Setting this running, and varying the flow gives us some results in our database:
Noted that the first t_stamp here recorded is 1688125471633 = Friday, 30 June 2023 11:44:31.633 (GMT). This seems to not be correct as I am currently in GMT+1, and then +1 for the summertime (DST). I.e. Time now in DST is Friday, 30 June 2023 12:44:31.633 (GMT+2)
The result of this is seen when I try a tag history binding as only one data point comes back, and it is the first point of the table, but shown as 'in the future':
The database and gateway are all on the same VM - How do I fix this odd problem? Does the gateway have its own timezone somewhere thats incorrect? Or is it not correcting for daylight savings?
TLDR: Device OPC server time needs to be correct if using On Change.
Quick followup for anyone finding this!
After a chat with support it was found that the OPC server time in the PLC that it was drawing from was wrong. When using 'On Change', the historian now takes the timestamp from the OPC server. The ability to use the local timestamp when using 'On change' was removed as per the below from Colby Clegg.