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

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

How does it fail?

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

#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?

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

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

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?

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 :slight_smile:

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