
Sonoff S31
I’ve actually blogged about this before but I bought some more of these and just think that the Sonoff S31 is the best power monitoring device going. I got mine on Amazon for about $18 each and I think you can find them a buck or two cheaper in other places. Just make sure that you don’t purchase the Sonoff S31 LITE.. The Lite version DOES NOT power monitor.
The devices work with an app called EWELink but the company that makes all this is called iTead and they are a Chinese company based in China and some people have caught their app sending back interesting information to the home server in China. In short……..I don’t trust the app. You can use them right out of the box with the app but that’s not what I’m all about here at John’s Tech Blog.
So what I do is to modify the devices firmware with something called Tasmota which works on Wifi, creates a web page that displays all your vital information and it ONLY reports to any server if you TELL IT TO. Mine reports to MY machine to machine protocol server (MQTT) so I can tie the switches into my Home Automation software so I can turn them on and off. Also you can do really cool stuff which I won’t go into here in great detail. For example, I can have it send me an email if it sees a refrigerator showing so many watts for so long a period of time. Excessive wattage would be from the light bulb being on so maybe me pulling 60 extra watts for 2 minutes means someone left the door ajar. Cool.








