Issue
A Niagara G3 ENS locks up & stops communicating with all ENCs. All stations are running version 3.3.22. The "sysInfo" spy page shows the correct time, but clock ticks show an extremely large value. A station restart cures the issue for about 6-8 weeks.
Environment
Niagara G3 ENS
Cause
A known software error in version 3.3.22, which cause the engine timing to fail.
Resolution
This is a known issue with versions 3.3.24 and earlier. Tridium describes it on their website - http://www.niagara-central.com. Search for Issue #11404. It has been fixed in versions 3.3.25 and later. If it's not possible to upgrade versions, then the ENS must be restarted every 49 days (or more).