In my last review I talked about the smart WiFi switch automatic … But I did not test it for protective properties. And after my review, heated discussions arose like the fact that this is not a machine gun, they say it cannot be set, a guard, everything will burn out, horror and sadness. But it is at the same time that this and similar devices (it is not yet clear an automatic machine with protection, or just a WiFi load switch up to 63 A) has been working for more than several years without any problems at all, performing its role in home automation. I myself am always only for safety, and I am ready to sacrifice this device for the sake of this. Let’s check and disassemble our smart device.
And so what is an automatic machine – or rather an automatic switch – it is a switching contact device that is needed to turn off and turn on (switching) electrical circuits. And it serves just to protect the wiring and consumers (our electrical appliances) from short-circuit and overload currents.
Accordingly, if you take an automatic machine of a small rating, say for 10 Amperes and connect a load of more than 2.2 kW to it, then the protection will work and the machine will turn off. The same will happen with a short circuit and even strong heating of the device. Here is a conventional 32 amp machine. Simple and probably reliable, although judging by the cost, I’m not sure about that =).
We are trying to connect it to our circuit. And the circuit will be a simple phase into the machine, from the machine to the outlet and the light bulb, and zero to the block. We turned on the machine, the light turned on and the voltage appeared in our outlet.
Now let’s make a small short circuit, for this I have a special plug with a jumper. As you can see, the machine has worked, the voltage has disappeared, there is no threat of fire
The insides of the machine
If we disassemble the machine, we will see its main protective parts.
1 – Moving and fixed contact closes our circuit.
2 – The mechanism of the electromagnetic release with a coil and a core, trips in the event of a short circuit. The short-circuit current grows very quickly, the magnetic flux builds up in the magnetic coil and the core hits the release mechanism, turning off the circuit breaker.
3 – A bimetallic plate of a thermal release, which heats up and, if the current is higher than the rating of our machine, the plate bends, presses on the release mechanism and cuts off the power supply.
4 – do not forget about the arc chute, which protects all the contacts of our machine from the corrosive action of gases that arise at the moment of burning of this very electric arc. It should be understood that the more powerful the rating and the connected power of the machine, the stronger this arc will be.
Checking the Chinese switch
Let’s try to do the same with our smart device. To do this, I will connect it after a normal, proven 10 Ampere machine
Checking. As you can see, the electricity was gone, but it was gone only because the machine put after the WiFi switch was knocked out. And this means that you should not install this device without a machine, in the event of a short circuit, it will not turn off, as it should, which can lead to a fire or failure of other household appliances.
We will check the WiFi machine after that for operability. As you can see, it turned on without any problems and continues to work.
The insides of the switch
Let me disassemble the WiFi switch, for this we drill rivets to get to the insides of our switch.
In general, there is nothing complicated about this switch. The main place is allocated to the control board, which makes this switch a smart device of our smart home. Next, there is an electromagnetic coil with a core, which turns on or off our device.
A voltage appeared on the coil, the contacts closed, if it disappeared, they opened. If you have a version of the switch with electricity metering, then the coil of the measuring module will be put on the wire going to the contact.
As you can see, no means of protection, like an automatic machine, are provided, neither from heating, nor from a short circuit, therefore we delete the word AUTOMATIC from this device, this is a smart switch on a DIN rail that is capable of operating large loads, namely with a current of up to 63 Amperes …
Thank you for your comments, I always try to make objective reviews of any product. In this case, I was confused by the Chinese name and the external similarity of this switch with a real machine. But thanks to you and my tests, we are restoring justice. This switch cannot be called an automatic device, it does not perform a protective function. But as a switching (on / off) according to a schedule, timer or any of the smart home scenarios, it is quite a suitable thing, when buying, pay attention to what is with energy monitoring, and there is without it. Better to overpay a couple of dollars and watch your electricity consumption. It is also useful for monitoring work. Thanks again to everyone for the comments.