Scheduled event runs only on the hour instead of every 15 minutes

The following scheduled event should run at :00, :15, :30 and :45 past the hour.

The 0/15 configuration seems to be interpreted correctly as shown in the Preview.
The script writes to a data table and I can see that it has executed at 11:00, 12:00, 13:00, etc.

Can anyone suggest why this doesn’t work as expected?

Try using */15 instead

Actually try using 0,15,30,45

Done at 3 minutes to the hour. I’ll report back in 20 minutes or so.
I liked the look of the 0/15 as it implied starting on the hour but I can see that all it can do is return a zero so it only triggers on the hour.

I had tried 0,15,30,45 * * * * but wasn’t happy that Ignition understood it.

The */15 seems to have triggered correctly at 14:00:00. Let’s see at 14:15 (Irish time).

The preview validator is a bit simplistic and seems to allow patterns that are actually parsed differently, unfortunately.

Compare:
https://crontab.guru/#/15_*_
https://crontab.guru/#0/15__**
Note that the latter warns:
Non standard! May not work with every cron.

I’m running now with
0,15,30,45 * * * *

It seems to be working, it’s unambiguous and it’s definitely on the quarter hour.

Thank you all.

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