# Is there an upper limit to the tags that can be read with system.opc.readValue?

**URL:** <https://forum.inductiveautomation.com/t/is-there-an-upper-limit-to-the-tags-that-can-be-read-with-system-opc-readvalue/52790>\
**Category:** Ignition\
**Tags:** ignition80, vision, scripting\
**Created:** [November 5, 2021, 6:35pm UTC](https://forum.inductiveautomation.com/t/is-there-an-upper-limit-to-the-tags-that-can-be-read-with-system-opc-readvalue/52790 "2021-11-05T18:35:52Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![bmeyers](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bmeyers/32/37453_2.png) [@bmeyers](https://forum.inductiveautomation.com/u/bmeyers)\
**Post date:** [November 5, 2021, 6:35pm UTC](https://forum.inductiveautomation.com/t/is-there-an-upper-limit-to-the-tags-that-can-be-read-with-system-opc-readvalue/52790/1 "2021-11-05T18:35:52Z")

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I am trying to read 11,000 tags using system.opc.readValue but only can grab 1000 or so. What is the deal?

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**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:** [November 5, 2021, 6:42pm UTC](https://forum.inductiveautomation.com/t/is-there-an-upper-limit-to-the-tags-that-can-be-read-with-system-opc-readvalue/52790/2 "2021-11-05T18:42:46Z")

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How does it fail?

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**Author:** ![bmeyers](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bmeyers/32/37453_2.png) [@bmeyers](https://forum.inductiveautomation.com/u/bmeyers)\
**Post date:** [November 5, 2021, 6:46pm UTC](https://forum.inductiveautomation.com/t/is-there-an-upper-limit-to-the-tags-that-can-be-read-with-system-opc-readvalue/52790/3 "2021-11-05T18:46:57Z")

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It doesn’t. I think the following is actually failing:

```auto
#convert dataset into user chosen csv.
csv = system.dataset.toCSV(ds, showHeaders=True, forExport=False)
filePath = system.file.openFile('*.csv')
system.file.writeFile(filePath, csv)
```

I can only save 1082 rows. Thoughts?

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<div class="post-metadata">

**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:** [November 5, 2021, 6:49pm UTC](https://forum.inductiveautomation.com/t/is-there-an-upper-limit-to-the-tags-that-can-be-read-with-system-opc-readvalue/52790/4 "2021-11-05T18:49:15Z")

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How does it fail? Error? Only 1082 rows show up in the file?

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<div class="post-metadata">

**Author:** ![bmeyers](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bmeyers/32/37453_2.png) [@bmeyers](https://forum.inductiveautomation.com/u/bmeyers)\
**Post date:** [November 5, 2021, 6:49pm UTC](https://forum.inductiveautomation.com/t/is-there-an-upper-limit-to-the-tags-that-can-be-read-with-system-opc-readvalue/52790/5 "2021-11-05T18:49:51Z")

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No errors. Only 1082 rows appear in excel from the dataset over 10,000 rows.

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<div class="post-metadata">

**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:** [November 5, 2021, 6:53pm UTC](https://forum.inductiveautomation.com/t/is-there-an-upper-limit-to-the-tags-that-can-be-read-with-system-opc-readvalue/52790/6 "2021-11-05T18:53:11Z")

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Hmm. Not seeing the same behavior. Have you opened it outside Excel to make sure it’s not a problem there? What version of Ignition are you using?

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<div class="post-metadata">

**Author:** ![bmeyers](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bmeyers/32/37453_2.png) [@bmeyers](https://forum.inductiveautomation.com/u/bmeyers)\
**Post date:** [November 5, 2021, 6:59pm UTC](https://forum.inductiveautomation.com/t/is-there-an-upper-limit-to-the-tags-that-can-be-read-with-system-opc-readvalue/52790/7 "2021-11-05T18:59:57Z")

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It was a typo on my part. My strings i was creating in a for loop all had a 0 in them. So instead of looking at PLC values 0-10,000 I was looking at values 10-100,000…

So a case of user error 🙂