01-08-2017 08:14 PM - edited 01-09-2017 04:14 AM
I travel a lot. And like you I like to play with my devices when I’m away. Among other things I have a Wemo switch letting my chickens out in the morning and locking them in at night, and a camera in the coop so I can make sure all is well when I’m gone.
My Internet service is good but it’s not unheard of to lose connectivity and have to reset the cable modem to get back online. That happened recently when I was out of town, and while I knew my Wemo switch was working fine (it holds the schedule within the switch), it irritated me not to be able to access the camera or other devices at my house.
So here’s what I did: I have lots of Wemo stuff, but I also use a 1st gen. SmartThings hub to interface Z-Wave devices. As mentioned before, one of Wemo’s great qualities is that the switch holds its schedules internally so they will work with or without internet connectivity. Using the SmartThings 1st gen hub, the schedules for those devices are held in the cloud so without internet they won’t fire. Inside a plastic enclosure I connected a Wemo switch and a Z-Wave switch to the same power source, then spliced the outputs of both switches to one receptacle mounted on the outside of the box. My cable modem is plugged into this receptacle. I scheduled the Z-Wave switch to be off all day, then turn on from 3:55 – 4:00 am, and 3:55 – 4:00 pm. The Wemo switch is on all day, and switches off from 3:56 – 3:59 am, and same times pm. When the internet connection is up and working, the Z-Wave switch provides power while the Wemo switch is off and there is no interruption. If there is no internet, the Wemo switch kills power to the modem and brings it back on a few minutes later, effectively resetting it. I have tested this by disconnecting the cable at its source, and it works like a charm.
01-09-2017 06:43 AM
01-09-2017 12:46 PM
Maybe someone can elaborate on this but my assumption has always been that although the Wemo's time sync has been interrupted, it keeps the last good update. I've never measured the error over the long term but it seems sunrise and sunset would be off by at least a minute every day, plus or minus.