I can click "Synchronize the clock with computer's time" and it occurs, but within a day or so, the time goes back to about 3 minutes ahead of my computer's time.

 

Why does this occur? any solution for this?

Do you have the ISY setup to synchronize with an NTP server? If so, your PC's clock is probably off and your ISY goes out of sync with it when it syncs with your NTP server.

Here is how it is set up:

 

Hmm, I'm not sure then. Any reason why you don't simply sync daily with an NTP server?

yes, the reason is very simple. I don't know what an NTP server is and don't know what time it would set my ISY to.

NTP servers are time clock servers that are available for PCs, servers, and other devices for syncing to ensure extremely accurate time.

 

Check that box and force a sync and I think you'll find that the time is very accurate. Your PC might already be syncing with an NTP server.

yes, the reason is very simple. I don't know what an NTP server is and don't know what time it would set my ISY to.

 

NTP: http://www.ntp.org/

 

The ISY will parse the time zone you have entered in the ISY to coordinate the results.

 

To find the exact coordinates of your home try http://terraserver-usa.com/default.aspx

 

When the ISY combines your Lat/Long with NTP sunrise and sunset will be accurate within one second.

 

Rand

allright! I've got my ISY set to the second and the sunset/sunrise to the second for my house.

 

Great stuff, guys! thanks.