DI-2108 Stand-alone Mode RTC accuracy and drift

DI-2108 Stand-alone Mode RTC accuracy and drift

I'm planning to use a DI-2108 or DI-2108-P in stand-alone mode, set up to "Record on Power Startup" via the WinDaq Dashboard.

I'm a long time DI-148U user so I'm familiar with recording in real-time using WinDaq & having the PC's time synchronized to the data acquisition & logging function.

How does this work in stand-alone mode to synchronize time?  I have to assume there is a RTC (real time clock) on board the DI-2108?  What are the specs for time accuracy and drift over time?  I don't see that in the datasheet.