# Add a timer before a tag get changed **URL:** \ **Category:** Ignition\ **Created:** [August 27, 2024, 9:50am UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194 "2024-08-27T09:50:10Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![Odd-Simon\_Simonsen](https://avatars.discourse-cdn.com/v4/letter/o/a88e4f/32.png) [@Odd-Simon\_Simonsen](https://forum.inductiveautomation.com/u/Odd-Simon_Simonsen)\ **Post date:** [August 27, 2024, 9:50am UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/1 "2024-08-27T09:50:10Z")
Hello, Is it possible to add an timer on the scripting menu on a tag? I have an numeric label for the process value "PV", and an numering label for an setpoint "SP". When the PV goes over the setpoint SP i have it automaticly pressing a One Shot Button trough scripting. But I dont want it to be pressed right away, I want it to wait a few seconds before pressing the One Shot Button. Is there possible to add a timer in the scripting menu of the PV? Thanks ---
**Author:** ![nminchin](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/nminchin/32/6911_2.png) [@nminchin](https://forum.inductiveautomation.com/u/nminchin)\ **Post date:** [August 27, 2024, 11:40am UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/2 "2024-08-27T11:40:38Z")
Sounds like something that should be implemented in the plc.. Or, look at this > [@Best way to trigger a script after a time delay without pausing a script](https://forum.inductiveautomation.com/t/best-way-to-trigger-a-script-after-a-time-delay-without-pausing-a-script/89638/15): > > Welcome to the world of non-deterministic operating systems. slight_smile I was able to get a bit better performance by not running it through the alarm subsystem. [UDT\_Timer\_millis.json](https://forum.inductiveautomation.com/uploads/short-url/nWcXZBz8Ponvt3lJJBLQjnw6M3h.json) (2.1 KB) ---
**Author:** ![lrose](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/lrose/32/62724_2.png) [@lrose](https://forum.inductiveautomation.com/u/lrose)\ **Post date:** [August 27, 2024, 12:31pm UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/3 "2024-08-27T12:31:46Z")
> [@Odd-Simon\_Simonsen](#): > > Is there possible to add a timer in the scripting menu of the PV? Place your script in a function and use `system.util.invokeLater()` with the desired delay. > **[system.util.invokeLater | Ignition User Manual](https://www.docs.inductiveautomation.com/docs/8.1/appendix/scripting-functions/system-util/system-util-invokeLater)** > > Invokes (calls) the given Python function object after all of the currently processing and pending events are done being processed, or after a specified delay. ---
**Author:** ![Odd-Simon\_Simonsen](https://avatars.discourse-cdn.com/v4/letter/o/a88e4f/32.png) [@Odd-Simon\_Simonsen](https://forum.inductiveautomation.com/u/Odd-Simon_Simonsen)\ **Post date:** [August 27, 2024, 12:44pm UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/5 "2024-08-27T12:44:32Z")
> [@lrose](#): > > Place your script in a function and use `system.util.invokeLater()` with the desired delay. I tried this, but if the PV changes back down under the SP value it still pushes down the button after the delay ---
**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:** [August 27, 2024, 12:46pm UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/6 "2024-08-27T12:46:55Z")
You will not find a **robust** solution that runs in the user interface. You need repeating **gateway** logic that examines your conditions, sets timestamps, and acts upon past timestamps. Just like a PLC would. ---
**Author:** ![Odd-Simon\_Simonsen](https://avatars.discourse-cdn.com/v4/letter/o/a88e4f/32.png) [@Odd-Simon\_Simonsen](https://forum.inductiveautomation.com/u/Odd-Simon_Simonsen)\ **Post date:** [August 27, 2024, 12:49pm UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/7 "2024-08-27T12:49:42Z")
Is it possible to script the value of the button to 1 after the alarmEvent.state.isActive goes true? then I can use the alarm active delay to push the button iguess? ---
**Author:** ![lrose](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/lrose/32/62724_2.png) [@lrose](https://forum.inductiveautomation.com/u/lrose)\ **Post date:** [August 27, 2024, 1:00pm UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/8 "2024-08-27T13:00:01Z")
> [@Odd-Simon\_Simonsen](#): > > I tried this, but if the PV changes back down under the SP value it still pushes down the button after the delay Your function needs to re-examine the conditions then. As @pturmel said using the UI to do this isn’t going to be robust. You can get close but there will be unhandled cases. ---
**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:** [August 27, 2024, 1:18pm UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/9 "2024-08-27T13:18:59Z")
> [@lrose](#): > > be unhandled cases. Like, what do you want to happen when no client is open? Or not open to the window with that button? Or with a modal notification up that stops your scripts? Or when you have more than one client open? Really, this is not a task for your user interface. ---
**Author:** ![amarks](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/amarks/32/45610_2.png) [@amarks](https://forum.inductiveautomation.com/u/amarks)\ **Post date:** [August 27, 2024, 8:23pm UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/10 "2024-08-27T20:23:00Z")
This is absoluetly something that should be done in the PLC. Here's my 2¢: You'll want a UDT to organize everything. 1. OPC tag for the SP `Process_SP` 2. OPC tag for the PV `Process_PV` 3. Memory tag for the button-press delay `Auto_Adj_PRE` 4. Expression tag to detect when the PV exceeds the SP `Auto_Adj_Req` [`{Process_PV} > {Process_SP}`] 5. Memory tag used as intermediary before actually executing the update button `Auto_Adj_INT` 6. OPC tag for the button `Update_SP_PB` 2 different `valueChange` scripts should get the job done here. 1. `Auto_Adj_INT.valueChaged()` ```python def valueChanged(): if currentValue != previousValue and not initialChange: if currentValue.value == 2: system.tag.writeBlocking(['Update_SP_PB'], ['1']) #psuedo-path ``` 1. `Auto_Adj_Req.valueChanged()` ```python def valueChanged(): if currentValue != previousValue and not initialChange: #PV > SP if currentValue.value: #get the delay delay = system.tag.readBlocking(['Auto_Adj_INT'])[0].value #psuedo-path system.util.invokeLater(maybeUpdate, delay) #PV < SP else: #reset INT to 0 - cancels the PB system.tag.writeBlocking(['Auto_Adj_INT'], [0]) #psuedo-path def maybeUpdate(): #read current INT autoAdjINT = system.tag.readBlocking(['Auto_Adj_INT'])[0].value #psuedo-path #INT is still 1, update to 2 - triggering the INT's valueChanged script if autoAdjINT == 1: system.tag.writeBlocking(['Auto_Adj_INT'], [2]) #psuedo-path ``` Again, way easier in the PLC. Also, I am unsure if your oneshot button exists in the GUI or in the PLC, or how it gets reset ---
**Author:** ![amarks](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/amarks/32/45610_2.png) [@amarks](https://forum.inductiveautomation.com/u/amarks)\ **Post date:** [August 27, 2024, 8:24pm UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/11 "2024-08-27T20:24:45Z")
@Odd-Simon_Simonsen did not specify if this is a one-shot button on the GUI or in the PLC. I assumed that it was a button in the PLC. ---
**Author:** ![michael.flagler](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/michael.flagler/32/26272_2.png) [@michael.flagler](https://forum.inductiveautomation.com/u/michael.flagler)\ **Post date:** [August 27, 2024, 8:27pm UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/12 "2024-08-27T20:27:25Z")
What exactly are you trying to accomplish? I think if you described what the end goal was, it would help everyone understand what you're doing. What is the function of the one-shot button? Is it tied to a PLC tag? Are you running a script to do something else? While ideally this is something done in the PLC, if it's doing something in Ignition or a DB, or something else, sharing that information would help everyone else out. ---
**Author:** ![Odd-Simon\_Simonsen](https://avatars.discourse-cdn.com/v4/letter/o/a88e4f/32.png) [@Odd-Simon\_Simonsen](https://forum.inductiveautomation.com/u/Odd-Simon_Simonsen)\ **Post date:** [August 28, 2024, 5:41am UTC](https://forum.inductiveautomation.com/t/add-a-timer-before-a-tag-get-changed/95194/13 "2024-08-28T05:41:21Z")
Thanks everyone by your input. And sorry if what I tried to explain/ask for was very unclear. I ended up setting up an alarm for the process value PV rising over the setpoint SP, this with the . And with this i added the Active delay property on the alarm. I then went on the scripting on the same tag, with the Alarm Events \> Alarm Active. Wrote what thag to be changed to 1/TRUE when the alarm is active: system.tag.writeBlocking(TagPath, 1) This ended up working and did what I tried to accomplish without changing the PLC code (due to old PLC and dont want to edit code thats havent been touched in years).