How Do Smart Plugs Work? | Behind Scene

Well, I think most of you know what a smart plug is? Am I right? If not, please hope over to below section for a small introduction about smart plugs.

However, this article is not about the usage of smart plugs. It’s about how smart plugs work. This will be a little bit technical. Anyway, I will try my best to keep everything understandable language, yet not destroying the core details.

What is a smart plug?

Smart plug is a device which can plug into your old regular wall power outlet. The smart plug has its own outer interface to plug any electrical instrument that could go into your old power outlet.

So, now you could think about that, what is so special about this. The special point in smart plug is we can control it remotely. The controlling process can be done via the internet or using your home WIFI network. Oh, you can do that by using your mobile phone too.

Since we can remotely control the power outlet, we can manage anything that connected into it. That means we do not need to physically go near to the power outlet. We can turn on or off it by just pressing our mobile phone buttons or else using voice (through Alexa or any other smart home controller)

Not only that feature, but smart plugs also have auto schedules, power monitoring, and advance safety options.

Best things to use smart plugs for

Just, for example, I’ll list out several ways that we can use a smart plug in our house. Actually, there are many ways. These are some primary uses.

Television or Radio – Turning ON or OFF your TV or radio is now comfortable with smart plug.

Home Lights – How about your home lights turn on automatically at night and turn off in mornings. Further, adding some custom schedule or random turn ON/OFF cycles to indicate you are at home when you are really not at home.

Battery chargers – When you do not have an automatic shutdown feature in your battery charger, then smart plug can save you. It does have the capability to turn off or on your charger whenever you told or scheduled.

Washing machines – You can use a smart plug to monitor or get a notification when your washing cycles were finished. This can actually save some energy usage. Especially in old washing machines.

Coffee Makes – How about getting a coffee just after you wake up in the morning. All you need to do is, set instructions to your smart plug for turn on your coffee maker at your wake up time.

Sprinklers in GardenSometimes, with busy time schedules, you can forget or do not able to water your precise garden. Well, using a smart plug, you can automate your sprinklers to do your deed.

If you are interested in checking more usages, in a detailed way, I have this excellent article for you. It will explain 12 best ways to use smart plugs in your home.

The operating mechanism of a smart plug

To explain how smart plugs works, I have designed a basic diagram as shown below. Please consider that this is a basic diagram. Actual systems may contain more specific circuits for special functions.

Also, the structure can change dramatically based on the manufacturer’s design.

smart plug internal structure

Anyway, this diagram is enough to understand the main working principle behind the smart plug.

So, like I have drawn in this diagram, most of the smart plugs have safety features in their power input and output lines. Basically, there are fuses that will burn out at larger current values.

Also, there will be a central controller board. This is the circuit that will control all of your biddings. Most probably, a microcontroller with custom firmware will handle these operations. If you are wondering what a microcontroller and firmware are, then I can explain it using a small example.

The microcontroller is a small IC which is similar to your laptop or PC, but very small and limited capabilities. Then the firmware is kind of your operating system (Windows 10 or apple OS..etc) that make your PC useful to do your daily tasks.

The microcontroller will connect to a display panel or LED to indicate the current status of the smart plug. Also, it will have the control of an antenna which will get your commands through Wi-Fi, Bluetooth or ZigBee. Based on your received commands, the microcontroller will turn on or off the power output line through an electrical relay.  

Moreover, there is a small memory chip inside the main controller board to keep your schedules. The microcontroller is programmed by the manufactures to automatically check these memory chips to execute your scheduled commands.

All these things mean that your smart plug is like a tiny computer which is specially designed to do a few specific tasks continuously.

How do smart plugs work with Alexa, Google Home..etc

Alright, let’s check how these smart plugs work with smart home controllers such as Alexa or Google Home.  (want to know how smart bulbs works too, then click here)

When you installed a smart home controller such as Alexa, it will connect to your home Wi-Fi network, or it will generate an internal Wi-Fi network. Then, your smart plugs will connect to this network through its internal Wi-Fi antenna.

Once, you have successfully connected smart plug into your smart home controller, both devices will share a direct link to communicated to each other (through Wi-Fi).

If you want to know how to connect a smart plug into Alexa, check this step by step guide that I have written in one of my previous article.

The Alexa, or else another type of smart home controller, do have an ability to capture your voice commands. These controllers will understand your command and it will send a unique Wi-Fi signal into your smart plug to execute your individual instruction.

If you are interested in checking some of the best smart plugs, then check this article. In that article, I have reviewed the best smart plugs that will work with Alexa. Actually, there are good to go with other smart home controllers too. Such as google home.

Recent Posts