# Parameter = tag from parent nested UDT

**URL:** <https://forum.inductiveautomation.com/t/parameter-tag-from-parent-nested-udt/77149>\
**Category:** Ignition\
**Tags:** ignition81\
**Created:** [July 31, 2023, 3:07pm UTC](https://forum.inductiveautomation.com/t/parameter-tag-from-parent-nested-udt/77149 "2023-07-31T15:07:22Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![rfolkes](https://avatars.discourse-cdn.com/v4/letter/r/e95f7d/32.png) [@rfolkes](https://forum.inductiveautomation.com/u/rfolkes)\
**Post date:** [July 31, 2023, 3:07pm UTC](https://forum.inductiveautomation.com/t/parameter-tag-from-parent-nested-udt/77149/1 "2023-07-31T15:07:22Z")

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See below for example. So what I would like to do is setup where the "Name" parameter of the Power udt is set to the value of the "name" tag within the parent UDT. I thought I could just do {[.]../Name} or {[.]../Info/Name} but that doesn't seem to work and I just get null value.

Nested UDTs getting values

abbreviated example

Power (UDT)  
Parameters - Name, plc, rack  
Tags - PS1ok, PS2ok, PS3ok, PS4ok

Rack (UDT)  
Parameters - plc, Rack  
Tags - Name, + a bunch more  
SubUDT - Power  
parametes name=??? PLC = {plc} Rack={Rack}

PLC (UDT  
Parameters - plc  
Tags Info/Name, + a bunch more  
Subudt - Power1  
parameters plc = {plc}, rack =0, name = ???  
Subudt - Power2  
parameters plc = {plc}, rack =0, name = ???  
Subudt - Rack1  
parameters plc={plc} Rack=1  
SubUDT - Rack2  
parameters plc={plc} Rack=2

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<div class="post-metadata">

**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:** [July 31, 2023, 3:31pm UTC](https://forum.inductiveautomation.com/t/parameter-tag-from-parent-nested-udt/77149/2 "2023-07-31T15:31:07Z")

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Parameter bindings aren't general purpose bindings. They only evaluate upon tag startup, and only have the tag's native properties and UDT parameters available as sources.

You will need a value change event script on the outer UDT's member tag and have it write to the inner UDT's parameter. (Or perhaps you might need `system.tag.configure()`.)

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<div class="post-metadata">

**Author:** ![rfolkes](https://avatars.discourse-cdn.com/v4/letter/r/e95f7d/32.png) [@rfolkes](https://forum.inductiveautomation.com/u/rfolkes)\
**Post date:** [July 31, 2023, 4:00pm UTC](https://forum.inductiveautomation.com/t/parameter-tag-from-parent-nested-udt/77149/3 "2023-07-31T16:00:47Z")

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> [@pturmel](#):
>
> lue change event script on t

Thanks, Was hoping there was a simpler way but just used the value changed script on the base tag.