How to set the Timestamp Source to Value on a tag

How to set the Timestamp Source to Value on a tag, this option is available in Ignition 7.9 but I can not find how to do this using Ignition 8.

I need this option because alarm bits are timestamped by the PLC in our projects.

Kind regards,

There should be a Timestamp Source property for each Alarm defined on a tag.

I know, but that is on the alarm and not on the tag itself, see screen shot (source ignition 7.9).

Well, that’s a history-related setting, not the tag itself.

There’s 2 timestamps that might come with a value from an OPC server - “source” and “server”. OPC tags always get the “source” timestamp if defined and the “server” timestamp if not. Usually it’s the “server” timestamp, which in the common case with e.g. a polling-based driver is the timestamp at which it polled the value. “Source” timestamps are only used when there’s a possibility the device will send a timestamp along with a value.

Ok, I meant the history-related setting.

We use an additional OPC OFS of Schneider Electric for timestamped events, which is capable of sending the timestamp along with a value. This works perfectly for the alarm, but of course we would like to write the event to history with the same timestamp, so this state change can be use in graphs with together with other signals.

So still I can not find the setting in Ignition 8!

I’m not sure exactly how this works in 8 or what the equivalent is for history. I’ll have to ask around in a couple hours when more people are in the office.

any news about this item?


Sorry for the delay- this setting was removed in 8 in an effort to start to reduce the multiple layers of timing definition and to get down to single sources of data.

The system timestamp only makes sense in situations where the system is scanning tags to collect values. In cases where the values are coming from the sources and being evaluated as they change, it makes sense to use the source timestamp.

So, we’ve made the logic that was previous driven by this setting more implicit. If the history is being collected “on change”, the value timestamp will be used. If the history mode is “tag group” or “periodic”, the system timestamp will be used.

I hope this helps. We’re open to refining the settings a bit more if necessary, and will be doing a little more work on tag history soon (for example, identifying and separating server-generated bad quality events from other quality events that come from the device).

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the OPCDA server we have hooked up to ignition, TDS32 from ABB, exports TAGNAME and TAGNAME_TS on every value to provide an explicit timestamp on that tag. We need this for volume calculation tags so that we have the correct timestamp on the volume. It has nothing to do with when the value was polled, it comes from the device and is the timestamp on the calculation event. It has to be possible to combine these two tags into a tag with the value and the provided timestamp.

Hi!I am facing a problem of timestamp mismatch.The tag value is getting logged at a different time stamp in the historian but not the exact time at which it got executed.For instance if my tag’s last execution was at around 11:15 pm , the value corresponding to 11:15 pm is getting logged at 11:20 pm in my historian.Why is this happening?Is there any solution to this?Kindly help me out.
Tag Setting:
Sample mode : Periodic
Min time between samples :5 min
Max time between samples : 5 min (I want to log data for every five minutes)
The tag group base rate is also 5 minutes

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