How to automatically synchronize the time and date for several logic machines?

[richard7]

Dear Admin,

I have set the LocalClockDispersion parameter to 0 in Windows(with regedit).
Then,  I changed the clock of  PC, for example, from 16:31 to 15:31.
10 minutes later, nothing happen, the LM5 still run the clock with itself pace.
What is the frequency of NTP synchronization? every munite or every hour?

Thanks.
Richard