# \[13069\] - Write value to Opc item feature for Expression Tags is no longer available in 8.0 **URL:** \ **Category:** Ignition Early Access\ **Created:** [March 7, 2019, 8:44am UTC](https://forum.inductiveautomation.com/t/13069-write-value-to-opc-item-feature-for-expression-tags-is-no-longer-available-in-8-0/23112 "2019-03-07T08:44:59Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![andrea.morando](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/andrea.morando/32/8039_2.png) [@andrea.morando](https://forum.inductiveautomation.com/u/andrea.morando)\ **Post date:** [March 7, 2019, 8:44am UTC](https://forum.inductiveautomation.com/t/13069-write-value-to-opc-item-feature-for-expression-tags-is-no-longer-available-in-8-0/23112/1 "2019-03-07T08:44:59Z")
Dear all, in the 7.9.x releases, I was used to use the “Write value back to OPC item” feature for Expression Tags. ![07-03-2019%2009-39-59](https://us1.discourse-cdn.com/inductiveautomation/original/2X/1/1f487fe1452dac0e615713b869b47ec64791ef22.png) Where do I find this feature in the new tag environment? Thank you. ---
**Author:** ![anjoroge](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/anjoroge/32/6698_2.png) [@anjoroge](https://forum.inductiveautomation.com/u/anjoroge)\ **Post date:** [March 11, 2019, 3:49pm UTC](https://forum.inductiveautomation.com/t/13069-write-value-to-opc-item-feature-for-expression-tags-is-no-longer-available-in-8-0/23112/2 "2019-03-11T15:49:24Z")
Hi Andrea.morando Unfortunately there is no way to give you an answer on whether or not this feature will be included in 8.0 and is under management review. I Will write a feature ticket request for it and keep you updated on what the decisions have been made about it. Thanks, Anthony ---
**Author:** ![awalker](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/awalker/32/6874_2.png) [@awalker](https://forum.inductiveautomation.com/u/awalker)\ **Post date:** [March 29, 2019, 4:56pm UTC](https://forum.inductiveautomation.com/t/13069-write-value-to-opc-item-feature-for-expression-tags-is-no-longer-available-in-8-0/23112/3 "2019-03-29T16:56:56Z")
This issue was fixed in the build that was uploaded today (3/29). Please let us know if you continue to see this behavior after upgrading. ---
**Author:** ![andrea.morando](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/andrea.morando/32/8039_2.png) [@andrea.morando](https://forum.inductiveautomation.com/u/andrea.morando)\ **Post date:** [May 11, 2019, 12:51pm UTC](https://forum.inductiveautomation.com/t/13069-write-value-to-opc-item-feature-for-expression-tags-is-no-longer-available-in-8-0/23112/4 "2019-05-11T12:51:47Z")
Dears, I am currently using the 8.0.1 release. Actually I did not find this feature in the expression tags. Could you clarify me better? Thanks. ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [May 11, 2019, 1:20pm UTC](https://forum.inductiveautomation.com/t/13069-write-value-to-opc-item-feature-for-expression-tags-is-no-longer-available-in-8-0/23112/5 "2019-05-11T13:20:28Z")
This functionality as it was in 7.9 is not coming back. Tags that had an OPC write-back defined now get a special “Legacy Value Changed” entry in the Tag Event Scripts: ![wb_script](https://us1.discourse-cdn.com/inductiveautomation/original/2X/3/315a80cd3f1d2dddb36e997a9e542fe499d0db97.png) Tags that you want to add this functionality to should just use the regular Value Changed event to invoke `system.opc.writeValue`. ---
**Author:** ![andrea.morando](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/andrea.morando/32/8039_2.png) [@andrea.morando](https://forum.inductiveautomation.com/u/andrea.morando)\ **Post date:** [May 11, 2019, 2:14pm UTC](https://forum.inductiveautomation.com/t/13069-write-value-to-opc-item-feature-for-expression-tags-is-no-longer-available-in-8-0/23112/6 "2019-05-11T14:14:31Z")
Ok, that’s clear. Thank you again. Best, Andrea ---
**Author:** ![fares](https://avatars.discourse-cdn.com/v4/letter/f/71e660/32.png) [@fares](https://forum.inductiveautomation.com/u/fares)\ **Post date:** [June 27, 2019, 5:52pm UTC](https://forum.inductiveautomation.com/t/13069-write-value-to-opc-item-feature-for-expression-tags-is-no-longer-available-in-8-0/23112/7 "2019-06-27T17:52:36Z")
Hi Kevin, It seems that the “Legacy Value Changed” is missing. I’m in 8.0.2. I tried the followin code in “Value changed” but does not work. The opc object is a vector and the value is a 1 column dataset… ``` system.opc.writeValue('c100','ns=3;s="db_l2"."param"."values"',currentValue.value) ``` Thank you very much Federico ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [June 27, 2019, 6:03pm UTC](https://forum.inductiveautomation.com/t/13069-write-value-to-opc-item-feature-for-expression-tags-is-no-longer-available-in-8-0/23112/8 "2019-06-27T18:03:48Z")
“Legacy Value Change” was something that would only appear on upgrades after the fix was added. Adding a new one to Value Changed is the right place… You can’t write a dataset to OPC, you’ll need to pull the scalar value you want to write out of the dataset first. ---
**Author:** ![fares](https://avatars.discourse-cdn.com/v4/letter/f/71e660/32.png) [@fares](https://forum.inductiveautomation.com/u/fares)\ **Post date:** [July 1, 2019, 1:12pm UTC](https://forum.inductiveautomation.com/t/13069-write-value-to-opc-item-feature-for-expression-tags-is-no-longer-available-in-8-0/23112/9 "2019-07-01T13:12:36Z")
Al working ok now. Thank you very much for your help!