How does a motion sensor work for lighting? Select a street motion sensor to turn on the lights. Working principle of a microwave motion sensor

A motion sensor for turning on the light is a device that responds to the movement of humans and animals in the tracking zone. When the sensor is triggered, it turns on or off the light, as well as other devices.

How to choose a motion sensor

There are many options for dividing sensors into categories, based on the features of a particular design.

At installation location:

• outdoor – intended for installation outdoors, they have a degree of protection IP44-IP65;
• internal – intended for installation indoors.

Based on the operating principle:

• ultrasonic – triggered by ultrasound;
• microwave – emit high-frequency radio waves;
• infrared - captures thermal radiation.

Active sensors have a signal receiver and transmitter; passive sensors do not have a transmitter.

By device:

• single-position - the receiver and transmitter are mounted in one housing;
• two-position - the transmitter and receiver are installed in different places;
• multi-position - a system with several transmitters and receivers installed in different places.

By installation type:

• multifunctional – monitor the level of illumination and movement;
• indoor – installed indoors and connected to security or lighting control systems;
• street motion sensors - used to turn on street lighting and protection of the territory;
• overhead – designed for wall mounting;
• ceiling - mounted in a suspended ceiling;
• mortise – can be built into walls and furniture; they look like a miniature interior detail.

Presence sensors

The most sensitive detectors are called “occupancy sensors.” They react not to the movement of a person around the room, but to the movement of parts of the body - arms, legs or head, which occur constantly, except for sleep.

Such devices control the light in the office, bathroom or toilet.

Power type

The sensors are powered from a 220 V network. In some wireless models that have signal transmission using radio waves, power is supplied from built-in 12 V batteries.

Advantages and disadvantages of use

Motion sensors are very convenient devices. They can be used in different situations:

• Security systems. They increase the security of a facility by complementing the surveillance of security guards or making it possible to do without them.
• Automatic power-on control m lighting paths, stairs or entrances. DD helps save energy by turning off lights in unused areas. household premises and outdoor areas without people.
• Organization of an autonomous security system garage or cottage. The sensor signal will turn on the light and siren and scare away the thief.

But besides the advantages, the devices have disadvantages:

• Probability of false positives or lack of operation in necessary cases. These cases can be minimized by using combined sensors.
• Price. All electrical appliances have their price, and combined sensors are more expensive than conventional ones. But their use pays off in energy savings or increased security of the protected facility.

Method for determining the presence of motion

The sensor detects the presence of motion by analyzing signals various types, coming from the direction of the observation zone.

Ultrasound devices

Ultrasonic motion sensors work on the principle of a locator bat— emit ultrasound and pick up the reflected signal. When it changes, it triggers.

Inside the sensor there is an ultrasound generator with a frequency of 20–60 kHz. The reflected ultrasound is received by the receiver. When objects move in the sensor's control zone, the signal frequency changes due to the Doppler effect. These changes are processed and, if the set level is exceeded, trigger the actuators.

Such devices are widely used in automatic parking systems, monitoring car blind spots and reversing sensors, for example, Fiat 124–13, as well as indoors, in long corridors and on stairs.

Advantages of ultrasonic sensors:

• low cost;
• no influence of weather;
• remain operational when high humidity and dustiness;
• does not affect the material of the moving object;
• drive away the mice - at first, after switching on, there are frequent false alarms, and after a while they go away and the signals stop.

Disadvantages of ultrasonic devices:

• Ultrasound causes discomfort in pets. It is even used as a dog repeller.
• Short detection range.
• Works only on fast movements - it is easy to deceive with slow ones. You can adjust the sensitivity so that it triggers when the slightest movements body, but this will increase the number of false signals.

Infrared devices

The operating principle of such devices is based on changes in thermal radiation when objects move.

All objects with a temperature above absolute zero (-273 degrees) emit infrared, or heat rays. This radiation is captured by a system of lenses or mirrors, the number of which is from 20 to 60. The rays, passing through this system, hit the sensor.

There are two sensors in the body of the device that monitor the temperature in different zones. If there is no movement in the protected area, the signals are the same and do not change. When a heated body, for example a person, moves, the signals on the sensors differ from each other, which causes the device to operate.

Expert opinion

Alexey Bartosh

Specialist in the repair, maintenance of electrical equipment and industrial electronics.

Attention! Maximum sensitivity is achieved when the object moves along the sensor, from right to left and vice versa.

This must be taken into account in order to avoid dead zones. For example, to control a corridor or door, the device must be installed so that it front part was directed across the aisle.

Advantages of the infrared sensor:

• fine adjustment of the control zone;
• on the street does not react to swaying trees, but indoors to curtains;
• does not emit anything during operation and is harmless to humans and animals.

Disadvantages of IR sensors:

• false alarms due to warm air from air conditioners and heating radiators are possible;
• when hit sun rays and during precipitation, the accuracy of work on the street is reduced;
• narrow operating temperature range – at high temperature thermal radiation from people and animals merges with radiation from surrounding objects, and at low temperatures, skin and clothing cool down and the radiation is too weak;
• you can hide from the sensor behind a screen or in a suit that does not allow heat rays to pass through.

Microwave sensors

Operating principle and device microwave sensor similar to ultrasonic - it emits high-frequency electromagnetic vibrations and receives the reflected signal. The most common radiation frequency is 5.8 GHz.

The device is triggered when the frequency of the reflected signal changes. When objects move in the control zone, the Doppler effect occurs and the frequency of the reflected signal changes. These changes are processed by the microprocessor and the device is triggered.

Advantages of microwave sensors:

• control of the territory is not hampered by thin dielectric partitions brick walls, wooden doors and windows without bars;
• wide operating temperature range;
• high sensitivity;
• several independent control zones;
• compactness.

Disadvantages of RF sensors:

• more expensive than other types of devices;
• false alarms for movement outside the surveillance zone - outside the window or thin walls;
• Microwave waves are harmful to health, so their power should not, according to WHO (World Health Organization) requirements, exceed 1 mW/cm2.

Combined instruments

Combination devices combine sensors different types, for example, infrared and high frequency. In such devices, the disadvantages of some types are compensated by the advantages of others.

The disadvantage of such devices is that they are more high price compared to conventional devices.

Main technical characteristics

When choosing a device, in addition to the type of sensor, the technical characteristics of the device are important.

Viewing angle

When choosing an installation location, it is important to consider the viewing angle.

Ceiling sensors have a viewing angle of up to 360 degrees. When installing it on the wall, half of the capabilities will not be used (infrared and ultrasonic DD) or false alarms will appear (HF sensor).

The viewing angle of the wall sensor is 180 degrees. Such devices monitor the area in front of the entrance.

Range

Control distance is equally important. An attempt to increase it by hanging the device higher than what the manufacturer intended will lead to the appearance of blind spots. The radius of the control zone ranges from 6 to 50 meters. Therefore, to turn on street lighting, the sensor range must correspond to the size of the territory.

Power of connected luminaires

The load power that can be connected to the device also has great importance. It is determined by the power of the lamps or luminaires that are connected to it. In addition, it is necessary to provide a 20% power reserve.

If the power of the device is insufficient, the lamps can be turned on via a relay or starter.

Additional functions

In some situations, just recording movement in the control zone is not enough. In these cases, you need to purchase a device with additional features:

Installation method and location

All types of sensors are available in two types, differing in installation location - ceiling-mounted, with a viewing angle of 360 degrees, and wall-mounted, with a viewing angle of 180 degrees.

The sensitivity and reliability of ultrasonic and microwave sensors is maximum when the object moves towards the device, and infrared sensors - across the control zone. This must be taken into account when choosing the installation location.

Installation of ceiling sensors

Ceiling sensors are installed at a height of 2.5–3 meters. The control area in this case has a diameter of 10–20 meters. They are installed in a room where they control the entire space.

Installing Wall Sensors

Wall models are used both indoors and outdoors. The operating range of such devices is up to 50 meters. Installation height – 2–2.5 meters. Indoors they are most often mounted in a corner, and outdoors - on the wall of a building.

When using devices outdoors, it is necessary to use all-weather devices with a degree of protection IP54–IP65. IP44 is allowed under canopy.

Adjustment (setting)

The motion sensor can be installed with factory settings, but if its parameters are adjusted, it will work better and more reliably, which will save energy or increase safety.

Tilt angle

First of all, you need to set the detection zone. To do this you need to select correct angle tilt The body of the device has hinges that allow you to adjust the position.

If tilted incorrectly, blind spots may appear.

Sensitivity

In addition to position, sensitivity adjustment is of great importance. It is produced by a wheel or handle with the inscription “SENS”. The minimum sensitivity is indicated by min (low or –), the maximum – max (high or +).

The setting is made so that the device works on humans, but not on animals. To do this, the regulator is set to the position of maximum sensitivity and, by gradually decreasing, the optimal value is searched.

If he lives in the house big dog, then setting up the device so that it reacts to people, but does not react to her, will not work.

Light level

If the DD is connected to a lighting control system, then it is necessary to configure the light level sensor. It is designated "LUX".

To adjust, in the evening it is set to the position of maximum sensitivity, and it decreases until the sensor is triggered.

If there is no built-in sensor, you can connect an external one. Its setup is done in the same way.

Delay time

Another important parameter is the shutdown time delay. The regulator responsible for it is designated “TIME”. This value varies from 5 seconds to 10 minutes.

When setting up, it is better to set the minimum value and gradually increase it to a comfortable value.

Review of manufacturers and prices

Motion sensors include:

• 
  IEK DD 010. This is a wall-ceiling infrared sensor, the degree of protection from weather conditions is IP44, which allows it to be used outdoors under a canopy. The observation range is 10 meters, the lamp power is 1.1 kW. You can buy it for 399 rubles. This device is made in China guarantee period 1 year.
• Feron SEN50. This 500 W device is built into the ceiling, the control angle is 320 degrees. The device has a light sensor with an adjustment limit of 3–2000 lux and a shutdown delay from 5 seconds to 7 minutes. The device is installed at a height of 2.2–4 meters. Degree of protection – IP44. You can purchase the device for 475 rubles. The Glowbowl motion sensor is installed in the toilet. This device includes LED backlight internal parts and eliminate the need small child look for the switch at night. Power is supplied by three AAA batteries. You can buy it for 650 rubles.

In addition to choosing a separate model, you can also select a manufacturer. The most famous among them:

• Odeon Light– Italian company , known for its beautiful designs and good quality.
• Italian Holding "LIGHTSTAR GROUP" Known for premium products for over 20 years. The holding includes two brands that produce lighting equipment – ​​“Lightstar” and “Osgona”, as well as furniture “Carpenter by Lightstar Group”.
• Italian company Artelamp. The main activities are production and distribution of interior lighting products. The company operates in 20 countries, including Eastern Europe.
• TM Camelion. JSC Energy Systems and Technologies (JSC EST) supplies products under this brand.
• ESYLUX company. Located in the city of Ahrensburg (near Hamburg, Germany).

Motion sensors are convenient modern devices, which, if selected correctly, allow you to automate light control and home security, and can also be used in the “ smart House».

When purchasing a motion sensor to turn on the light, you should not take the first one you come across. To begin with, you should determine some significant parameters, the conditions for its future use, and depending on them, select a sensor with suitable technical characteristics. There are four main parameters, taking into account which you will not go wrong and will not be disappointed; these are the parameters:

environmental conditions;

power of switched equipment;

features of the response zone: the required viewing angle and range of the sensor;

requirements for sensor response time and light level adjustment.

For different conditions environment, sensors with different degrees (classes) of protection are provided. The protection class shows how resistant the sensor housing is to dust and other physical influences, how protected it is from moisture, and therefore whether it can operate normally in rain or snow, etc. Thus, the most common motion sensors are the following protection classes: IP20 IP40 IP41 IP44 IP54 IP55.

IP20. A sensor of this protection class can operate reliably in dry conditions. indoors, that is, where there is no risk of moisture getting on its body. The body of such a sensor will withstand accidental touches, but the ingress of sand, for example, can damage it.

IP40. Such a sensor is protected from possible contact with sand and small particles about 1 mm in size, but is not protected from moisture, that is, it is again applicable only in dry rooms.

IP41. There is already protection from moisture here, i.e. the damp space of the room will not pose a threat to normal operation sensor If during operation even drops of condensate fall on the sensor body, its operation will not be disrupted.

IP44. The housing of such a sensor is protected from splashes; it can be used even in rooms with high humidity and on the street, for example, it is already protected from rain.

IP54. This degree of protection indicates that the sensor housing is protected not only from splashes, but also from settling dust, i.e. Even if some dust gets inside the sensor housing, its operation will not be affected.

IP55. In addition to protection from dust, the degree of protection from moisture is higher; even jets directed at the sensor are acceptable.

Once the required sensor protection class has been determined, it is important to pay attention to maximum power, which the sensor can switch. It's one thing to turn on a low-power LED spotlight or fluorescent lamp, and quite another thing is switching a lighting system, for example, a production workshop.

Having known in advance the power of the lighting equipment to be switched on, you can easily select suitable model motion sensor. The maximum switching power of such sensors usually ranges from 60 to 2200 W.

The ergonomics of a lighting control system determines not only the nuances of convenient use of devices. This is also a means of saving energy, which is achieved through balanced control of operating modes. In this regard, systems are becoming increasingly popular automated control lamps that do not depend on the owner himself. Having configured the network according to specific parameters, you don’t have to worry about regulating the work process - it will be under the control of the electronics. The most common control tool of this type is a motion sensor to turn on the light. A photo of a street model of this device is presented below. This is a standard design of the detector, the design of which is equipped with basic external protection shells.

Design and principle of operation of the sensor

Externally, such devices resemble small plastic boxes containing sensitive elements. The device is attached to the point where a person is expected to pass. For example, at the gate, near the landing, on the porch, etc. When approaching the serviced area, the sensor detects the approach and gives a signal to close the circuit, after which the lamp automatically turns on. Spotlights, lanterns, backlights, shades and other lighting devices are used as target controlled equipment. Depending on the settings, the street motion sensor can withstand a certain pause before closing the circuit to turn on the light. This opportunity is justified if the owner needs to walk a few meters to the place where the device will be turned on. A small delay will save a small amount of watts, but over the long term it will add up to significant savings. The basic choice should be made based on the operating principle of the above-mentioned sensitive element. Depending on the method of reacting to movement, such sensors are classified into several types.

Ultrasonic models

The principle of operation is based on changes in the parameters of the ultrasonic wave that the device produces. The design provides a sensitive element in the form of an emitter with a frequency range of 20-60 kHz. The wave propagates in the serviced area and when it collides with a moving object, the signal is received back and subsequently activated. Affordable cost and independence from air temperature are the main advantages of such motion sensors for turning on lights. The outdoor use of ultrasonic models is also advantageous in that they are characterized by low sensitivity to external factors. That is, an accidental entry of a sheet into the coverage field of the reacting wave will not lead to a false operation of the lighting device. On the other hand, animals may experience anxiety from the effects of ultrasound, and an attacker, if desired, will be able to “bypass” the sensor by moving smoothly.

Infrared sensors

In this case, the device reacts to thermal radiation. For this purpose, an appropriate optical filling with lenses and a sensitive sensor is provided that captures infrared waves. Depending on the power of a particular device, the number of lenses can be 20-60 pieces. Therefore, the more there are, the further the signal reception zone will spread. TO strengths Such devices include a wide viewing angle and range - street motion sensors for turning on lights based on optical sensors can serve a radius of more than 10 m with 360-degree scanning. But exactly high density capturing the target zone causes a serious disadvantage in the form of a large percentage false positives. Classic example- This is the effect of sunlight on infrared receivers. But the harm to animals and humans from such detectors is minimal.

Microwave models

The response, as in the case of ultrasonic devices, occurs as a result of changes in the parameters of the wave radiation. As a rule, sensors are used that provide microwave dissipation with a power of 1 mW/cm 2. This allows detectors to not only scan a target area for movement, but also detect people behind partitions, doors, and even thin walls. The quality of the reaction does not depend on weather conditions and temperature regime. What will you have to pay for such advantages? Microwave street sensor movements to turn on lighting equipment are expensive, but most importantly, there are potential risks negative influence on human health from the effects of such radiation as such. In order to minimize harm, experts recommend household needs purchase models entry level with low performance.

Combined devices

As the name suggests, it is in some sense a hybrid based on several sensors. In particular, we are talking about combining two radiation sources - ultrasonic and microwave. The result of the combination made it possible to eliminate some of the shortcomings characteristic of each of these scanning technologies separately. So, the weak points were eliminated operational process in the form of a high percentage of false positives and low accuracy. As a rule, these are more flexible and in terms of installation motion sensors for turning on the light. The street method of their use is fully justified both in terms of physical security and in terms of wide possibilities connections to different types lighting equipment.

Key Features for Selection

The primary operating parameters are the already mentioned operating range and coverage angle indicators. The minimum radius is 4-6 m. These are devices that are suitable for narrow passage areas, landings and small openings. The maximum distance can reach 20-25 m - the optimal characteristics of street motion sensors for turning on the light in the open area in front of the cottage. As for the viewing angle, it is selected taking into account the specific conditions of use. The freer the space, the wider the angle should be - from 60 to 360 degrees.

Special attention is paid to the protective qualities of the device, since it will be used on outdoors with all weather threats. At a minimum, the security class must correspond to the IP54 marking. This designation indicates a high degree of dust and moisture insulation. But it’s best to immediately focus on a street motion sensor to turn on the IP65 light, which also has a reliable shell in case of targeted physical impact. The case is provided with an impact-resistant coating with a full set of water-, dust- and frost-resistant layers.

Reviews of RANEX models

The company offers standard, but at the same time high-quality and functional versions of sensors for any street lighting system. Users of sensors of this brand note their design advantages in the form of strength, reliability and durability, as well as ergonomic control and flexibility in settings. For example, many praise the RANEX street motion sensor for turning on lights for its ability to withstand temperature loads in the range from -20 to 60 ° C without losing the accuracy of object fixation. In terms of cost, this is also a very attractive option. For 600-800 rubles. you can find a suitable device for a country home.

Reviews of Brennenstuhl models

Devices in this line are more oriented towards commercial use, but private owners often purchase them due to their high reliability. Also among positive sides Operations of the control electronics of this company note a small proportion of false alarms, the possibility of implementing an autonomous power supply and operating range. For example, a street motion sensor for turning on lights at 20 meters with infrared sensors is capable of serving a completely open area with maximum visibility. If necessary, some models can be reconfigured, specifying the coverage spectrum and radius. According to users, this makes it possible to make the operation of the device invisible to animals.

A motion sensor is a device that detects the movement of objects.
In everyday life, this is an electronic infrared sensor, the task of which is to detect the presence and movements of a person in the space that he controls.

Scope of application

When motion is detected, it generates a control signal, which triggers the established algorithm of actions and connects power to electrical devices, most often lighting.

Mainly used for the following purposes:

• Security (for example, starts a video camera);
• Signaling;
• Control of access to premises;
• Lighting control;
• Smart home system control (controls lighting, ventilation, air conditioning, heating, opening automatic gate(doors), and other mechanisms depending on the presence or approach of people).

Advantages of using motion sensors for lighting:

1. Saving 50-80% of consumed electricity.
2. Convenience
3. Save time and effort - the light turns off automatically
4. Automatic switching on. This is the main advantage. Now you don’t need to stumble near an unlit house or fumble for the light switch for street lighting
5. Safety. Excellent system for repelling uninvited night guests, also prevents accidents on the stairs in the dark
6. Hospitality: it's nice when the lights turn on when approaching the house
7. Ability to control ventilation in toilets and bathrooms
8. The light turns on only when insufficient level illumination.

Types and features

When choosing a motion sensor, you need to know and take into account their variety of characteristics, which are designed to maximize the efficiency of using the device in a particular case.

Device device

Here is a fairly extensive list of varieties:
Type of radiation used:

• Microwave;
• infrared;
• Combined;
• ultrasonic;

Location:

1. Outdoor perimetric;
2. Peripheral;
3. Internal;

Location method:

• Ceiling (360 degree view);
• Wall-mounted;
• Corner (most convenient way installation);
• Universal (includes fasteners for all different locations);

Control method:

• Automatic;
• Forced shutdown option;
• Operation range adjustment function;
• Remote;

Operating principle of the device

IR motion sensors detect changes in thermal (infrared) radiation. Each object has its own temperature and emits an infrared spectrum. The radiation from the object is alternately focused through lenses or mirrors onto a sensor, which registers it and this serves as a signal to trigger the necessary actions.

Microwave (microwave) motion sensors: The microwave motion sensor emits electromagnetic waves (frequency 5.8 GHz). They bounce off objects and return to the sensor. The Doppler effect is used - a change in the frequency of a wave that is reflected from moving objects. If changes in reflected electromagnetic waves are detected, the device processor activates the required action algorithm.

Operating principle of combined devices. These motion sensors combine several types of motion detection. Used when precise recording of movements is necessary. Parallel motion detection technologies make the sensor work as efficiently as possible, as they complement each other, replacing the shortcomings of one technology with the advantages of another.

Main selection criteria

When choosing a motion sensor for lighting, pay attention to all the specifications of motion devices shown, the disadvantages and advantages of sensor types.

Choose a model taking into account:

1. External or internal use?
2. Actual installation location? (near or inside the house, pillar, wall, corners, ceiling, size of the sensitivity zone). This criterion determines the coverage angle and the number of sensors.
3. Degree of protection from the external environment.
4. Installation method.
5. Power of connected equipment (W).
6. Relationships between active and passive zones, obstructions to view.
7. Trigger zone and detection radius.
8. Nature of application. For example, in schools it is recommended to install devices at a height inaccessible to children.
9. Additional push button switch to control lighting manually.

Having chosen a model, build a communications system for it and prepare the installation site. Motion detectors outside the house need protection from outsiders. The housing must be hermetically protected from dust and moisture, the level of protection is measured from IP 20 to IP 55.

pay attention to temperature Range, permissible for operating the detector.
Use wireless standalone devices, if laying cables is impossible for some reason, or will be located far from home.

Choose combined sensors if there are a lot of interfering objects in the scanning area.
Some lenses leave a blind spot a meter above the floor to avoid taking into account the movements of pets. The device has a detection radius specified by the manufacturer. Do not try to increase it by fixing the device higher than specified in the specification, as this will only reduce the efficiency and even create “blind” spots.

The correct operation of the most popular type of device, with an infrared sensor, most depends on external factors: size and intensity of thermal radiation of the object; temperature difference between the object and environment(the greater the difference, the further the detection distance); weather conditions: snow, rain, fog; direction and speed of movement of the object through the scanning area. So it’s up to you to decide whether to install the IR device outside the house, on the street.

The price of products on the current market is the most varied - starting from just $3 and up to the sky-high, but not the maximum, $200. We recommend not choosing the cheapest ones, since their service life is short and you will have to buy new ones often. Against this background, the more expensive ones are much more economical.

Proper placement of devices

There are a huge number of different motion sensors and each of them is designed for a specific task: to start a pump from a fountain, to illuminate a pool. Consider the size of the space, the placement of windows and doors, because all this affects the correct operation of the device.
When connecting the device, consider the following nuances:

1. Pollution.
2. Any obstacle in the controlled visibility area (trees, bushes) can lead to a false alarm.
3. Outdoors, use waterproof wires.
4. Do not install the sensor in front of devices that emit light or electromagnetic radiation.
5. Works only at a given angle and in a given direction.
6. Select lamps according to power, with a margin of 15%.

If the sensor does not cover the entire territory, use a connection diagram for 2 or more movement clamps and a street lighting fixture. Sometimes you need to connect several powerful light bulbs (to illuminate the yard), then use magnetic switch.

Install a magnetic starter between the sensor phase and the lamp, and its coil on the other side of the lamp. Fixed field of view models are installed in convenient location, but always with the doors in their field of view, then the light will turn on when they open.

Very useful device

Motion sensors for lighting control have become extremely popular today. Used in the most incredible institutions and places: hotels, offices, administrative buildings, educational institutions, gyms, parking lots, retail establishments, bathrooms, swimming pools, fountains, on the roadway and sidewalks.

The motion sensor is electronic device, which determines and fixes the movement of an object in the detection zone. Due to their low cost and ease of use, such devices are used in systems burglar alarm, as well as to turn on various devices (lamps, etc.). To know how to choose a motion sensor, you need to understand their modifications and technical parameters.

Main varieties

There are several types of sensors that respond to the movement of an object. They work on different technical principles, but perform the same task. When detecting a moving object, it turns on a relay, to the contacts of which any external device can be connected.

Exist following types motion detectors:

• Infrared sensor;
• Ultrasonic sensor;
• Radio wave sensor.

The infrared sensor uses a PIR sensor that responds to the thermal radiation of an object. Sensors of this type are characterized by low cost, reliability and are used both in security systems, and to control lighting and other household appliances.

Ultrasonic sensors emit a signal at a frequency above 30 kHz and work as an acoustic locator. Sensors operating on this principle have a limited range due to signal attenuation, and their operation also disturbs pets. Among other things, they cannot be used outdoors due to large number moving objects.

Radio wave sensors also work like a locator, but instead of sound waves they emit microwave microwaves. Microwave radiation is unsafe for humans and the cost of radio wave sensors is slightly higher than that of other systems.

For use at particularly important objects, combined sensors are used, including an infrared detector and a radio wave sensor, located in a common housing and operating in parallel.

In and for control electrical appliances, the most widely used infrared sensors. They have a wide capture area, good range and are absolutely safe for humans.

There are innovative promising developments using semiconductor lasers, but so far such devices are expensive and have limited scope applications.

Motion sensor selection criteria

When choosing a motion sensor, the purpose for which it will be used is of great importance. Sensors used in lighting control systems and other household appliances have some Extra options, which are not available for devices for burglar alarms.

A motion detector for security is selected based on the following main characteristics:

• Sensitivity;
• Detection zone angle;
• Horizontal zone length;
• Fixed movement speed;
• The presence of an anti-sabotage zone;
• Supply voltage;
• Temperature range.

The sensitivity of a good motion sensor must necessarily be adjusted so that it does not react to pets. Some types of sensors are step adjustable, and some models are equipped with a trimming resistor, with which you can fine-tune the sensitivity. The angle of the detection zone is measured in degrees. Typically it varies from 90 to 120 degrees. The exception is motion detectors of the Shtora type, which create a narrow but horizontally extended zone. The length of the detection zone of conventional sensors can be 10-15 meters.

Sensors respond to object movement speeds as low as 0.1 meters per second, so very slow movement can deceive the sensor.

Anti-sabotage zone is a detection zone directed vertically downwards and prevents the possibility of damaging the sensor. To do this, most models have an additional lens in the lower part of the case.

The supply voltage usually does not exceed 12V, since it is this voltage that is generated by the power supply of the control panel. Infrared motion detectors are rarely used outdoors, so the operating temperature range is not important parameter. This does not apply to sensors designed to control lighting.

Sensors for lighting control

To know how to choose a motion sensor to turn on the light, you need to know some special parameters of such devices. Motion detectors for turning on lights or other equipment can be installed both indoors and outdoors, so you need to pay attention to the operating temperature range. must have a dust- and moisture-proof housing and an installation bracket that allows you to set desired zone triggering.

In addition to the viewing angle and the length of the detection zone, the sensors have the following parameters:

• Sensitivity;
• Light level;
• On time;
• Switching power.

Sensitivity determines the body weight to which the sensor will respond. This parameter is adjusted using a potentiometer on the sensor body. Just like in security sensors, the sensitivity is set in such a way that there are no false alarms on pets. The illumination level can also be adjusted. At the maximum position of the regulator, the sensor will operate at daytime, which is not required when turning on the lights, but may be important for turning on other devices.

If the sensor is designed to turn on the lighting, the illumination level is selected so that operation occurs only in the dark. By adjusting the on time you can set the interval during which the light will remain on. This time varies from a few seconds to several minutes. For user convenience, parallel to the motion sensor, it can be installed conventional switch. The switched power is indicated in the device passport and usually does not exceed 1.5-2.0 kW.

Model overview

Motion sensors for switching on electrical systems:

« SEN15/LX02"

"DD 010"

• Type – wall rotary sensor;
• Detection zone angle - 180°;
• Detection range – 10 meters;
• Mains voltage – 210-240 V;
• Switching power – 1100 W;
• Turn-on time – 5 seconds-6.5 minutes;
• Illumination level – 3-2000 lux;
• Installation height – 1.8-2.2 meters;
• Degree of protection – IP44;
• Temperature – from -20 to + 40 degrees;
• Price – 380 rubles.

Motion sensors for security alarms:

"Astra 5"

"Argus 3"

• Type – high sensitivity radio wave sensor;
• The area of ​​the detection zone is at least 20 m2;
• Adjustable range – 2-8 meters;
• Supply voltage – 10.5-15 V;
• Price – 870 rubles.

Sensors of this type can be installed in rooms where it is necessary to localize a small detection zone. This is achieved by adjusting the operating range.

To find your bearings on which outdoor sensor to choose, you need to carefully read the product data sheet. If the motion detector will be installed outdoors, then the lower and upper temperature limits should be selected depending on the climatic characteristics of the region. Besides, outdoor sensor must have a housing that protects against dust and moisture. To assess the degree of protection there is