Ignition Edge tags recording "Good_Overload" quality, filling historian

[liam1]

Hi all,

Setup:

Ignition Edge 3.8.7 with the latest OPC-UA module
Gateway Ram: 4GB
PLC: Siemens S7-1500
387 tags historized total, 40 of which are analog

Total Monitored OPC tags: 4856

Issue:
We noticed history for our analog tags was only being retained for a maximum of ~24 hours. Given the tag count and our historian settings, this retention window didn't add up.

On further investigation, we found the historian was filling up because a large number of records were being logged with Good_Overload (202) quality instead of normal Good quality.

What we've tried:

Increased tag group execution rates/intervals
Widened deadband margins on the analog tags

Neither change stopped the Good_Overload records from being logged.

What's confusing us:

Gateway logs show nothing indicating an overload
OPC-UA connection/diagnostics show no signs of overload either

Question:
What else could cause tags to persistently report Good_Overload quality when there's no visible overload in the logs or diagnostics? Is there another setting (subscription queue size, publishing interval, sampling interval, buffer size on the OPC-UA server side) we should be checking?

On Boolean tags with onChange set, we noticed data was being store but the value was not changing only the quality.

[JordanCClark]

Good_Overload results in excessive historian logging

Hi, We are experiencing troubles with a customer that has excessive historian logging. I suspect the main reason are some tags who flip to Good_Overload("Sampling has slowed down due to resource limitations.") Quality and then back to GOOD quality. I suspect this issues a historian change and makes the historian log this in our database. Strangly enough the log entry has status code 192. Is there a way to avoid this excessive logging? Thank you, Thijs Ignition Platform 8.1.12

[pturmel]

TL/DR: This is coming from your Siemens PLC. "Fixing the overload" means "Get a more powerful model, or reduce the quantity/pace of the tags you are monitoring".

[liam1]

Changing the Comminication load on the plc from 20% to 50% seems to have fixed it.

[Kevin.Herron]

For future reference, changing the Tag Group rate is normally the way to change the sampling interval of OPC tags / monitored items belonging to that group, but you have overridden the defaults and provided explicit publishing and sampling intervals in your group OPC UA settings, so you would need to change those instead.