On our SC models, the time and date are synced from the server/computer where the synchronization engine is installed.
The synchronization of time is set to update once every 24/h.
Also, if the cabinet is out of power there is a small battery on the PCB where the only function is to save the date and time.
So, make sure you have the correct date and time on the server/computer, and if you experience that you "loose" time and date settings often, exchange the battery on the PCB.