Even after power loss to hub and the house , ST app still shows it connected to the hub and tries to send commands.
Would it be nice for app to some how tell user that hub is offline ?
It does! It should pop up a dialog box that says something like “Your hub has not reported in a while. Looks like it is offline.”
If you don’t get that dialog box, you might want to get in touch with support to let them know. Could be a recent regression. Unfortunately, there is no public bug tracker.
how long does it have to be offline for the notification? It it a push notification or only if you open the app??
Unsure about how long it has to be offline, but I had to open the app for the dialog box to show.
If you are looking for a more reliable way to be notified of power outages at home, you should connect your hub, router and modem to a UPS. Plug in you SmartSense Motion. When it looses power, it will send an event with the value of powerSource changing from powered to battery. You can handle that event in a SmartApp and send a push notification, sound your battery powered siren, or trigger whatever else you’d like it to do in the event of power loss.
Pretty sure it takes 5 to 10 minutes for it to see that it is offline. You will not get a push notification. You might get a notification in the app, but not positive on that.
We’ll I did get a notification in the app but it would be wayyyy more useful to get a push notification.
Sometimes I sleep. What if I don’t want these messages to wake me up at night? We will only send you the low-battery alerts between 9 a.m. and 9 p.m. local time. We will send you a notification about your Hub going offline as soon as it happens–as you’d want to know that your system is down in case, y’know, there’s an intruder trying to break in at midnight.
@emilyallen Well then I hope that is one reallly slow intruder 
oops wrong thread, in reference to the 30 minute window
There’s actually about a 30 minute delay before the push notification goes out. Sorry, we should have done a better job of communicating that!
@coryds Good catch, we clarified the language on that blog post.
Keep on not letting us get away with anything Cory. 
@emilyallen You know I’m just messing with you 
Keep up the good work, these are some much needed features I’ve been waiting for!