Fixing a 5-Hour OPC Timestamp Offset (PLC to Ignition)

Ignition
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I am experiencing a 5-hour time sync issue between a B&R PLC and an Ignition Perspective Gateway. Initially, a specific "Trigger Timestamp" tag was showing a 5-hour offset. To "fix" this, the HMI clock on the PLC was manually adjusted by 5 hours. While this made that specific tag value look correct, all other tags being logged to the Historian and plotted on XY Charts are now 5 hours off.

Im assuming this is because the timestamp from OPC is still using the PLC actual time no the offset set by the HMI. The problem is I have no other way of access to the PLC program. Is there a way to adjust this within Ignition perspective or the gateway?

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It means the B&R PLC's OPC server is violating the OPC standard. Timestamps in OPC are UTC on the wire, no matter what local timezone is in effect.

For such broken PLCs, the only maintainable solution is to set the PLC itself to UTC.

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i had a similar issue with this. Changing all of the timezones became an issue.
my fix was an expression binding on the time i was using.

addHours(now(0), -5) change that -5 to +5 if you need to, it made it easier for my XYchart to give the correct times.

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I'm not sure how your "Trigger Timestamp" tag is configured. If its value is being read from the PLC, I'm not sure why the timestamp for that has a different offset than the other tags on the PLC. Are you reading the value of that tag differently than you are the other tags?

In 8.3, you can configure the preferred timestamp source, which may or may not be useful depending on how much you care about the source timestamp. OPC UA Connections | Ignition User Manual