Hello, if you are experiencing issues with Kepware or Linkmaster not returning accurate values (Unknown Quality) for certain tags from the OPC DA Client, you are not alone. Some values may be displaying as bad quality or bad vartype, with only certain values not being read. Despite being from the same OPC, other tags may be functioning correctly. As this is a local OPC, DCOMs are not the root of the issue. Do you have any suggestions on how to resolve this? These tags are being read properly in Quick Client.
Johnveloc inquired if anyone has experienced issues with Kepware or Linkmaster not returning accurate values (Unknown Quality) for certain tags from an OPC DA Client. Some values are displaying as bad quality or bad vartype, with only some values not being read. However, other tags from the same OPC are functioning correctly. As it is a local OPC, DCOM is not the cause of the problem. Any suggestions on resolving this issue? The tags are reading fine in Quick Client. What specific values are you attempting to read, and what protocol are you using (e.g., modbus tcp)? Typically, if the values can be read in the quick client but not from the other device, there may be a setup issue with the other device.
Which kepware software version is better: Enterprise V5 or EX V6?
Thank you for responding about the latest version of KepwareEX 6.xx. We are working on connecting SQL data from SCADA software using OPC DA. While we attempted OPC UA, it did not integrate properly with Kepware. The OPC Quick Client is able to retrieve data with a Native Type, likely LLong. I will confirm the protocol specifics later, but the data originates from a Windfarm, suggesting it may use industry-specific protocols similar to those utilized by Vestas.
Thank you for your response regarding the latest version of KepwareEX 6.xx. We are attempting to connect SQL data from SCADA software through OPC DA. While we tried using OPC UA, we encountered compatibility issues with Kepware. The OPC Quick Client was able to successfully read data with the Native Type, possibly LLong. I will confirm the protocol specifics later, but the data source is from a Windfarm, likely utilizing industry-specific protocols similar to those used by Vestas.
In the past, I encountered a similar issue and, although I don't recall the exact solution, it appears that the problem may have been related to using a Double instead of an LLong datatype. If I do recall the solution, I will certainly share it with you. I have found that Enterprise software tends to be more reliable than EX, particularly when utilized with panelviews.
Hey there, it sounds like you've been doing some pretty thorough diagnosing already. One possible solution could be to check if the tags that are causing issues have been configured correctly in their respective devices. Sometimes these issues stem from an incorrect data type specification or an addressing typo. I'd also suggest ensuring that these problematic tags aren't supposed to have a non-standard read rate, as that could cause inconsistent values or bad vartype displayed by Kepware or Linkmaster. Finally, you might want to consult the documentation of your OPC DA Server and see if there are any special configuration settings or limitations specific to that server. Hope this helps!
Hi! The issue you've described sounds very similar to something I've encountered in the past. It appeared to be a configuration problem in Kepware or Linkmaster. One possible solution could be to verify the tag settings in both Kepware and Linkmaster. Check for discrepancies like the Update Rate setting, since it may not be matching with your PLC, or the Deadband setting, which if not configured properly could lead to 'bad' values. Also, confirm whether the values of the troublesome tags are dependent on other tags, that, if haven't updated, might affect their readings. I hope this helps!
It sounds like a frustrating issue! Since the tags are working fine in Quick Client, I would suggest double-checking the configurations in Kepware and Linkmaster for those specific tags. Sometimes, it might be due to security settings or how the tags are defined in the project. Also, make sure that the OPC DA Client is updated to the latest version, as compatibility and bug fixes can often resolve these kinds of problems. If those don't work, reviewing the error logs for any specific messages related to the problematic tags might give some clues.
I’ve faced similar issues with Kepware where certain tags show up as "Unknown Quality" while others read fine. It could be worth checking the tag configurations and making sure there are no specific settings or issues related to those tags in the OPC server. Sometimes, even minor mismatches in the configuration or data types can cause these glitches. Additionally, reviewing the logs for any error messages at the time can help pinpoint the problem. If Quick Client is reading them without issues, it’s likely something specific in your OPC configuration or client settings. Have you tried re-subscribing to the tags or restarting the OPC server? That can sometimes clear up the glitch.
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Answer: 1. Why are some values in Kepware or Linkmaster showing as bad quality or bad vartype in the OPC DA Client? - Some values displaying as bad quality or bad vartype in Kepware or Linkmaster could be due to issues with certain tags not being read accurately.
Answer: - If only certain tags are not functioning correctly in Kepware or Linkmaster, it may be helpful to troubleshoot by checking the settings and configurations specific to those tags.
Answer: - The discrepancy in tag readings between Quick Client and Kepware or Linkmaster could indicate a possible issue within the configuration or communication settings of the OPC DA Client software.
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