# Transaction group OPC data mode

**URL:** <https://forum.inductiveautomation.com/t/transaction-group-opc-data-mode/17517>\
**Category:** Ignition\
**Created:** [March 27, 2018, 9:11am UTC](https://forum.inductiveautomation.com/t/transaction-group-opc-data-mode/17517 "2018-03-27T09:11:38Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Claus\_Nielsen](https://avatars.discourse-cdn.com/v4/letter/c/77aa72/32.png) [@Claus\_Nielsen](https://forum.inductiveautomation.com/u/Claus_Nielsen)\
**Post date:** [March 27, 2018, 9:11am UTC](https://forum.inductiveautomation.com/t/transaction-group-opc-data-mode/17517/1 "2018-03-27T09:11:38Z")

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Does someone know if it’s correct when my tests seems to indicate that when the ‘OPC data mode’ is set to ‘Read’ it only updates when the groups trigger is true? The documentation says it will perform a read every execution, however it seems like that even though the ‘Last Execution’ time updates, the OPC values doesn’t.

Just need to be sure as my tests gives the desired result, just don’t want the OPC items to read on every execution where the trigger is false.

Also, a little feature request to the IA people here, having custom properties on the folders would be awesome!

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**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [March 27, 2018, 1:10pm UTC](https://forum.inductiveautomation.com/t/transaction-group-opc-data-mode/17517/2 "2018-03-27T13:10:58Z")

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OPC Read mode subscribes to the trigger, and executes only the always-run items every time. The rest of the items are only read from the OPC server when the trigger is true. This is the correct (only non-script) method of implementing value snapshots after a trigger.