In stores, you can often find switches in which the backlight is already integrated. However, it is unlikely that anyone will want to just change the installed switch. But looking for a touch key in the dark is also not always convenient.
Practicality of illuminated switches
The backlit switch, the connection diagram of which is almost the same as that of conventional switches, has become very popular. Anyone who is tired of looking for a switch in the night dark can make small changes to this device, even if he does not have special knowledge in electrics.
An LED can be inserted into any switch using fairly simple schemes. Between themselves, affordable schemes differ in their characteristics, and not just in the complete set. For example, the switch may not want to work due to the LED lamp installed in the luminaire. If the lamps are energy-saving, then they can glow in the dark or flicker, which is also not the correct result.
Switch Connection Diagrams
There are many acceptable schemes, each of which has its pros and cons. It is not difficult to understand the existing schemes for connecting LED backlight to the switch.
For example, a backlit switch, the connection diagram of which is presented below.
When the switch is in the "Off" position, the current passes through the resistance (R1 is any, in the range from 100 to 150 kOhm). After resistance, it passes through VD2 (an LED that lights up). In order to protect the LED from voltage, we put the diode VD1. The resistor with a current of 3 mA shines especially well with such a connection scheme. If it turns out that the LED is dimly lit, then the resistance rating should be reduced. The LED and diode in this circuit will suit any. You can calculate the necessary parameters of the resistor yourself. It is enough to recall the classical law of current strength.
Consider another backlit switch, the connection diagram of which is extremely simple, but with a slight drawback. The fact is that it consumes about 1 kilowatt per month.
The ends directed downwards are connected to the terminals. If there is no soldering iron in the house, or for some reason there is no desire to tinker with this, then this circuit fits perfectly. It is made on twists. Although, for reasons of safety and durability of the device, it is better to solder the connection points, and insulate the resistor well.
Circuit breaker LED illumination
To increase the glow level by an order of magnitude, you can use a capacitor. A resistor current, on the contrary, reduce to 90-100 ohms. You can use a backlit switch, the connection diagram of which differs from the previous one in that a capacitor is used instead of a resistor. A resistor (R1) plays the role of a limiter of the charging current.
True, the backlight assembled according to this scheme is large in size, but it is characterized by extremely low power consumption - about 0.05 watts per month.
Connecting the passage switch
If we consider the backlit Legrand switch, the connection diagram of which is higher, it should be noted that it is characterized by the safety of the use of this product, which is made of materials that significantly increase the service life. And the simplicity of connecting the circuit breakers of this company is out of the question, so everything is thought out and easy to implement.
In the manufacture of circuit breakers, polycarbonate and galvanized steel are used. Screws, clamps and a support - all this is made of this metal. The keys, mechanisms, case and frame are made of polycarbonate. And this is a guarantee that for a long time the Legrand switch with a backlight, the connection diagram of which is extremely simple, will not crack or collapse from solar radiation.
Installation of a two-gang switch
Legrand two-gang walk-through switches are distinguished by the presence of a pair of contacts independent of each other. When pressing the keys, they switch the upper lines to the lower ones, and at the same time the upper contacts are made with no final output. And the lower contacts are connected to the second, same pass-through switch.
Knowing how the left and right group of contacts are arranged, it is easy to understand how to connect a passage switch.
Connecting a pair of passage switches is extremely simple. The phase that leaves the electrical panel of the apartment or house is fed to the contact of the second switch, while within the framework of the entire group the contacts are connected by a jumper. And those contacts that are in the left group supply current to lighting devices that are independent of each other. It is important to consider one rule here. In no case should these two contacts be interconnected. Then all the four cross contacts must be linked together as a pair.
Legrand circuit breakers
Legrand is perhaps the most widespread brand among electrical appliances, and therefore most prefer to use their products, or close to them, but also well-known companies.
Among the products related to electrical fittings, it is necessary to distinguish sockets suitable for television and telephone networks - low-current, and all of them, except for excellent design, are of high quality, from which they gained wide popularity not only in our country, but throughout the world.
Operational principle of passage switches
Externally, a conventional switch practically does not differ from a passage switch and it is impossible to visually distinguish them without revealing the design. The difference lies in the internal structure. A conventional switch opens or closes a circuit that carries an electric current, and a loop-through, connecting one line, disconnects the other. That is, in other words, during the operation of the passage switch, no matter which pair of keys is pressed, the switch is ready for operation. Pressed the left on one switch - the light went out. They pressed the second one on it, or the key on the second switch - the light is on again. This is undoubtedly very convenient.
In other words, with a conventional single-key switch, both contacts are working, and at the walk-through, as many as three. Because the second contact, which acts as an output, is connected to a second switch, paired. And when connecting two-gang walk-through switches, the number of contacts increases already to six.
If you carefully consider the connection diagram below, you can easily cope with the installation of any loop-through switches and install all the necessary devices so that the circuit functions normally. The main thing is to observe safety precautions, do not work with the mains voltage turned on, and make sure that a workable circuit is used.
Illuminated through-switch connections
Consider, perhaps, the most undemanding circuit with which you can connect such switches. Zero in the circuit is indicated in blue. He, once in the junction box, then goes to the lighting lamp. The orange wire is the phase. It passes from the same box to the input of the first of the switches. Then, the black wires at the outputs must be connected to the input terminals of the second switch. And then, with just one wire, go to the lamp.
A double switch with a backlight, the connection diagram of which is identical to those considered, is used as a device for controlling light sources that are spaced from each other and can be located at a considerable distance. But you need to manage them from a specific place, and sometimes from two or three.
The comfort effect is especially noticeable when a two-key switch with a backlight is used, the connection diagram of which is included in the kit, on stairs, in large rooms, when you do not want to get up, for example, from the bed to turn off the light in the bedroom. If the switch is located at the door - it is inconvenient before bedtime. Therefore, it is more logical to use a passage switch. One is installed as usual, at the door of the room, and the second near the bed so that you can turn off the light without getting up.
Often use automatic adjustment off and on the light. To do this , detectors that respond to movement or sound are connected to the bulbs . Or for lighting - when it becomes dark, the light will turn on on its own and vice versa.
Thus, if a single-key switch with a backlight is used, the connection diagram of which has already been considered, as well as through switches with a different number of keys, any results in the implementation of design ideas and projects are easily achieved. And the simplicity of installation makes it possible to independently carry out work without resorting to the services of expensive specialists.