in change histories verifiable. Use ISO 8601 with a UTC offset in exported records.
- Technical documentation: Document versions and review dates are timestamps too; they show readers whether information is current.