Laptop Charger Auto Switch

Pandemic arrived and you just started working from home, using your company laptop, or just figured it out a full desktop PC is an overkill for you, and you decided to move to a simpler and more versatile laptop.
All this two options have one thing in common: a laptop being used by hours, plugged into the wall, that you daily have to connect and disconnect from wall socket (if you don't do this, you should start!).

But what if the charger connects itself to main voltage when needed and unplug when you finish all your work? That's why I'm here. I had this "issue" of plugging and unplugging it daily, and realized that was an easy way to automatize this process, with wasting too much money. Using power from an USB port, we will automatically turn on and off the laptop charger. Simple as that.

WARNING: this project uses AC mains voltage. Do not attempt making this project if you are not used with electricity, and never touch anything while it is plugged to wall socket. AC voltage is lethal and must be handled with caution. I am not responsible for any injury or damage, material losses or other consequences of your attempt to follow this instructables.

1 or 2 surface mounted outlets (you'll understand later why)
1 male power plug (a power cord will be made with it)
1 meter of 1 mm² parallel wires (at least 450V rated)
1 Solid state relay module OR 5V relay module (we will be using modules, once this make things easier and quicker)
1 USB cable
screws, double-sided tape and usual tools.

So, we will be switching an AC load using DC power, we will need a power switch. For this task, the best option is a SSR with zero-crossing switching feature (first picture), but SSRs without it will work as well as. But make sure your charger doesn't draws more than 1.5 A (read its label). Although most of SSR modules are 2 A rated, we must take into account the temperature derating factor.

If your charger or charger + second load draws over 1.5 A, you'd better pick a common relay module (second picture). Those are generally rated, at least, for 10 A, so you will be good. A beefier SSR won't be worthy it (at least, here in Brazil it isn't).

Choosing one or two power sockets is up to your creativity. I used two, one for my charger and another for powering an LED strip behind my laptop, so it not only indicates it's on, but also reduces eye strain and makes a cool effect.

Following the amazing artwork, it's all about putting it all together. Make sure all the connections are tightly made, no loose wires, no short circuits. Just pay attention if your relay module is activated with high or low level. If it's low level triggered, just bridge the INPUT (or TRIGGER) input and 0V input together, instead with 5V as shown in the picture. If there is enough room, you can fit it all inside the surface mounted outlet, as I did. Just cut some plastic here and then and everything fits fine and firmly.
Pay especial attention when doing so to put AC and DC cables as far and apart as possible. A short circuit here and your laptop is dead. Also, the relay MUST be switching the live wire, not the neutral. This is done for safety reasons. Don't question: just do it!

If you intend to use a second load, as I did, just connect the second outlet in parallel with the first one.
I didn't show grounding connection 'cause my charger uses a two pins plug, but if yours use three pins, ensure the grounding wire is properly set as neutral is connected.

After everything is done, test it connecting the USB to a USB charger. If your board has a LED, it should be lit. Using a multimeter, check if there is continuity between live pin from plug and the controlled outlet: you should see a low resistance, and with USB cable disconnected, an open circuit. If you have this, you successfully made it! Congrats, buddy.

Now, you only need to mount it wherever you want. I mounted mine under my desk.
Connect the USB cable to your laptop and turn it on (I suggest using an USB hub, if you don't already use it). Again, repeat the previous continuity test. If it seems OK, you are good to connect your circuit to AC power and your laptop charger to it.
If, after turning off your laptop the circuit stays on, check your BIOS for USB power settings.

If you succeed, congratulations, you are now more lazy and sedentary, but at least you did something cool to show to your friends and never worry about forgetting your charger plugged without using your laptop.

Hope you enjoy my idea and make the most of it.
Stay safe and creative.