The light turns on with a clap. Cotton switch. Self-production of the device

Previously, we could only watch in the movies how the hero of the film enters the room, claps his hands and the lights come on. For us, such an action seemed fantastic. Nevertheless, sooner or later any fantastic inventions come to life in real life. And the cotton switch is now gaining more and more popularity. But for most of us, it still remains beyond our understanding and knowledge of electricity. We invite you to take a closer look at this switching device. Find out how it works, what the principle of operation is based on, where to buy it and is it possible to make a similar switch with your own hands?

You can’t yet go in and buy a device like a clap switch at the first electrical goods store you come across. And not every manufacturer of household electrical appliances produces such devices. The most famous company that produces these devices is the Minsk company “Nootekhnika” of the Republic of Belarus. We will study the sound switch using the example of the Ecosvet-X-300-L switch developed by Belarusians.

Where is it used?

The cotton switch works with different lamps - fluorescent, incandescent, energy-saving, halogen, LED.

For its normal functioning, the voltage level in the network must be 220 V, the power of the lighting load should not exceed 300 W, and the permissible temperature should be from -20 to +40 degrees.

The cotton switch is no larger than a regular matchbox, so it can easily be placed at the base of any lighting fixture.

It is recommended to install the cotton light switch in rooms with a relatively low noise level. For example, in living rooms and storage rooms, basements and outbuildings. If these are some kind of office premises, workshops or production sites, where there are constantly extraneous sharp and loud noises, the device may trigger falsely.

It is best to install the cotton switch in the bedroom. If the room has only a chandelier with lamps and no bedside lamp, then after looking through a magazine before going to bed, you won’t need to get up to turn off the light, just clap your palms and it will go out.

And if someone still has switches located, as in the old Soviet times, at a height of 1.7 m, then a device that responds to cotton will become an indispensable assistant for children and people with disabilities.

There is also such a device as an acoustic light switch. The purpose and operating principle are the same as the cotton one, only it reacts not just to pops, but to any noise or even rustle. Such devices are most often used to illuminate the entrances of multi-storey buildings. While a person walks along the stairs or landing, rings the keys, opening the door, the light is on. As soon as people enter their apartments, the lighting disappears. Practical and economical in terms of energy consumption.

In general, you understand the essence; the main purpose of such devices is to turn the lighting on and off remotely (from a distance). They clapped their hands once (or made noise) - the light bulbs lit up, the second clap (or complete silence) accordingly turns off the lamp. With this everything is simple, but with the structural device and circuit it is more complicated.

This video demonstrates the operation of an acoustic switch:

Device

The simplest cotton switch has an electronic microphone in its circuit; in addition, an amplifier is installed with it in the form of two transistors connected to each other. These small details amplify any sound entering the microphone several times. Thanks to this, the switch can be activated even with a slight clap.

The amplified sound pulse is supplied to a powerful transistor, a relay coil is connected to its collector, the power circuit of which is connected to the lighting network. That is, the transistor controls this relay, and it, in turn, closes or opens the contacts in the lamp power circuit.

A capacitor is installed in the microphone circuit. You can select its capacity and thereby adjust the sensitivity of the microphone to the supplied sound.

simple acoustic switch circuit

The acoustic switch is designed on the same principle. The scheme works as follows. The sound captured by the microphone is converted into an electrical signal (voltage). The amplification cascade amplifies the voltage, in this form it is supplied to a powerful transistor, and from it to the relay coil. Current begins to flow through the relay, the magnetic core is retracted, thereby closing the power contacts of the relay in the lighting circuit. The light comes on.

Particularly experienced and competent electricians and radio amateurs will be able to assemble such a circuit on their own.

How to connect?

The cotton switch “Ekosvet-X-300-L” in question consists of a block in which the entire circuit is mounted, and two pairs of wires - white and black. The white ones need to be connected to a 220 V electrical network, the black wires are connected to the lighting load.

The lamp receives zero (directly) and phase (through an ordinary household switch) from the distribution box. These two wires are connected to the white wires. You can do this using the old-fashioned twisting method, but it is better to use special self-clamping terminals.

The black wires are connected to the lamp socket itself. That is, with the usual circuit, phase and zero from the supply network would go directly to the lamp socket, and so you also additionally inserted a cotton (or acoustic) light switch into this circuit.

The block itself must be secured to the body of the lighting fixture. The unit has a sensitivity regulator, with which you can set the desired level of cotton. It is most advisable to set the so-called medium level, so that it is not too light, otherwise the switch will start to operate at the slightest tap, and not too strong, so as not to knock off your palms.

The clapper switch is powered through a regular keypad mounted on the wall. If you need to remove a fancy sound device from the circuit, it will be enough to turn off the key switch.

All that remains is to experimentally test the results of your work. When operating correctly, Ecosvet-X-300-L will only respond to clapping of palms. Tap with a hammer, bring a running vacuum cleaner close to the lamp, beat it in a mug with a spoon, turn on a hammer drill, tease with a mobile phone signal. We don’t know what your experiments will show, but there have been cases when cotton switches were triggered by the sound of a working hammer drill or the ringing sound of a metal spoon hitting a mug. This is further confirmation that there are few ideal things in the world; any device, especially in electrical engineering, has, along with advantages, a number of disadvantages (even if completely insignificant).

"Сlaps" device

One of the newest developments is the “Claps” cotton switch model. In this device, the sound is processed using a microprocessor; it does not react to any extraneous noise, but is tuned to several claps in a row (this is the most important operating condition).

It is permissible to install several such switches in one room, each of them will react to a certain number of claps, and accordingly turn on the light, humidifier, fan, TV or stereo system. This switch model is suitable for any household appliances that have an electrical cord.

Perhaps to some, the clap switch may seem like a toy or a completely unnecessary device. Others, on the contrary, are passionate about the idea of ​​​​creating their own “smart home” so that lights and electrical appliances turn on and start working on command or clap. Arrange your life the way you want, but at the same time make it as comfortable as possible.

You can control lighting not only using classic switches, but also using special modules that allow you to turn the light on or off remotely. A cotton light switch is one of these devices; you can buy it at any electrical store and install it yourself.

Principle of operation

This acoustic switch operates on a special microcontroller that allows you to turn off the light by clapping your hands. Of course, such a control device can be used not only to control a lamp, but also many other electrical devices: fans, air conditioners, transformers.

The simplest sound switch consists of an electronic microphone in which a preamplifier is installed. Thanks to this part, any sound that enters the device is amplified several times, due to which even the smallest pops are perceived by the sensitive element. The operation of the amplifier itself is additionally controlled using transistors VT1 and VT2. The circuit is regulated by two resistors R2; rectifying diodes VD1 and VD2 are installed to level the signal.

When a clap sounds, the signal passes through the microphone and is amplified, after which it is converted into an electrical impulse. This pulse is equalized by rectifying diodes. The sound at which the light turns on is controlled by a resistor, i.e., if the sound of the clap does not exceed a preset value, the light bulb or other device connected to the switch will not turn on. After leveling the signal on the capacitor (indicated C8 in the diagram), the voltage increases, then the transistor switch VT3 opens.

Turning the light off and on is done by alternately discharging and charging the capacitors. After a full cycle of repeated clapping, the resistor and capacitor C10 will be discharged within 4 seconds, and the device will go into the off state.

Device installation

You can assemble a simple cotton acoustic switch with your own hands; it consists of the following parts:

1. Resistors;
2. Capacitor C12;
3. Diode bridge (say, VD7-VD10);
4. Transistors.

Please note that the capacitors must be at least 40 Volts. But not everyone likes to fold electronic devices themselves, so it will be easier to buy a cotton sound switch from the store. There you can choose a model to suit any needs and capabilities.

The installation of the cotton regulator is carried out according to the classical scheme, in which it is used together with a conventional one-key or two-key regulator. Each individual device has an individual connection diagram, but in principle they are all very similar. In short, you need to connect a single-key model to the network so that it powers the cotton one. How to do it:

1. The standard operating diagram of the switch and lamp is as follows: power is supplied from the panel through the distribution box to the standard switch. The neutral from the shield is led to a lamp (or several lamps). The lamps are connected in parallel to the disconnecting device;
2. You need to break the power circuit that goes to the key switch and install it on the acoustic one. It's very easy to do. The main advantage of such a device is its small size. There is no need to trench the wall, since such a controller is mainly installed on the lamp body;
3. As a standard, the switch has two pairs of wires: white and black. White ones are allocated for power, black ones for load. For example, white ones are connected to the phase and neutral cables from the panel, and black ones are connected to the lamps;
4. Individual cords can be connected using special terminals or a simple winding. Soldering the fastening points is not recommended;
5. After this, you need to turn on the regular key switch and check the operation of the system. If you need to completely remove it from the system, then reinstall the power wires so that they are connected directly to the cotton model.

It is very convenient that you can connect one switch for several lamps; it will control separate groups of devices. After installation, be sure to set the volume control to the desired level, otherwise the light will light up at the slightest clap or, on the contrary, will not turn on even with a strong knock. Most often, the regulator is a small rotary lever that needs to be screwed to the required level.

Video: features of the device of cotton switches

Price overview

You can buy a cotton switch in any city; the price of the device depends on the brand and its characteristics. Good reviews about Ecosvet, PIC (board 12F683), Claps and Qusun. Let's consider the cost of the Ecosvet-X-200-L model.

Another development of electronics was completed, after which mass production and sale of a new type of cotton switches immediately began. The cotton switch “CLAPS” reacts only to hand clapping, completely eliminates false alarms from extraneous sounds, it was specially designed for reliable remote turning on and off of lights and any other electrical appliances with ordinary clapping of hands. An interesting feature of this series of switches is the ability to place up to 4 such switches in one room, reacting to different numbers of hand-made claps. For example, the first switch responds to three claps, the second to four claps, the third to five claps, and the fourth to six claps. The required number of claps (to access a specific switch) must be performed in a row. The required number of claps to operate the switch is selected by simply moving the jumper on the electronic circuit board of the switch.

Thus, by clapping you can turn on and off not only the chandelier in the room, but also such frequently used household appliances as a fan or humidifier, a floor lamp or table lamp, a stereo or some other equipment. For example, with three claps of your hands you light a chandelier, and with four claps you turn on the fan. In this case, a switch configured to respond to three claps will not respond to a series of four claps. You can even open and close the curtains on the window by clapping - this is very mesmerizing for guests and brings a feeling of some kind of magic into your life - you just need an appropriate electric drive, but in our time this is not a problem.

Why do you need a smart home system? To constantly puzzle over how to turn on the light, to look for a lost remote control, or to carry out tedious system settings? With the CLAPS switch, simply clap your hands to turn the light on or off! You can buy a clap switch “CLAPS”, controlled by clapping your hands, right now in our online store. Currently, there are different types of cotton switches of the “CLAPS” series on sale, differing only in their housings (or lack of housing); their electronic circuits are the same.

An acoustic (or cotton) switch is an electronic device that is convenient to use at home. It is a device for remote control of lighting sources. You can turn the lighting on and off by clapping your hands by transmitting a sound signal to the acoustic device. Such equipment has some features, but it can also be assembled with your own hands.

Application of cotton switch

An acoustic (or clap) switch is designed to control electricity in various rooms remotely, that is, without directly touching the toggle switch. This device works by clapping your hands. In addition to lighting sources, the acoustic regulator can activate contactor coils, current converters, climate control systems and other electrical and electronic equipment - the main thing is that there is enough power.

Acoustic switches in residential areas

Sound switches are optimal for relatively quiet rooms in the house: bedrooms, libraries, offices, pantries, cellars. Installing such a device in the bedroom will allow you not to get out of bed to turn off the lights after you read your favorite book at night and get comfortable under the covers. To make the room plunge into cozy, enveloping darkness, you just need to clap your hands.

It is not advisable to install such devices in noisy places and rooms, since extraneous sounds will regularly provoke unauthorized activation of the device.

The cotton switch is very useful in everyday life for people who use a wheelchair, and it will also be useful for children.

As a rule, for safety reasons in children's rooms, electrical devices are placed at a height of 1.7 m. In order to independently turn on or off the light, the child has to stand on a stool, and this is also unsafe: the baby may lose his balance and fall. If you install a cotton switch, the child will not ask you to turn on or turn off the light every time. He will simply clap his hands and this will make the light come on or go out.

Interfloor space lighting Using a clap switch, you can control the light on the area between floors.

To do this, it must be equipped with a photo relay. The sensitivity of the motion sensor is controlled by a voltage divider with a resistor creating a photodiode. If using the motion sensor is not essential, you can disable it. To do this, you need to set the resistor to the lowest value.

When lighting the interfloor space, you can use the K176LA7 microcircuit. When using it, the automatic electricity activation device does not rattle at the upper and lower levels. Using an electret microphone, an acoustic wave is received and transformed into an electrical impulse. Then, through the use of three-electrode transistors, the pulse is received by the logical sections of the microchip, producing a signal lasting up to 10 seconds. During these 10 seconds, the lamp is in an activated, i.e., on state. To turn it off during daylight hours, you need to send a signal from the element’s output.

How does an acoustic switch work? The operating procedure of the cotton device is very simple: the first clap turns on the load, the second turns it off.

A fairly sensitive microphone receives an acoustic wave and sends it in the form of a signal to an audio frequency power amplifier. Next, the intense signal reaches the base of the switch, the value of which allows you to activate the transistor. The moment the base of the switch receives a pulse, the electron-hole junction of the transistor opens and conducts an electric current that powers the connected lighting fixture or relay that controls the loads.

http://zametkielectrika.ru/xlopkovyj-vyklyuchatel/

Technical characteristics of the cotton device

Light switches that are activated by clapping sounds can be found commercially or you can make your own. Let's consider the Ecosvet-X-200-L device, produced by the Belarusian company Nootekhnika. It has the following technical characteristics:

• load power - up to 300 watts;
• sound intensity - 30–150 decibels;
• mains voltage - 220 volts.

In addition to the switch itself, the kit includes a box and installation instructions. The price of this switch in comparison with similar devices from other manufacturers is quite affordable. The switch is produced in a protective housing class IP-30. It can operate at temperatures from -20 o C to +40 o C. This device can be combined with virtually any lamps: halogen, fluorescent, energy-saving, LED and standard incandescent lamps. The device is no larger than a matchbox, so it can be easily placed at the base of any light source. The switch is attached using double-sided construction tape or self-tapping screws.

Components of a sound switch

You can mount the acoustic switch yourself. Let's give an example using domestically produced KT315 transistors in a microphone amplifier. The final stage uses a high-power transistor switch based on the KT818 bipolar transistor. If you intend to control lamps with a power supply above 12 volts, then a relay is needed in the circuit. If the expected loads are less than this value, then the relay can be deleted. Copper wires are connected using Wago 222 terminals, which have their pros and cons.

Advantages of Wago terminal blocks:

• speed, accuracy and ease of connecting wires;
• electrical safety;
• no need to use special electrician tools;
• reliability;
• aesthetics and beauty.

Disadvantages of Wago terminal blocks:

• high price;
• The location of the nest is not very convenient.

Connection diagram and installation of cotton switch

Below is a diagram of the installation of the acoustic device “Ekosvet-X-300-L” into a light source with two compact fluorescent lamps, currently connected to a single-key toggle switch.

1. We connect white wires to a 220 V network without strictly observing polarity. We connect the load to the black wires - two compact fluorescent lamps.

   The load is connected to the black wires

2. We connect the white wires with phase and neutral, which come to the light source from the distribution box through the currently connected single-key switch.

   White wires are connected to a 220 V network

3. We connect the black wires directly to the lamps of the lighting device, connected in parallel to each other.

   Black wires are connected to the lamps of the lighting fixture

4. Temporarily turn off the existing single-key switch.
5. We set the sound strength we need by adjusting the perception control. We configure it so that the sensor is triggered by a not too strong, but not too weak cotton. If you need to clap very hard, you can hit your palms. If the sensor responds to too weak claps, the risk of false alarms will increase.

   The sensor on the device is adjusted using the perception regulator

Operating principle of an acoustic dimmer switch

An optical-acoustic switch is used for dimmer switching on electricity. It works as follows:

1. The sound signal (in our case it is a clap) arrives at the sensitive membrane of the microphone. There the sound is converted into an electrical impulse. When passing through the operational amplifier, the pulse power increases and the capacitor is charged. When the charge reaches a higher value than on the capacitance, the comparator switches. In this case, the zero at the output is replaced by a pulse from the logical section.
2. Such a chain is sequentially activated in the switch after receiving an acoustic signal from the microphone. Then the transistor generator is started, directing the electrical impulses, and the triac opens. Through it, power is supplied to the light source.
3. After some time, the capacitor loses voltage level. In this case, the triac receives control electrical signals with an ever-increasing phase delay, as a result of which the light turns off smoothly. With optimal selection of values, the light source turns off with a pause of up to three minutes.

Acoustic device test

The acoustic sensor for turning the light on and off is tested for the likelihood of activation from any sharp sounds and noises, except pops. As an experimental device, we will consider the domestically produced Claps Max switch. Let's check whether it will respond to sounds - from a hammer hitting a board, a switched-on impact wrench, a jigsaw and grinder, or the clicking of a screwdriver on metal. Such sounds may trigger the activation of the device.

Video: testing the Claps Max acoustic switch

In our version, the device did not respond to the sound of power tools turned on, nor to the sound of a hammer, nor to the clicking sound of a screwdriver. At the same time, it continued to respond to clapping its hands. This can be called an excellent result.

Self-assembly and installation of an acoustic (or cotton) switch should be carried out in compliance with safety standards. After testing the device for susceptibility, you can make adjustments to its settings.

To increase their comfort and simplify their daily routine, people are constantly coming up with new devices. Today we will look at a device for remote control of a payload using claps. A homemade cotton switch is useful, for example, for turning on the light in a vestibule or pantry, where usually finding the right switch causes a lot of inconvenience. For readers of the site, we will tell you in detail how to make such a device with your own hands, what parts need to be prepared for this, and what assembly scheme should be followed.

Assembly diagrams

All cotton or acoustic machines are united by the presence in the circuit of a microphone, which is needed to record sound. The design also provides an amplifier, trigger or to control the power switch.

In this circuit, operating from a 220V network, the signal from the electret microphone is supplied to transistor VT1 for amplification, then to the resistance matching unit and the emitter follower on transistor VT2. And then to the comparator and trigger, assembled on the K561TM2 digital chip.

A comparator is necessary to protect the switch from acoustic interference; it cuts off sounds that are too short or long. The signal that passes through the filter changes the state of the trigger (on or off), which in turn controls the load through a power transistor, relay and thyristor. It can be any lamp, for example an incandescent one.

Here is a diagram for assembling a homemade cotton switch with a similar purpose - on an integrated timer.

To make it easier to study the circuit, we have highlighted the main components on it: a microphone amplifier on the KT3102 transistor, a comparator on the ne555 chip, a TM561 trigger and a KT3102 transistor, which controls the power relay.

No less interesting will be the self-assembly of an acoustic relay on an Arduino microcontroller and ready-made modules for it, which will significantly simplify the understanding of the principles of operation for beginners and will allow you to fine-tune some operating parameters.

To make a cotton machine with your own hands, you need to prepare three boards:

• Arduino Nano;
• sound module;
• power relay module (note that it is 5 volts).

You also need a computer to download the firmware, a USB cable, and a 5-volt power supply (any phone charger will do). You need to install the Arduino IDE program on your PC to flash the microcontroller firmware. You can download it for free from the official website of the board developer.

By copying the text of the sketch (program) and pasting it into the Arduino IDE window, you can immediately flash the controller. By changing some parameters and rewriting the device, you can fine-tune your homemade sound relay for stable operation. As we can see from the diagram, four wires are connected to the controller: two for power. The yellow wire connected to pin 13 is for controlling the power relay. The control wire from the microphone module connected to the analog input A0 of the controller is marked in green.

The chip contains 8 analog inputs and 14 digital input/output contacts. For our project, we took A0 and D13, since together with it the LED on the Arduino board lights up, and you can clearly see when a signal is sent to the relay module.

Arduino sketch for making a sound relay:

By changing the x value in the if(analogRead(Al)>x) line, we set the sensitivity threshold, the maximum value of which is 1024. By making changes to the delay line, the delay period after the sketch is executed changes. This sets the readiness time for switching. In addition, the protective threshold against interference and false alarms is adjusted. In addition, the sensitivity of the microphone can be adjusted with a variable resistor on the board using a small screwdriver.

To test and configure the circuit, we took an Arduino UNO board based on the ATmega238 microcontroller. In this case, any other models are also suitable, since we do not use many board pins, and the sketch does not require high performance.

The video below clearly shows a homemade cotton switch, which we assembled according to the diagram provided:

Video instructions

Several simple ideas for making your own acoustic light switch are presented in the video.