Motion sensor for turning on the light - device, operating principle, connection diagrams

When we start talking about motion sensors, we must remember that there is some confusion in terms. The fact is that motion sensors themselves are devices for working as part of security systems. And motion sensors for turning on the lights are actually called light sensors, but in everyday life both devices are called motion sensors.

What is the main purpose of motion sensors to turn on lights? Comfort? Of course, but first of all, such sensors are installed to save energy. Thanks to them, electricity costs are reduced from 30% to 60%.

Their presence is relevant both in residential and non-residential premises, since the lights come on only when a living object appears in their area of ​​action. As soon as the movement stops, the light automatically turns off after a preset time. Also, the presence of sensors allows you to extend the life of the light bulbs, since they work less and burn out less often. Sensors are also convenient because the light will not be on all the time if you forgot to turn it off and left home or even left for a long time.

The principle of operation of the sensors is the same regardless of the manufacturer. But they may differ from each other in some characteristics, which need to be taken into account depending on the purpose of installing the device.

Which of the motion sensors offered by manufacturers for turning on lights can be considered the best on the market in 2022? By what parameters should you choose it and what should you pay attention to?

Where used, types

Products come in several types - ceiling, wall and for hidden installation. They are also conventionally divided into several types according to the principle of operation (we will discuss this in more detail below).

When choosing, consider the installation location. Sensors are divided into household and street lighting.

In the latter case, materials are used that protect the device from negative natural influences. It can be connected on the stairs or on the street. Household devices are designed for installation inside the house.

Depending on the circumstances, sensors that monitor movement can be connected to a spotlight, lamps, or even an Arduino smart home.

The main device manufacturers are ERA, Evan, TDM, LLT, Orbis, Duwi, Camelion, Brennenstuhl, Elektrostandard, FERON, REV, REXANT, Rubetek and others.

Setting up the detector indoors

Regardless of the location of the sensors, before setting up the system, you must carefully study the manufacturer’s instructions and its recommendations for adjustment.

The peculiarities of setting up the sensor indoors are that work or life requires a lot of illumination. So, in corridors the illumination should be at least 600 lux, and in work rooms at least 1000 lux. During the initial installation, you can use these numbers as a guide. The switching threshold should be higher - darkness sets in indoors earlier than outside.

Characteristics

When purchasing a motion sensor, it is important to consider a number of parameters, which determine the features, connection location, and conditions for use.

Main characteristics when choosing:

1. WEIGHT. Modern light sensors weigh from 25 to 240 g.
2. Maximum load power. When choosing a product, you need to look at the permissible load. Thus, one sensor can switch devices with power from 60 to 2300 W. Please note that when using more powerful devices, it may be necessary to replace the wiring or install a machine with a higher rated current.
3. VOLTAGE. The operating voltage varies in a wide range from 1.5 to 220 Volts. Conventionally, motion sensors are divided into several groups - 1.5 V, from 2.2 to 3.6 V, 220 V, 5 or 9 V.
4. MAXIMUM VIEWING ANGLE. Here the range is from 30 to 360 degrees. In the latter case, the device operates along the entire perimeter of the room.
5. RANGE. The minimum and maximum distance parameters are 8 and 120 m. Here you need to take into account the object on which lighting is provided. You should not choose sensors with an excessively high parameter, because they can react to the movement of strangers.
6. RECOMMENDED INSTALLATION HEIGHT. Here the permissible parameter ranges from 1.2 to 16 m.
7. PRESENCE OF LED INDICATOR. Some sensors are equipped with an LED that starts blinking when a signal is present. Other LED display options are also possible.

These are the main characteristics that you need to consider when purchasing. We will discuss the selection criteria in more detail below.

Scheme and principle of operation

There is a large selection of sensors on the market that react to movement and allow you to configure the switching on of lighting on different objects. When purchasing such devices, it is necessary to take into account the presence of several types.

Infrared

The products sense the heat emitted by the human body. The main element is a sensor with a Fresnel lens installed on it, which reacts to the approach of heat and bridges the contact group.

Operating principle:

• the radiation is focused into a narrow beam of light and directed to the sensor;
• the sensor detects the signal, receives it and gives a command to operate.

Such devices are conventionally divided into passive and active. In the first case, the response occurs to a change in temperature conditions, and in the second, the operation occurs in the event of a signal interruption.

Checking for correct adjustment

You can only check the correctness of the settings under operating conditions, and this process may take more than one day. At first, you need to carefully monitor the operation of the sensor and adjust the settings and location of the detector.

1. If the detector's photo relay turns on before it reaches darkness or does not turn off when the desired level of illumination is reached in the morning, its sensitivity to illumination (LUX) must be slightly coarsened. And vice versa, if it is already dark, and the light does not turn on when an object appears, you need to slightly increase the evening threshold of the photo relay. It's also a good idea to look at the trigger in the morning. The threshold values ​​for turning on and off are slightly different; this is done to eliminate multiple sensor activations at the edge of light and darkness (the characteristic has hysteresis). Therefore, it may take several days to reach a compromise result.
2. The same goes for sensor sensitivity. If you notice frequent false alarms from the appearance of small animals, then the sensitivity should be reduced by turning the Sens knob. If there is an uncertain response when people appear in the coverage area, the sensitivity must be increased.
3. The shutdown delay time adjustment (Time) can initially be set to a minimum. If during operation it is noticed that people or cars do not have time to leave the controlled area, then the response time can be gradually adjusted upward until the desired result is achieved.

Setup may take a long time, but it is well worth the cost.

Video tutorial on setting up the sensor.

Criterias of choice

When purchasing a presence sensor to turn on the light, it is important to consider a number of criteria regarding installation and operation features.

Let's highlight the basic recommendations:

1. DECIDE THE PLACE FOR INSTALLATION. For outdoor installation, it is advisable to choose devices with protection from IP 55 and higher (preferably from 65). If the product is mounted under a canopy and protected from water, IP 34 (44, 54) is suitable. If the motion sensor is planned to be installed inside, for example, to turn on lighting in a house, apartment or garage, there are no special requirements for the degree of protection.
2. CONSIDER POSSIBLE OBSTACLES (WALLS). The most commonly used sensors are sound or infrared sensors. Microwave products are more suitable for security purposes.
3. DECIDE YOUR VIEWING ANGLE. If the entrance to the room where the lighting is being adjusted is possible from several points, it is advisable to choose a sensor with a 360-degree angle and mounted on the ceiling. If there is only one passage, 180 degrees is enough.
4. DECIDE ON POWER. Before purchasing a device, consider the consumption of the devices that will be connected to it. Sum up the resulting values ​​and add 10-20% on top for reserve.
5. CONSIDER YOUR ACTION RADIUS. For a small room, a minimum parameter of 6-10 meters is sufficient. To work over a large area, it is better to choose sensors with a large radius.
6. PLEASE BE AWARE OF THE PRESENCE OF ANIMALS. If there are pets in the apartment or in the yard of the house that can affect the sensor, it is better to take devices with special protection.
7. PAY ATTENTION TO THE PRESENCE OF A PHOTO RELAY. This is a big plus, because in this case the product turns on only in the absence of light.

We will pay special attention to the choice of lighting devices:

1. When installing the sensor outdoors, use LED spotlights, which can easily withstand temperature changes and place less stress on the wiring.
2. In open areas, it is better to use lamps that operate on the luminescent principle.
3. When organizing driveway lighting, you can use all types of lamps, but in order to save money, it is better to choose the LED option.

Knowing the features of choosing a motion sensor and lighting elements, it is easier to make the right purchase and not make a mistake with the choice.

How to connect for lighting: on the stairs, in the apartment, on the street

There are five different connection schemes for lighting control. Let's look at the features of each option and common mistakes.

Circuits without a switch

To begin with, let's highlight circuit solutions that do not involve the use of a switch.

Two-wire connection

This is the simplest option, which involves the use of several elements - a 220 V circuit breaker, a sensor, a junction box and a lighting source). The principle of assembling the circuit is the same as when installing a lamp.

First, power is supplied to the indicator, and through it is directed to the lamp. It is better to assemble the chain in an individual circuit, rather than in a general lighting chain.

A simplified diagram is shown below.

Using this method, you can connect motion sensors to turn on the lights on the stairs, in an apartment or other object.

The action algorithm looks like this:

1. Place a cable with three cores and a 1.5 square wire into the junction box and label the wires (indicate the phase, ground and neutral wires).
2. Stretch two wires to the installation site of the control product, which gives the command to turn on the lighting.

3. Place the device at a height of 120-200 cm from the floor. When installing, make sure that it does not interfere with the opening of doors or other mechanisms. It is not recommended to install near heating elements.

4. Also place the cable that goes to the light source in the box.
5. Connect all the wires using special terminal blocks - phase, neutral and ground.

6. Connect the wires to the sensor. Place the phase on the terminal with L, and the second wire (from the lamp) on the load symbol.

7. Finish the installation by installing the box and setting it up. Set the automatic mode, operating time interval and sensitivity level.

How to avoid false positives

To avoid false switching on of lighting in the circuit solutions discussed above, follow these tips:

1. Do not place sensors near trees or heating devices.
2. Always break only the phase.
3. Make sure that light rays, for example from an incandescent lamp, do not penetrate to the sensor.
4. Attach the product depending on the type (wall, ceiling).
5. Do not install the device near air conditioners or windows where there is air movement.
6. Make sure that the glass of the infrared product is clean and undamaged.

Following the above tips allows you to quickly and without errors connect a device to control lighting on the stairs, in an apartment or on the street.

How to install DD to turn on the light: 2 main schemes

It is recommended to install the sensor-lamp system separately from general lighting. In order for the DD to turn on the light to work instead of a switch, a separate line is installed where only the device and the lamp will work. But often it becomes necessary to include a switch in this circuit. This will allow you to turn off the lighting if necessary.

In the photo: a) connecting the sensor without a switch; b) connection with a switch.

How to connect to a spotlight

Another issue that requires consideration is how to properly connect a motion sensor to a floodlight.

To do this, you can use one of the following schemes:

1. WITH THREE CONTACTS. In this case, the phase is supplied from the shield to terminal L. From output A, the wire goes to the input L of the spotlight. Voltage is supplied when the motion sensor is triggered. Contacts N are combined and directed to the shield. The ground is sent directly to the spotlight and connected to the PE to remove possible voltage from the metal housing.

2. USING A SINGLE KEY SWITCH. In the solution discussed above, the use of a switch is not provided. But this can be fixed. As a rule, the switch is mounted in a phase break (before the product that controls the movement). In this case, when the switch is turned off, the voltage is removed from the entire circuit. The second option for connecting the switch is parallel to the phase and the output of the motion sensor. With this solution, you can turn on the lighting without being tied to other devices. When the switch is turned off, the entire circuit operates as usual.
3. USING A TWO-KEY SWITCH. In this case, a certain symbiosis of the two circuit solutions discussed above is introduced. One contact of the switch breaks the phase, and the second comes in parallel. When both buttons are disconnected, the voltage is completely removed from the circuit. When the first key is turned off, the sensor operates in normal mode and turns on the spotlight when movement occurs. If only the second key is activated, voltage is immediately applied to the lamp.
4. TWO SENSORS. The same principle applies here as discussed above. Two movement-controlling organs are arranged in parallel, after which they are connected to the power circuit and the spotlight.
5. CONNECTING THE LAMP TO A LOWER VOLTAGE. If it is necessary to turn on the spotlight at a lower voltage (12, 24 or 36), a power supply is installed in front of the input, reducing 220 V to the required level. In this case, three wires (with ground) are supplied to the power supply input; only power is sent to the sensor.
6. FOR A SEPARATE PHOTO RELAY. When installing old motion controllers without a photo relay, the latter must be connected separately. In this case, the wire goes from the output of the sensor to the relay, and after that to the input of the spotlight. The zeros are combined and the ground goes towards the light source.

Above are the basic diagrams that allow you to connect a spotlight with or without a switch. Here everyone makes a decision taking into account the current tasks and characteristics of the room.

How to connect to Arduino

Of no less interest is connecting a motion sensor to Arduino to organize a smart home.

To solve the problem you need to prepare:

• Arduino board;
• PIR motion control device;
• solderless breadboard;
• 220 Ohm resistance and LED;
• wires of the male-male and male-male types.

The name of the contact connections may differ from one manufacturer to another, so before performing work it is necessary to study the features of the module.

One pin is connected to GND, the next to VCC (5 V), and the remaining one to OUT (transmits a digital signal from the PIR sensor).

PIR sensors are almost identical in design. They have the necessary sensitivity at a distance of up to six meters, and visibility is 110*70 degrees. The output appears 0 or 1 depending on whether the fact of movement is detected.

Can I do it myself?

Despite the low price of sensors, many people try to make the devices themselves and save money. The advantages of such a solution are the ability to thoroughly understand the principle of operation, reduce maintenance costs and “tailor” the device to specific application conditions.

In addition, with proper assembly, you can reduce costs and even upgrade the system.

But there are also disadvantages. Before you start work, you need to purchase equipment, draw a diagram, decide on dimensions and other points. This requires experience and knowledge. However, there is no guarantee that the finished scheme will work.

If you decide to assemble the motion sensor yourself, prepare the following items:

• circuit assembly housing;
• set of elements;
• soldering iron and wires of different sections;
• fastening;
• screwdriver;
• other materials - electrical tape, pliers, cambric.

To turn on the lighting, a sensor with a photocell built into it will be used. A photo relay will act as a switch.

To collect the diagram you will need:

• capacitor (C1);
• operational amplifier DA1;
• phototransistor (VT1);
• resistance R1 to load the collector and create an operating point;
• resistor R2 to implement feedback.

When assembled correctly, the circuit works like this. After light enters VT1, the element is triggered and the phototransistor opens, followed by charging C1. When the voltage is removed from VT1, the capacitor discharges and the voltage decreases.

The light source for the photocell can be a simple laser or an infrared LED.

The assembly proceeds according to the following algorithm:

1. Assemble the power supply, adjust it and monitor the current output.
2. Connect a resistor to the negative of the power source.
3. Connect the diode using the cathode.
4. Connect a tuning resistor to the anode.
5. Connect the transistor emitter to the negative wire of the power supply.
6. Connect the resistor to the base circuit.

After assembly, all that remains is to test the correct operation of the product when light hits it. Possible errors must be eliminated immediately upon detection.

Parameters to be configured

Other sensor parameters can be adjusted to suit specific local conditions. This will help optimize the operation of the lighting system and minimize false alarms.

1. First choose the correct installation angle.
   It is configured in such a way that the object is detected immediately upon entering the controlled area. Options for correct and incorrect setting of the control angle.
2. Secondly, the sensitivity of the sensor is adjusted (the adjustment element is designated SENS from the word sensitive). The essence of this adjustment is to tune out triggers when small objects are detected. In most cases, these are small animals; there is no point in turning on the lighting for them.
3. Most sensors are equipped with a photo relay. Without it, the sensor will also work during daylight hours, or they will have to be turned off manually. The response threshold of the photo relay must be adjusted so that the detector does not waste electricity during the day, but turns on the lighting in time at night. The adjustment control is marked LUX or Day Light.
4. Many models have the ability to configure a shutdown time delay. This is convenient when leaving the territory - the light will not go out immediately, allowing a person or car to leave not in complete darkness.

Not all detectors have a full set of settings. Some inexpensive models may not have a response time setting, while others may not have sensitivity to the size of objects.

An example of the location of the controls for an infrared motion detector

Possible problems

Other reasons may also lead to false alarms and incorrect operation of the sensor, which we mentioned above:

1. Installing a wall sensor on the ceiling. If such an error was made, the device will not work correctly because the viewing angles are different.
2. Random activation of the sensor after it has been turned off. This often happens with IR products when there is a light source next to the device, the beam from which directly hits the sensitive element. Therefore, it is important to place it away from lighting fixtures.
3. The influence of drafts, wind and glare. The sensor cannot be mounted on air conditioners, above windows, or in corridors where there is a strong draft. Above places where water accumulates and where direct sunlight falls. Reflected glare hitting the sensitive element of the sensor will lead to its frequent operation.

Connection diagram for D. movement for lighting without a switch: 2 installation methods

Manufacturers now offer users two types of DD: ceiling and wall. Their operating principle is similar, but the model must be selected individually, taking into account the installation location.

Ceiling devices are capable of covering an area within a 360° radius and their protected area in the diagram looks like a cone, where the rays diverge by 120°. When a person enters the sensor’s visibility range, he crosses the multi-beam barrier, which is detected automatically, and puts the sensor into alarm mode.

Ceiling devices are installed at a height of 2.5 to 3 meters. They are capable of covering an area in the lower part of the room with a diameter of up to 20 meters. It is advisable to install such equipment in small rooms in order to simultaneously monitor all aspects of the room.

Wall sensors can cover a large area of ​​space. The device is used not only indoors, but also outdoors. It also completes the electrical circuit when a person crosses the multi-beam barrier. The equipment is installed at a height of 2 to 2.5 meters. It is recommended to mount the sensor in a corner of the room. In this position, the opening of the rays is most effective.