Different UTC time than the client

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Hello, community!

I’m currently working with OnlineChartHDA, but I’m having an issue with the UTC settings. I live in South Korea and have configured Time Synchronization using the NTP time settings. It was working fine until yesterday, but starting today, I’m getting an error like the one in the first screenshot.

After exchanging data with another PLC via TCP communication, that error message started appearing.

What could be the problem?

Thank you!

2

Hi,

I can’t swear, but it looks like that one of the systems uses UTC time, while the other one uses local time for the datapoint timestamps (I assume you’re using OPC UA for the communication to the other PLC?).

3

Just leaving this here for any Korean users who might see it.

If you use a Korean NTP server address, the server and client times may become desynchronized after a few days. Manually updating the time settings fixes the issue and allows it to work again. I’m not sure about a permanent solution, but at least I’ve found a temporary fix.

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4

Hello Hansol,

A couple of points on what you’ve provided here:

  • You have your time zone set to GMT/London. If the machine is located in that time zone, you might consider a more local NTP server. Also, your comment about a Korean NTP server makes less sense.
  • It looks like you have spaces in your NTP Server names. There should never be a space in a URL. For Korea, your closest NTP servers from ntppool.org are:
    0.kr.pool.ntp.org
    1.asia.pool.ntp.org
    0.asia.pool.ntp.org
  • Make sure the PLC can reach these NTP servers with correct DNS and Default Gateway. You should see time synchronization notices in the logger, or you can implement the AsIcmp library to try to ping the NTP servers.

-Austin

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