The other day, a friend of mine posted his “latest gadget” – It was a box containing a basic mechanical timer and a hacked ON/OFF remote. The idea was to have some control over the basic EVSE (electric car charging station) for his car. Mostly, he wanted it to turn off automatically after a certain amount of time, but he also wanted manual ON/OFF control. He built all the parts into a project box and it looked and worked GREAT!
That got me thinking…
I already have a Samsung Smart Things home automation system. (https://amzn.to/2LiYjKy)
So far, I’ve really only used it for a few basic things such as automating my front porch light to turn on automatically at sunset. Some of the other neat features include timers and control from a smart phone.
Hey, could I set my electric car to charge automatically at a certain time, or turn it on and off from my phone! It sure would be cool to do that with the Samsung Smart Things system.
I still had one more “smart switch” leftover from the Samsung “kit” which I had purchased. I quickly wired up the switch to a short piece of cord with a 120V plug end on it. On the other end of the switch, I wired an electric outlet box. On my smart phone, I used the Samsung app to “Add a Thing”, and quickly had remote control over the switch and thus electric outlet.
Recently, I’ve been testing out a Duosida EVSE. (https://amzn.to/2NhJEj8)
One advantage of that unit is that it runs on either 120V OR 240V. I plugged it in to the switched electric outlet, and the other end in to the car. By controlling the switch, I could turn the EVSE on and off, and the car would start charging. I tested a few different aspects of it, and it worked great!
The main downside at this point is that the switch I was using is actually a dimmer. Even though I had it set to “Full power ON, Full power OFF”, it’s not quite the right device. On top of that, the full power of the EVSE was being drawn through the switch. But as a proof of concept, it worked great!
The next step will be to get a project box and mount a 240V contactor inside of it. I’ll use a “Smart Switch” to turn the contactor on and off to make or break 240V power to my EVSE. I’m also planning on adding a small multimeter to the project box so that I can always see how much power the car is drawing. I’ll also likely add a small power indicator light as a nice visual cue as to whether power is on or not.
When I’m done, I’ll be able to plug in my car whenever I get home, but have it programmed only to turn on after a certain time (such as PAST peak power use in the evening) and still have manual control to immediately turn power on and off.
While some of those types of features are built into apps that come with certain cars, some of those apps are slow or unreliable. Besides, I already have the Smart Things system, so expanding it to control my car seems like a natural fit. Lastly, while I have NOT worked with any of the home automation assistants or smart speakers, those could be interesting to experiment with as well.
Just imagine, “Alexa, Charge my car!”
Stay tuned! Over the next week or two, I’ll be working on the 240V, properly built interface for Home Automation control of an electric car!
Until next time, stay charged up!
-Ben
