Hello.

I do not understand what you mean by "I checked the packet (tcp.port=135) through Wireshark and found that the request packet was not found.".
Please try to explain in more detail what you did.

Regards

Hello.

Here is what we suggest, in this order:

1. Upgrade to QuickOPC 2022.1. There have been bug fixes that can, at least in theory, cause this.
2. If upgrade to 2022.1 does not help, use read from device (see previous post).
3. If reads from device do not help, try to use OPC Analyzer (with our help) to get the trace f the communication between the OPC client and the server, and then analyze which side is at fault.

Regards

Thank you.

By default, QuickOPC uses "maximum value age" of 1 second. This can result in receiving values that are not completely up-to-date. But there can be other reasons (such as server problem) for the behavior you described.

On the QuickOPC side, you can reduce the "maximum value" to zero, by specifying a read from the device. See:

- opclabs.doc-that.com/files/onlinedocs/QuickOpc/Latest/User%2...ems%20from%20the%20device.html
- opclabs.doc-that.com/files/onlinedocs/QuickOpc/Latest/User%2...m%20OPC%20Classic%20Items.html

This is the "brute force" approach (reading from the device is discourage din OPC specifications, for performance reasons).

Also, please post here the QuickOPC version&build number you are using (there is an additional piece of advise if you are on some old versions).

Regards

Hello.

I first need some clarification. In your screenshot, you have highlighted the timestamps. But, the timestamp is just an information about when the data was collected, and it even does not have to change when the value itself has not changed. So, complaint about "old values" is not the same as "old timestamps". OPC Data Access should deliver the up-to-date values to you. But, the value does not necessarily have the timestamp close to the time of the OPC read.

So, do you have any indication that the actual *values* you are too old at the time of the reading? That is, that you should have received a different, newer value?

Regards

Note: It is true that by default, values from cache can be supplied to you. There are ways to control this. More about it after you answer this.