# Pens disappears from the PowerChart after linking its source with indirection binding

**URL:** <https://forum.inductiveautomation.com/t/pens-disappears-from-the-powerchart-after-linking-its-source-with-indirection-binding/59611>\
**Category:** Ignition\
**Tags:** perspective, ignition81\
**Created:** [May 16, 2022, 1:47pm UTC](https://forum.inductiveautomation.com/t/pens-disappears-from-the-powerchart-after-linking-its-source-with-indirection-binding/59611 "2022-05-16T13:47:21Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![Ahad\_Imtiaz](https://avatars.discourse-cdn.com/v4/letter/a/6de8d8/32.png) [@Ahad\_Imtiaz](https://forum.inductiveautomation.com/u/Ahad_Imtiaz)\
**Post date:** [May 16, 2022, 1:47pm UTC](https://forum.inductiveautomation.com/t/pens-disappears-from-the-powerchart-after-linking-its-source-with-indirection-binding/59611/1 "2022-05-16T13:47:21Z")

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Hi Community,  
I am facing an issue with the indirection of power charts. I want to add dynamic tag bindings to my power chart. Here I am sharing the steps with screenshots that I am following.

Step 1:  
Selecting the status tag (sts) in the tag browser of power chart.

 ![step1](https://us1.discourse-cdn.com/inductiveautomation/original/3X/a/3/a3f2abfee1805db8f1f17511e7e51c1dc5bdb704.png)

Pen appears with the source:  
histprov:IgnitionDB01:/drv:kl\_cj2:/tag:vdc\_kl\_testinstances/cb/status/sts

 ![step2](https://us1.discourse-cdn.com/inductiveautomation/original/3X/1/4/140e4af97ef857f829edb007046d95a3c7050f75.png)

Step 2:  
Now I use expression of indirection binding. There is no error in the binding as it can be seen in the image below. view.params.tagPath value is VDC\_KL\_TestInstances/CB

 ![step3](https://us1.discourse-cdn.com/inductiveautomation/original/3X/2/c/2c7f2a8c016027d42682ce256266ac055cbbd5bf.png)

Step 3:  
But when I press apply and ok, the pen disappears and not even showing in the perspective launcher.

 ![Step4](https://us1.discourse-cdn.com/inductiveautomation/original/3X/9/4/94bd282f7cac98b0e7b0792be52020d73d132040.png)

What is the issue here?

Hope to hear from you all soon.

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<div class="post-metadata">

**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:** [May 16, 2022, 1:54pm UTC](https://forum.inductiveautomation.com/t/pens-disappears-from-the-powerchart-after-linking-its-source-with-indirection-binding/59611/2 "2022-05-16T13:54:14Z")

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What is the value of `view.params.tagPath`, my guess is that it isn’t what you think it is in the designer.

Have you tried this in a browser?

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<div class="post-metadata">

**Author:** ![Ahad\_Imtiaz](https://avatars.discourse-cdn.com/v4/letter/a/6de8d8/32.png) [@Ahad\_Imtiaz](https://forum.inductiveautomation.com/u/Ahad_Imtiaz)\
**Post date:** [May 16, 2022, 2:04pm UTC](https://forum.inductiveautomation.com/t/pens-disappears-from-the-powerchart-after-linking-its-source-with-indirection-binding/59611/3 "2022-05-16T14:04:03Z")

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![2022_05_16_19_01_43_Films_TV](https://us1.discourse-cdn.com/inductiveautomation/original/3X/b/6/b6ebc1b7419c2526190a383832679f78e4760fea.png)

view.params.tagPath value is VDC\_KL\_TestInstances/CB

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<div class="post-metadata">

**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:** [May 16, 2022, 2:08pm UTC](https://forum.inductiveautomation.com/t/pens-disappears-from-the-powerchart-after-linking-its-source-with-indirection-binding/59611/4 "2022-05-16T14:08:24Z")

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I think that the case matters.

Try this for the expression:

```auto
"histprov:IgnitionDB01:/drv:kl_cj2:/tag:" + lower({view.params.tagPath}) + "/status/sts"

```

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<div class="post-metadata">

**Author:** ![Ahad\_Imtiaz](https://avatars.discourse-cdn.com/v4/letter/a/6de8d8/32.png) [@Ahad\_Imtiaz](https://forum.inductiveautomation.com/u/Ahad_Imtiaz)\
**Post date:** [May 16, 2022, 2:16pm UTC](https://forum.inductiveautomation.com/t/pens-disappears-from-the-powerchart-after-linking-its-source-with-indirection-binding/59611/5 "2022-05-16T14:16:46Z")

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I tried this before but didn’t worked in browser. On perspective launcher, pen doesn’t shown.

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/a/3/a3ad7e08edb798d620b66ff9dbdc472ae9060df5.png)

Only seen in designer not in launcher

 ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/0/2/0287d4036b9c8cf2b9500be384394fa5cf2d1875.png)

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<div class="post-metadata">

**Author:** ![Ahad\_Imtiaz](https://avatars.discourse-cdn.com/v4/letter/a/6de8d8/32.png) [@Ahad\_Imtiaz](https://forum.inductiveautomation.com/u/Ahad_Imtiaz)\
**Post date:** [May 18, 2022, 7:06am UTC](https://forum.inductiveautomation.com/t/pens-disappears-from-the-powerchart-after-linking-its-source-with-indirection-binding/59611/6 "2022-05-18T07:06:24Z")

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Adding an expression binding in data/source like this resolves the issue.

lower({view.params.tagPath}) + “/system/sts”

No need to enter like this:  
“histprov:IgnitionDB01:/drv:kl\_cj2:/tag:” + lower({view.params.tagPath}) + “/status/sts”