Building An ESP32 Smart Power Strip From Scratch

June 10, 2020 by Tom Nardi 33 Comments

Surely the most straightforward way of creating a smart power strip would be to take an existing model and hack in some relays that you could fire with a WiFi-enabled microcontroller. But where’s the fun in that? Instead of repurposing a commercial power strip for his recent project, [Md Raz] decided to just build the whole thing himself.

The project started with a 3D printed enclosure that could hold the electronics and three panel mount sockets. The use of heat-set inserts makes it a bit more robust for future upgrade work, but otherwise it’s a fairly simple rectangular design. Nobody ever said a power strip had to be pretty, right? In addition to the panel mount sockets, there’s also a AC-DC converter to step mains voltage down to 5 VDC for the ESP32.

In addition to the microcontroller, the custom PCB in the power strip holds a trio of MOSFETs connected to AQH2223 solid state relay (SSR) chips. Once the ESP32 toggles the line attached to each MOSFET, the indicator LED above the outlet goes on and the appropriate SSR is thrown to turn on the power. With a simple web interface running on the microcontroller, all three outlets can be independently controlled from any device with a web browser.

If you’d like to limit your interaction with mains voltages, then we’ve seen some projects that commandeer the low-voltage side of a commercial smart power strip. But remember, putting a Raspberry Pi inside of a power strip might seem suspicious to some folks.

Smart Plugs Don’t Save You Energy, But Don’t Consume Much Either

May 29, 2018 by Bob Baddeley 60 Comments

Amazon Alexa, Google Home, and just about every electronic device manufacturer are jumping on the bandwagon of connected devices. They promise us the ability to turn on our toaster from another room, unlock our doors just by shouting at them from outside, and change the channel on our TV through perfectly enunciating a sentence instead of mashing the buttons on our remotes like chumps. And yet, despite all this new-fangled finger-less control, there is an unanswered question: does this technology save us energy in the long run?

For years we’ve been hearing about vampire power and all the devices in our home that sit in standby, waiting for their masters to turn them on, quietly burning power to listen for that signal to wake. Fortunately the One Watt Initiative and general awareness and design for energy savings has cut out a lot of this phantom load. So how does the smart home, which essentially adds a bunch of connected vampires to our base load, end up saving money in the long run? And is it better than other alternatives or just good habits? I put these questions to the test with today’s smart power strips and controllable outlets.

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IoT Power Strip Lets You Control All Your Holiday Lights

December 27, 2015 by James Hobson 10 Comments

As IoT devices become more prevalent in the consumer world, how long will it be before it’s cheaper to buy one, than to make one? Definitely not yet, which means if you want your very own IoT power strip — you’ll have to make your own. Good thing it’s not that hard!

[Dev-Lab] came up with this project which allows him to control several outlets with his phone. What we really like about it is that he designed a 3D printed housing that fits on the end of the power-strip. This keeps all messy wires out of sight, and it looks like it was designed to be there!

The beauty with an IoT device like this is that it doesn’t require any infrastructure besides a WiFi enabled device with an HTTP browser — the ESP8266 module means no server is necessary. An Arduino was used in the project just because it was quick an easy to do. But it really boils down to being a glorified pin expander. This could very easily be fixed by upgrading from an ESP01 to and ESP03 module to get more IO broken out on the carrier board. If you do this, let us know!

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Go On A Power Trip With Powerduino

May 3, 2014 by Kristina Panos 10 Comments

powerduino Things don’t always run the way we want them to or operate at the ideal temperature out of the box. Instead of spending extra for power controls that may or may not meet your needs, wouldn’t it make more sense to dial in the ideal level from the source? That’s what [dekuNukem] had in mind when he decided to make Powerduino, an arduino-compatible programmable power strip.

With Powerduino, [dekuNukem] can control the electrical consumption of all kinds of things without ever worrying about the irreversible deadliness of mains voltage. It actually uses a Teensy 3.1 which can be programmed with the Arduino IDE through the micro USB connector. He’s really tricked it out to the point of putting Kill A Watt meters to shame. A wi-fi module lets him control any of the outlets from anywhere, and the RTC module lets him make customized schedules for them. Powerduino has an SD card slot for logging energy consumption, and a 20 x 4 LCD screen makes it easy to directly interface with the power strip.

The Powerduino code is up on GitHub, and [dekuNukem]’s walkthrough video is after the jump.

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Build Your Own Dumb USB Power Strip

February 22, 2013 by Mike Szczys 21 Comments

diy-usb-power-strip

Here’s a USB charging center which [Kenneth Finnegan] built using parts from his junk bin. We’d like to reiterate our claim that he must have the most magical of junk bins (the last thing we saw him pull out of it was a 24-port managed Ethernet switch).

The jack on the side accepts the barrel connector from a 12V wall wart. [Kenneth] mentions that the 2.1mm jack is a standard he uses in all of his projects. Inside there’s a switch mode power supply that provides the regulated 5V to each USB port. We really like the fact that he added some protection; diy is no fun if you end up frying your beloved multi-hundred dollar devices. The yellow components are polyfuses which will cut the power if 600 mA of current is exceeded. This works great for almost all of his devices, but his iPod 4G doesn’t like the system. It sees the voltage dip just a bit and stops charging entirely.

Malicious Raspberry Pi Power Strip Looks A Bit Scary

October 4, 2012 by Mike Szczys 28 Comments

What you see here is a Raspberry Pi shoehorned into a power strip. The idea is to leverage the power and low-cost of this board into a stealthy network observation device. It packs a similar punch as the Power Pwn but should cost at least $1100 less!

The fact that when you plug your Ethernet into this ‘surge protector’ it starts sniffing your traffic doesn’t really scare us. It’s the mains wiring that traverses the RPi itself that’s a bit unnerving. Call us overly-protective, but we like to see some shielding between our high-voltage and low-voltage components. But that aside, the rest of the hack is pretty solid. That item wrapped in electrical tape is a power converter for the board itself. It’s not shown here, but the NIC is patched into the surge protector’s RJ-45 connector. The one thing that might be nice to include is a WiFi nub so that you can access the strip wirelessly. This would open the door for other snooping items, like a small microphone.

Bluetooth Control In A Power Strip

August 28, 2012 by Mike Szczys 16 Comments

[Mansour] had a ceramic space heater mounted near the ceiling of his room. Since heat rises this is not the best design. He upgraded to an infrared heater which works a lot better, but lacks the timer function he used on the old unit. His solution wasn’t just to add a timer. He ended up building a Bluetooth module into a power strip in order to control the device wirelessly. He ends up losing all but two outlets on the strip, but everything fits inside the original case so we think it’s a reasonable trade-off.

He uses relays on both the live and neutral wires to switch the two outlets. These are driven via MOSFETs to protect the ATmega168 which controls the board. The microcontroller and Bluetooth module both need a regulated DC power source, so he included a transformer and regulator in the mix. After the break you can see him demonstrating the system using two lamps. There’s even a terminal interface which lets you select different control commands by sending the appropriate character. This interface makes script a breeze.

At least this power strip doesn’t spy on you.

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