Issue
What happens to an alarm message when local time shifts due to daylight saving changes (e.g., clocks moving back or forward)?
Product Line
Satchwell BAS & Sigma, Satchwell MicroNet, TAC VistaEnvironment
Remote Alarm Manager
Cause
This issue relates to how RAM handles time changes on the host PC. If an alarm is triggered before the time change and cleared after the system clock has shifted (e.g., moved back one hour), it may result in inconsistencies in how the alarm timestamps are displayed.
Scenario Example
- An alarm is triggered at 15:46 local time.
- The system clock is manually adjusted back by one hour (e.g., due to daylight saving ending).
- The alarm is cleared at 14:52 (which is technically before the original alarm time).
- RAM logs show the alarm raised at 15:46 and cleared at 14:52.
- However, in the alarm properties, the cleared time may incorrectly display as 15:52, due to how the system reconciles time changes.
Resolution
Testing confirms that RAM handles this scenario without functional issues. Although timestamp discrepancies may appear temporarily in the alarm properties, the system normalizes once the time progresses past the original alarm time. This ensures accurate historical logging and alarm status.
