Hello.
You can enable deep sleep mode after 3 hours, If You configure sleep mode timeout to something like 180 minutes.
But device has to to have open link timeout configured as as shorter interval of seconds than a send period, as link between server and device has to be closed for device to enter sleep mode once it has no movement or Ignition detected.
About Sleep mode: https://wiki.teltonika-gps.com/view/FMB120_Sleep_modes#Deep_Sleep_mode
It is not possible to configure device stop sending records at all after certain amount of time, but You can configure On stop settings to generate and send records as often as 1 hour and when it is on the move You can configure to generate and send records as frequently as possible.
If there are more questions regarding this topic, please ask.
Best Regards
