Upgrade the smart switch, how much is the difference between the "zero fire version" and "single fire" wiring methods?

I'm sure you all know that , Nowadays, the types of intelligent switches have been blooming , There are all kinds of , For example, open the rice house APP, There will be all kinds of switches .

Actually , If these switches are distinguished according to the communication protocol  , Basic is zigbee/ Bluetooth and WiFi These three , But each one has corresponding single fire version and zero fire version . Then talk to everyone “ Zero fire ”、“ Single fire ” Differences in wiring methods , Help you upgrade the smart switch , Little detours .

Compared with traditional mechanical switches, intelligent switches , The biggest difference is that the electronic circuit is used to open and close instead of the mechanical combination and disconnection .

however , The smart switch must always be live , To ensure that control instructions are received at any time . therefore , In connection mode , It is essentially different from the traditional mechanical switch , This is also the emergence of  “ Zero fire ”、“ Single fire ” The cause of the wiring mode discussion .

So here comes the question , If a mechanical switch is replaced by a smart switch , There is only live wire on the switch , There is no zero line , How to supply power ？

“ Zero fire version ” Wiring mode intelligent switch , An additional zero line is required to supply power to the power supply module of the intelligent switch , To ensure that the power supply module can supply power to the wireless module at any time , In order to receive the signal .

But the shortcomings are also very significant ： The switch base shall be reserved during installation 1 Root FireWire and 1 Zero line . This is not a big problem for newly decorated houses , But in the renovation of old houses 、 When replacing an ordinary switch with a smart switch , Will face the embarrassment of the lack of zero line , In general, such scenes , Large area re wiring is also unrealistic .

Single fire switch , seeing the name of a thing one thinks of its function , There is only one live wire on the input side , At the output side, the load control line is connected with the lamp , The neutral line is connected to the other side of the lamp . In order to form a complete power supply circuit , The current to the intelligent switch enters from the live wire , Through the load control line , After lamp load , From the zero line .

To ensure that the intelligent switch is ready to receive signals at any time , Even when the light is off , There also needs to be current flowing from the electrical load . This will cause current to flow when the lamp is turned off , For some lamps with low power , When a small current passes , Slight light or flicker may occur .

So , Because the lamps and lanterns on the market are very different , Everyone has different choices .