Compactlogix PLC tags not showing tags values in Kepware

[MR_9624773]

I'm trying to communicate CompactLogix L-18 ERM QBFC1 (firmware version 20) with Kepware (V6.13) and facing one strange issue.

If I add the tags manually, I'm getting bad quality data in Kepware. If I try to add tags using automatic tag generation, I'm able to get few tags with good quality data but not all the tags present in the controller. Using .L5K file option, I'm able to add automatically all the tags present in the controller but data quality for all the tags is showing bad.

Please help.

[ntripathi · Accepted solution]

Greeting @MR_9624773,

I hope you're doing well.

Thanks for the detailed description. Based on your issue and the latest findings, here are some possible causes and solutions for the bad quality data you're seeing in Kepware when connecting to your CompactLogix L-18ERM QBFC1 (firmware v20):

Causes:

• Kepware can only access controller-scoped (global) tags. If you're trying to access program-scoped (local) tags, they won't be visible or will show bad quality

• Some complex or user-defined data types (UDTs) may not be fully supported or may require specific configuration in Kepware.
• Kepware V6.13 should support CompactLogix v20, but there may be subtle compatibility issues.
• If the .L5K file is outdated or mismatched with the actual controller, tags may import but not link correctly.
• Automatic browsing may not retrieve all tags due to size limits or communication timeouts.

• The controller might have access restrictions or security settings that block external reads.

Fixes:

• Ensure the tags you want to access are controller-scoped.
• Try testing with simple data types (e.g., INT, REAL, BOOL) to verify communication.
• Ensure you're using the Logix5000 driver in Kepware and that it's configured for Firmware v20.
• Export a fresh .L5K file from Studio 5000 and re-import it into Kepware
• Try increasing the Browse Timeout and Max Items per Request in the Kepware channel settings.
• Check the controller’s communication settings and ensure external access is enabled.

If you have any questions or need further assistance, please feel free to contact us. We're happy to help.