Since this switch doesn't have a battery back-up, it's not the most reliable solution for this purpose.

The ZEN15 Power Switch won't have time to send any information to your hub if power goes out, but it will show as "unavailable", "offline", or a variation of this depending on your hub. Without a battery back-up, there's no way for it to send a signal without power. 

Currently, the best solution for monitoring power outages is with this kit, consisting of a door/window sensor with dry contact terminals built-in, our NO/NC accessory relay, and a 12V power supply. The sensor runs on a battery and will send an "open" report to the hub when power is lost at the relay and power supply. Once the power supply is plugged in and getting power, the sensor will simply report as closed. If the power is cut to the supply, you can schedule a text or email through your Z-Wave interface notifying you about the event.  In addition to these components, you would need to make sure your hub has a back-up power source so that is can send and receive messages when the power goes down.

If you have any questions about power outage status functionality, let us know!