As of right now we do not have a function to set up notifications when a device is not communicating or has not been for an x number of hours.
In several cases, the cause for a device to not communicate is because the device was unplugged, or if the driver was in a bumpy road, and no zip tie is being used, the device can disconnect and lose power. As well as a bad installation. For these cases we do have two reports that can send a notification of when this happens.
The first is a default rule in the database called "Unauthorized Device Removal." This rule will send the notification once the device has been plugged back in after unplugging it. Meaning that the notification will be sent once the device receives power again.
The second is a report that identifies unplug events caused by device power issues or installation issues due to user error. This report is called "Device Unplug Report" and can be found in the Marketplace tab in the database.
I hope you find this helpful. Please let me know if you have any additional questions.