# Historian keeps recording every second even though sample mode is On Change **URL:** \ **Category:** Ignition\ **Tags:** ignition81\ **Created:** [February 5, 2025, 7:15pm UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925 "2025-02-05T19:15:16Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Daniel\_Calderon](https://avatars.discourse-cdn.com/v4/letter/d/51bf81/32.png) [@Daniel\_Calderon](https://forum.inductiveautomation.com/u/Daniel_Calderon)\ **Post date:** [February 5, 2025, 7:15pm UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925/1 "2025-02-05T19:15:16Z")
Hi, Why would my OPC tag with history enabled get a sample every second if the value doesn't change? As long as I don't have Max Time Between Samples configured, I would not expect multiple samples with the same value. Is there anything I am missing? The table is populated with As Stored so there is not interpolation... ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/d/f/df6e8e01b27eec33385d15317d48dfc86a78fba4.png) ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/7/a/7a6f1d245dcb0e13601e0ab74288e369b3fecfc0.png) Thanks. Daniel. ---
**Author:** ![Transistor](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/transistor/32/3380_2.png) [@Transistor](https://forum.inductiveautomation.com/u/Transistor)\ **Post date:** [February 5, 2025, 7:30pm UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925/2 "2025-02-05T19:30:57Z")
> [@Daniel\_Calderon](#): > > As long as I don't have Max Time Between Samples configured, I would not expect multiple samples with the same value. ~~I think you _do_ have Max Time Between Samples configured. A value of zero is not "not configured". You've told it zero delay - so record the tag value at the polling rate, which I assume is _default_ and set to 1000 ms.~~ [This is incorrect. See Chris\_Bingham's docs reference in post #5 below.] Instead change it to a value that ensures you get at least one reading in every period of likely interest. This will avoid problems when you select a timespan when no changes were recorded. ---
**Author:** ![Steve\_Laubach](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/steve_laubach/32/60900_2.png) [@Steve\_Laubach](https://forum.inductiveautomation.com/u/Steve_Laubach)\ **Post date:** [February 5, 2025, 8:21pm UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925/3 "2025-02-05T20:21:53Z")
You can also get multiple collections of the same value if the OPC quality on the tag is changing. ---
**Author:** ![Daniel\_Calderon](https://avatars.discourse-cdn.com/v4/letter/d/51bf81/32.png) [@Daniel\_Calderon](https://forum.inductiveautomation.com/u/Daniel_Calderon)\ **Post date:** [February 5, 2025, 8:45pm UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925/4 "2025-02-05T20:45:35Z")
Thank you Transistor and Steve! Solved. You were both right. I didn't realize 0 does not mean "nothing" in Max Time Between Sample. And this was basically choking the OPC which kept changing quality from Good to Good Overload, and this also explains what Steve mentioned. It seems to be good now and I took Transistor's advice to have a Max time also to guarantee some data in the historian... ---
**Author:** ![Chris\_Bingham](https://avatars.discourse-cdn.com/v4/letter/c/e5b9ba/32.png) [@Chris\_Bingham](https://forum.inductiveautomation.com/u/Chris_Bingham)\ **Post date:** [February 6, 2025, 3:57am UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925/5 "2025-02-06T03:57:16Z")
From: [Tag Properties | Ignition User Manual](https://www.docs.inductiveautomation.com/docs/8.1/platform/tags/tag-properties#history-properties) > Max Time Between Samples > "Setting this value to 0 will disable automatic record collection. Default is 0." @Daniel_Calderon, what version of Ignition? What is the data type of the tag? What are the specifics of the tag group you are using? ---
**Author:** ![Transistor](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/transistor/32/3380_2.png) [@Transistor](https://forum.inductiveautomation.com/u/Transistor)\ **Post date:** [February 6, 2025, 9:16am UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925/6 "2025-02-06T09:16:24Z")
Thanks for the correction, Chris. I need to read it a few more times to see if I understand it now. ---
**Author:** ![Chris\_Bingham](https://avatars.discourse-cdn.com/v4/letter/c/e5b9ba/32.png) [@Chris\_Bingham](https://forum.inductiveautomation.com/u/Chris_Bingham)\ **Post date:** [February 6, 2025, 1:42pm UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925/7 "2025-02-06T13:42:32Z")
No problem. I still like your recommendation to set a reasonable value. 1/hour, 1/day…whatever makes sense to collect “as little data as possible for that point, but no less…” I suspect that @Steve_Laubach was correct, in that tag quality might be contributing excess data. > [@Daniel\_Calderon](#): > > changing quality from Good to Good Overload ^^^ @Daniel_Calderon - This is worth investigating further ^^^ Though, perhaps data type is a float, we’re not seeing the truncated data (additional decimal places), and compression settings (absolute @ 0.01) are working as expected? ---
**Author:** ![Daniel\_Calderon](https://avatars.discourse-cdn.com/v4/letter/d/51bf81/32.png) [@Daniel\_Calderon](https://forum.inductiveautomation.com/u/Daniel_Calderon)\ **Post date:** [February 6, 2025, 9:49pm UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925/8 "2025-02-06T21:49:21Z")
Chris thanks for the correction. Good to know. The type is integer and I moved them all to 10 sec poll rate and now they are always GOOD and not repeating values. I think root cause was quality status changing, [I saw an older post](https://forum.inductiveautomation.com/t/quality-change-cause-historian-log-tag-value/41189) I am running 8.1.45. ---
**Author:** ![aholmes03](https://avatars.discourse-cdn.com/v4/letter/a/9fc29f/32.png) [@aholmes03](https://forum.inductiveautomation.com/u/aholmes03)\ **Post date:** [October 22, 2025, 5:31pm UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925/9 "2025-10-22T17:31:27Z")
Where do you set the polling rate to 10 seconds? @Daniel_Calderon ---
**Author:** ![robertm](https://avatars.discourse-cdn.com/v4/letter/r/ea5d25/32.png) [@robertm](https://forum.inductiveautomation.com/u/robertm)\ **Post date:** [October 22, 2025, 9:55pm UTC](https://forum.inductiveautomation.com/t/historian-keeps-recording-every-second-even-though-sample-mode-is-on-change/101925/10 "2025-10-22T21:55:25Z")
Tag poll rates are set in the Tag Group configuration for each Tag Provider.