The today's popular motion sensor was developed as a device for the protection of objects, allowing its suddenness to detect "unexpected guests". Now it's hard to imagine a "smart home" without it.
Is it necessary?
Not so long ago, finding a switch, especially in an unfamiliar room, was quite difficult. A little later, manufacturers began to equip switches with light indication. But this is at home. In the entrances and places of large concentrations of people, things were much worse. Especially in common areas without windows. The light in such places burns for days. In modern realities, in order to save electricity, lighting control devices are gaining more and more popularity. They turn on the light as needed and turn it off when the illuminated area is empty. This device is a light motion sensor.
Scope of application
Devices that react to movement and turn the light on and off, make it possible to enter an already lit room, find out what is happening in the yard (adjusting the motion sensor allows you to set it to anymovement) and at the same time significantly save on electricity bills. Most often, these smart devices are installed:
- on the stairs leading to the cellar or cellar, - above the front door to the entrance, - on the flight of stairs or in the hall, which do not have natural light, because they are located indoors,
- in the basement or cellar, - in toilets, bathrooms, showers, etc.
Modern motion sensors allow you to configure the inclusion (with or without it) of any household appliance. An air conditioner, for example, or a TV.
The optimal setting is considered if the motion sensor to the light is duplicated by a switch. Usually, the installation diagram, including this nuance, comes with the device.
Types and methods of installation
The principle of operation of the motion sensor to turn on the light allows you to separate them as follows.
- The sensor responds to ultrasound. That is, the device captures the movement by means of a reflected sound wave.
- The sensor uses high frequency waves for its operation.
- An infrared-based sensor detects any movement of warm-blooded creatures.
Setting the motion sensor to turn on the light may depend on the motion detection system. There are two;
- The device is active and emits a signal itself, and then reads the reflection from a possible object. The design of these devices usually consists of two elements: an emitter and a receiver. It is thisconstructive complexity increases the cost of the device;
- The device is passive. It is capable of registering only its own radiation, an object that has fallen into the device's coverage area. The design of the device is simple, so it is much cheaper. The downside, which is quite sensitive, is a high level of false positives.
Ultrasonic motion sensor
Most often it can be found in security systems in transport and parking lots. Benefits include:
- resistance to external influences and environmental factors, - readability of the reflected signal from any object, - medium price range.
It is realistic to assume that installing a motion sensor to turn on this type of light would be suitable for living spaces. But here you need to consider that:
- Animals can hear ultrasound very well.
- The device reacts to sudden movements, so objects that move slowly are not perceived by it.
- The range of the device is limited.
Microwave sensor
The motion sensor to the light of this type, like the previous one, is active. It differs only in waves. They are electromagnetic. The device emits them, then registers reflected from possible objects. If they move, then the frequency of the wave changes, which triggers the sensor. If they are static, then the wave returns unchanged.
This is the most commonly used device in security systems. Advantagessignificant:
- long range, - small dimensions, making the device almost invisible, - greater accuracy and reading of minor movements in the device's coverage area;
- detects movement behind the fence if it is made of non-conductive material.
In residential premises, a microwave motion sensor to light is used infrequently. Firstly, it is hypersensitive and often works for no reason, and secondly, it costs quite high compared to similar devices. Well, we must not forget that prolonged exposure to microwave rays has a negative effect on the human body.
Infrared sensor
As is known from the school physics course, any object has infrared radiation. The pyroelectric elements located in the registration sensor react to temperature changes and pick up the signal.
If there is a movement in the area of the sensor operation, which, of course, is accompanied by the emission of infrared waves, then the value of the output potential changes and the sensor is triggered. If there is no movement, as well as radiation, then the potential is constant and there is no reason for triggering either.
Infrared sensors are ideal for any premises, including residential ones. They do their job well and have undeniable advantages:
- the setting of this type of motion sensor has additional adjustments for the angle of the coverage area and the threshold, - the device is passive (no ownradiation), therefore does not have a negative impact on living organisms, - the device is in an affordable price category, - the sensor can be used outdoors and indoors.
The disadvantages are not so significant, but still there:
- temperature difference can lead to malfunction of the device, - heaters, radiating heat, can cause false alarms, - objects with non-conductive IR coating are not read by the sensor.
Motion sensor adjustment
Modern devices allow you to adjust the installation angle, turn-off delay time, illumination and sensitivity. Models of previous years of production have only a setting for the light level and delay time, or the latter and sensitivity.
It is possible to adjust the sensor coverage area only by adjusting the installation angle. Models of sensors produced today have hinges for this. They are fixed so that the infrared rays cover the maximum area for motion detection. The installation height of the device is of no small importance here: 2.40 m is considered optimal.
Setting the sensitivity is a bit tricky. The rotary lever (Sens) is intended for its adjustment. You need to configure it in such a way that the sensor "does not see" animals, but reacts only to humans. Experts recommend that you first set the lever to the maximum, wait until the light goes out and check how the sensor will work. Then you need to gradually reducesensitivity until the best match is found.
Setting the light means that the sensor will only be triggered at nightfall. You need to start, like the previous setting, by setting the maximum. With the advent of dusk, mark the triggering of the sensor and, at your discretion, increase or decrease the illumination.
The delay time is set last. It ranges from five to ten seconds and is adjusted according to personal feelings. There are models of sensors that increase the delay time with each subsequent activation.
As you can see, setting up the motion sensor is not particularly difficult.
Ceiling Motion Fixing Devices
This device is installed, due to its design features, only on a horizontal surface. The spherical body, with a viewing angle of 360o makes it possible to cover a large area. The ceiling motion sensor is considered a detection device. When a moving object appears in the zone of its action, the contact closes in the electrical network, which activates the light switching mechanism. The basic element of such a sensor is the Fresnel lens. When installing, you need to take into account that it cannot be blocked by any objects.
This ceiling-mounted unit has a 360 viewing angleo. If you install it at a height of no more than three meters, the diameter of the working area will be 10-20 m. That is, one sensor is enough for a small room. In large rooms, it is desirable to combine a ceiling motion sensor with a wall sensor.
Ceiling devices are overhead, wireless and built-in. The latter can be successfully hidden from prying eyes. Any of them are inexpensive and easy to install yourself.
Autonomous lamps with motion sensor
It is not the first year that you can buy a lamp with a battery-powered motion sensor in stores. Bribes almost everything in it. For example, there is no need to ditch the walls for laying wires, and there is no need to pay for all the rising electricity prices. And installation, a real pleasure: I removed the protective tape, stuck it to the surface and that's it!
The manufacturer supplied the models of such lamps with the most economical LEDs. The consumption is greatly reduced by the smart sensor. It is he who is responsible for the operation and turns the light on or off. Such devices are ideal in corridors without natural light, cellars, basements, storerooms, hallways and even cars.
A lamp with a motion sensor on batteries usually weighs no more than 100 g, has a width of just over a centimeter, and a height and length of 8 - 10 cm. It is installed on any surface. It can be attached with screws, glued with adhesive tape, placed on a cabinet shelf, or pressed down with a magnet.
Similar lamps are almost always equipped with an infrared motion sensor. Therefore, they need to be fixed away from sources of thermal energy. In some models, photocells activate the sensor only at night.
The timer turns off the device usually after 20-30 seconds, so 3A batteriesenough for quite a long time.
There are models of similar fixtures with controls for sensitivity, brightness, motion sensor for glow duration (30, 60, 90 seconds) and an off button.
When setting the motion sensor to turn on the light on batteries, you need to keep in mind that heat sources and animals cause the sensor to work. Therefore, in order to change batteries less often, it is advisable to set the sensitivity to a minimum.
Street lights with motion sensor
Modern lighting devices are used not only in the house. The adjoining territory of both a multi-storey building and a private one can no longer do without lighting devices in which a motion sensor for the street is built in. Today, such lamps are already considered as a design element. The principle of operation is the same for them, the devices differ in terms of energy carrier, scope and light element. The main technical and operational characteristics of the devices depend on the latter. Therefore, a street lamp with a motion sensor can have lamps:
- Classic. This includes both energy-saving lamps and incandescent lamps. Energy-saving light elements give a dim luminous flux, and incandescent lamps burn out quickly due to frequent mode changes.
- LED. Diodes are famous for their huge working resource, they do not emit heat, they shine brightly - all this with minimal energy consumption. This option is ideal for street lighting.
- Halogen. Intense luminous flux with extended service life and reduced energy consumption. But at the same time theyemit a lot of heat, so they are rarely used in flashlights.
In terms of energy, a street lamp with a motion sensor can be autonomous (powered by batteries), stationary (powered by mains) and non-volatile (powered by solar panels with batteries).
Motion sensor to turn on the light: connection
It is carried out using the terminal. Most often, three conclusions, sometimes four. There are four main connection schemes.
- Sequential.
- Parallel.
- Multiple devices.
- With magnetic starter.
Daisy connection means the motion sensor controls the lighting completely.
Parallel is necessary in case of prolonged illumination of the motion sensor area. After turning off the light with the switch, the sensor detects movement and turns it on again and turns it off according to the settings.
Several devices will be needed in large walk-through rooms. In this case, the sensors are connected in parallel from one phase. If one sensor is triggered, the others will also be activated.
Magnetic starter is mounted if motion sensors trigger powerful light elements or additional electrical appliances.
