Light sensor for street lighting- a device with which a flashlight, lamp or any other source of lighting will turn on automatically at dusk. Its operating principle is to respond to light levels. The basis of such a device is a photoresistor, a semiconductor whose resistance varies depending on the level of illumination (the amount of light that falls on it).
One of the most common sizes of light sensor
The simplest option is to connect a flashlight that will automatically turn on when it gets too dark outside (in the evening or at night). If you add a motion sensor to it, you get automated lighting with an energy saving function. The second option is to install lighting in the entrance. But here the photo relay will need to be “taken” outside to a place where the shadow will not fall.
Why not replace such a photo relay with a regular timer or a system that will turn on the lighting “on an alarm clock”? Because the twilight period comes every month 30 minutes earlier or later. In April, for example, at 18:30, and in August - already at 21:30. So you would have to adjust the timer’s operation monthly (if not weekly) and set a different time to turn it on. There is no such drawback with light sensors - they react specifically to brightness, so they adjust automatically.
Operating principle of a light sensor for street lighting
The light sensor is based on - photoresistor. Exactly the same one is installed, for example, in modern smartphones - with its help, the gadget determines the brightness level of the lighting and adjusts the backlight intensity (saves battery power). In light sensors, a photoresistor is included in the automatic toggle switch circuit - it turns on or off when darkness falls. It can be used not only for street lighting, but also, for example, to turn on automatic watering(in the evening).
Modern photo relays that respond to light intensity, which are sold in construction stores, are also equipped with a rheostat - with its help you can adjust the sensitivity of the photoresistor. It is recommended to use such models, since in winter the lighting outside is less bright. Without adjusting the sensitivity, the sensor will also work during the day.
What types of photo relays are there?
There are two types of photo relays in stores:
- Classic photo relays. Simple design, minimum functionality. They are cheap, but many of them do not even provide for adjusting the reaction to the intensity of external lighting.
- Twilight relay. “Smart” sensors are sold under this name, where you can adjust the response level; the light indicator itself can be remote and connected through the relay itself. In twilight ones it is often possible to connect up to 5 additional indicators at once, and for each of them you can set individual trigger settings. They cost several times more than simple photo relays.
What degrees of protection do photo relays have?
Denoted as IP 44, IP67, IP 69. Pay attention to the last digit: the higher it is, the better protection from moisture (the first number is the degree of protection against the penetration of foreign objects). Accordingly, to install the sensor outdoors, preference should be given to those with a protection class 45 or higher. A lower class is only suitable for installation in places that are carefully protected from moisture.
Table 1. Degrees of protection.
| Protection class | For what occasions is it suitable? |
|---|---|
| IP45 | Protects against moisture ingress from any angle and penetration of objects with a diameter of 1 mm or larger |
| IP67 | Protection against dust penetration into the body, withstands short-term immersion in water to a depth of 1 meter |
| IP69 | Complete protection against dust penetration, constant exposure to water will not harm the device |
| IP33 | Protects against objects with a diameter of 2.5 mm or larger and prevents droplets from entering the housing |
You should also pay attention to the temperature range at which the sensor operates correctly. Most models working temperature – from -20 to +50 degrees Celsius. With more low temperatures it may not work correctly. This is due to the change in the resistance of the semiconductor photoresistor as the temperature decreases environment(will turn on even if it is very bright outside). In more modern sensors, to level out this shortcoming, there are switches of the “winter-summer” type - it includes an additional resistor in the circuit.
By lamp type
Simple photo relays with 3 The contacts are suitable for connecting only incandescent lamps. Energy-saving ones (LED, halogen, gas-discharge, fluorescent) are connected to these only through a special adapter (for LED - with conversion to direct current, for fluorescent or gas-discharge - with a starting relay that increases the “starting” current). Many modern energy-saving lamps have built-in control units - if there is one, they can be connected directly.
Note! Which lamps a particular light sensor works with is indicated by the manufacturer on the packaging itself. There is also a designation there permissible load per sensor (in Watts or Volt-Amps). What happens if you connect an incompatible lamp to the sensor? IN best case scenario– nothing will happen, the lighting will not turn on. In the worst case, the lamp or relay will simply burn out due to incompatible currents (exceeding the permissible load or voltage).
By voltage
The most common ones are on 12V And 220V. The first are designed to work with direct current (can be powered from a car or any other battery), the second - with alternating current (connected to a household electrical outlet or a gas generator). Relay on 12V may be necessary, for example, if a strip is used as street lighting. In other cases, as a rule, a sensor is used 220V.
By control method
According to the control method, sensors are:
- With forced shutdown. That is, once triggered, they continue to operate until the power is turned off or the relay is manually turned off.
- With automatic shutdown. In terms of devices, they are the same as with forced shutdown.
- With energy saving function. These are additionally equipped with a motion sensor or sound sensor. They turn on only when motion or outside noise is detected. Unlike others, they allow the lighting to operate in short sessions, which will save on electricity. These should be taken if all street lighting consumes more than 300 – 500 Watt*hour.
- Programmable.These are the same twilight relays with many settings and adjustments. Such sensors are often equipped with a display, several additional rheostats and toggle switches.
Power classification
Denoted in kilowatts (kW). In some sensors it is indicated in VA (volt-ampere). Converted by the formula: 1000 VA is 1 kW. Since a phase is supplied to the input of the sensor, all the current supplied to the lighting devices literally passes through it. Indicated in kWh. The most common sensors are limited to 1,2,3, and 5 kW. For household use are used in most cases with a limitation of up to 1 and 2 kW.
How to choose the right sensor for this parameter? Sum up the consumption of all lighting lamps that are planned to be connected to the light sensor. For “power reserve” it is recommended to leave approximately 30 – 40% from the original power. That is, if the sensor has a limit of 1 kW, then it is not recommended to load it more 600 – 700 W*h. Otherwise, it will last much less time due to constant overheating of the photoresistor and diode bridge.
Find out, and also read its description and varieties, in a special article on our portal.
Prices for light sensors
Light sensor
Where to place the light sensor
It is recommended to place the connected light sensor in the place where all day long(meaning, all daylight hours) fall Sun rays. If you place it where there is a shadow from nearby trees, the sensor may not work correctly, especially on cloudy days.
Video - Design of a twilight sensor and photocell
If the sensor does not have moisture protection, then it should only be placed in a sealed capsule, but transparent. A plastic bottle is perfect for this; you can use specialized outdoor boxes for electrical wiring - they provide mounting for brick or concrete wall. If the security class IP67 or higher, then there is no need to worry about moisture protection.
You should also adhere to the following tips:
- do not place near the sensor artificial sources light, away from lamps and lanterns;
- do not place at height less than 2 meters, otherwise, it may get hit by car headlights;
- in an accessible place (the sensor, or rather the sensor, must be regularly cleaned of dirt and snow for it to work correctly).
How to make a light sensor yourself
It is quite possible to make a light sensor for street lighting yourself; you only need basic skills in working with a soldering iron, as well as the ability to read electrical circuits. The simplest sensor consists of two transistors (type KT315B), a photoresistor, a variable resistor (it also acts as a rheostat to adjust the response level), as well as a relay (3-pin, 2-pin suitable for relays with manual switching). The only drawback of such a light sensor is the high probability of false alarms due to self-induction. This defect can be eliminated using a diode, which will “cut off” the resulting induction current.
Advice! Where can I find schematics for such devices? There are plenty of them on thematic amateur radio forums. As an example, we can cite the most common sensors for assembling them at home.
If things are not going well with reading diagrams in the best possible way, then you can purchase a ready-made board, but without a photoresistor, purchase it in China - on the same Aliexpress they offer a huge number of them at a price from 10 – 15 rubles and higher. All that remains is to add the necessary version of the photoresistor and solder 3 input conductors (you can use a wire or a terminal block - whichever is more convenient for you).
Also for the sensor you need to make protective housing, must be transparent to allow sunlight to pass through to the photoresistor. Again - suitable for this purpose plastic bottle or glass jar.
Such photo relay boards can be bought on Aliexpress. average price— 25 rubles
Video - Do-it-yourself light sensor from components
Light sensor connection diagram - step-by-step instructions
Light sensors usually have only 3 contacts. They are designated by three colors: black, red, yellow (it can be changed to blue, brown, pink, white). It is necessary to apply phase to black, and zero to red. The third contact is the output contact, from which the phase is supplied to the lighting device (or junction box, from which street lighting is connected). An additional zero for lighting is taken directly from the shield; it can also be removed from any other electrical circuit Houses.
There are sensor models that have 4 and 5 wires. They allow you to connect several lines at once, that is, inside the phase is distributed over 2 or 3 output contacts. They are most often marked in the same way: the input to the phase and zero are black and red, respectively, the remaining contacts are in an additional color.
But the above marking principle is not followed by all manufacturers, so before installation you must read the attached instructions. In sensors where there are terminal blocks instead of input wires, there may be no markings at all.
In twilight relays the connection principle is similar, but most models also provide a zero output. That is, there is no need to connect it separately to the lighting - the wires come out directly from the relay. But this is also a disadvantage - the sensor itself is massive, and you have to allocate a separate junction box for it.
Attention! If you connect a powerful lamp (spotlights, incandescent lamps with power 250 Watt or more), then a magnetic starter is added to the circuit - it is precisely designed to pass through the starting current sensor. In many twilight relays it is preinstalled (indicated in the instructions).
After installation, all that remains is to adjust the operation of the sensor. In most models, a regulator for a Phillips screwdriver is provided for this. Operation adjustments should be made at the time of day when it is necessary to turn on the lighting.
Prices for cordless screwdrivers
Cordless screwdriver
In total, the algorithm for connecting the sensor will be as follows:
Step 1. Connect the power line to the sensor installation location. A phase and a zero will be required. It is not necessary to start from the panel if the total load does not exceed 0.5 - 1 kW.
Step 2. Disconnect the electrical wiring to connect the lighting (if there is only one photo relay, then the output from one line should be connected to the junction box). The phase is output from the connection point of the photo relay, the zero is input from the panel or other electrical wiring line.
Step 3. Connect the photo relay according to the diagram specified in the instructions (after de-energizing the line).
Step 4. Connect the output from the sensor to the lighting line (the output is a phase).
Step 5. Test connection of the line.
Step 6. Check the functionality of the sensor, if necessary, adjust the degree of response.
Review of popular models of street lighting sensors
As for manufacturers, the products of the following brands are in demand:
- Elko-EP;
- Euroelectric;
- Hager;
- Theben;
- PromAutomatika.
The best-selling models in many online stores are:
- Euroelectric 10A NEW. Plastic case, has a wall mount, suitable for connecting one line. Maximum current – 10A, working – up to 6A (1.3 kW). Among the settings - only the sensitivity regulator. One of the most simple models, but very reliable. Average price - 600 rubles.
- PromAutomation FRA 1-10. Universal relay, suitable not only for street lighting, but for turning on any electrical appliances. Maximum current – 10A, price - 400 rubles.
- Theben LUNA 122 top2.Twilight relay with DIN rail mounting. Professional model, a lot of settings (sensitivity, delay, connection of additional sensors, timer function, and so on). Can be used to control street lighting over large areas with connection to several separate lines. Average price - 17 thousand rubles.
- Eurolamp ST-303WSR. There is an adjustment of the response threshold, the maximum current strength is 25A. But it has low protection against moisture penetration, so it is installed only in dry places or in a protective housing. Average price - 350 rubles.
By the way, if you make a photo relay on one's own, then it will cost only 50 – 100 rubles– that’s exactly how much all the necessary components cost in radio stores.
Conclusion
In summary, from a design point of view, the light sensor is a fairly simple device. This is the same automatic switch, but it uses a photoresistor as an indicator that responds to the degree of ambient light. With him correct use(with the addition of an energy-saving mode and a motion sensor) you can save over over a year on constant street lighting 2 thousand rubles, so the device pays for itself fairly quickly.
Owners of their own homes often think about which light sensor to choose for street lighting. It’s very convenient when the light automatically turns on in the dark and turns off in the light. There are 2 options for this: install a photo relay or an astro-timer. Since the first device is more common due to its low price and availability, we will consider it first.
In this article:
Photo relay device
This device has different names. For example, photocell, light sensor, photosensor or photosensor, light sensor. However, the most common name is “photo relay”. With its help, you can automatically turn on the light in the dark and turn it off in the light.
It is based on photoresistors, photodiodes and phototransistors. When the light becomes weak and insufficient, they change the parameters. When certain values are reached, the contacts in the relay close and power supply to the lamps begins. Accordingly, as illumination increases, the parameters of the photosensitive elements begin to change again, but in the opposite direction, and the contacts open.
When choosing, you first need to decide on the voltage that will be in the network: 220 V or 12 V. Then select the protection class. IP44 can be considered the minimum. The higher the class, the better. This protection marking means that objects smaller than 1 mm in size will not fall into the lamp, and it is reliably protected from rain. It is also worth paying attention to temperature regime operation exceeded the maximum and minimum temperatures.
The output power of the light relay will depend on the total power of the connected lamps and current. To avoid overloads and breakdowns, it is better to take a device with a power reserve.
In some models, you can adjust the sensitivity of the photosensor. This is very convenient, for example, in winter when snow falls. The light sensor can perceive the reflected light as dawn and will turn the lamps on and off. It is worth paying attention to the presence of a response delay. By setting it for 5-7 seconds, you will prevent a power outage when light hits the sensor, for example, from car headlights.
Where to put the photo relay and how to connect it?
Motion sensors. Hurry up to buy at a discount!A correctly selected location for the device will ensure its correct functioning. The following must be taken into account:
- The sun's rays should fall on the photo relay, i.e. it must be located in the open air;
- Do not place artificial light sources near the sensor;
- place it at such a height that the headlights of passing cars do not fall on the photocell;
- the height should be convenient for maintenance (washing and removing snow).
To summarize, we can say that choosing a location is not the easiest thing. Sometimes you need to change it several times to find it best option. Sometimes LED spotlights are connected to the relay or Street light and hang the device on a pole. But this is an irrational decision, because... The box needs to be periodically wiped from dust; it is inconvenient to climb onto a pole each time to do this.
Connecting the light sensor is quite simple. 3 wires come out of the device: phase and zero to power the relay, switching phase to connect the lamp. The connection of the wires takes place in a junction box, which must be sealed, especially for the street. If you plan to connect only one lamp, the junction box can be installed next to the relay. Connection powerful backlight It's better to do it through the starter.
A motion sensor is used to turn on the light only when a person is present. In this case, the sensor is connected after the photo relay. It will only operate in the evening. The motion sensor can also be used to adjust the activation delay so that it is not triggered by the movement of a branch or a bird flying past.
A photo relay from any manufacturer has 3 wires for connection - 1 is always red, the other 2 can have different colors from different manufacturers (usually blue/dark green and black/brown). Red goes to lights or connects to a motion sensor. Connect blue or dark green to the neutral wire of the power cable and lamp, and connect the phase to black or brown. If the relay has custom colors wires, you should read in the instructions which wire should be connected where.
Light sensitivity is adjusted by rotating a small plastic dial on the bottom of the relay. There are always indicators next to it to indicate which direction to rotate it to increase or decrease the sensitivity of the photocell.
To adjust the light threshold, the following method is usually used: the regulator is set to the lowest sensitivity. In the evening, when backlighting is needed, the disk is smoothly tightened until the relay starts working. The setup is complete when the light comes on.
Despite the fact that the sensors are designed to turn on and off automatically, they have a special toggle switch or button that allows manual control device.
Astronomical timer
Motion sensors. Hurry up to buy at a discount!This device is inherently different from a photo relay. Automatic switching on of lighting occurs at a specified time. The astro timer is programmed with the times when it gets dark and light in different regions. And he makes adjustments using GPS. You just need to enter the coordinates of its location, the current date and time. Based on the entered data, he selects the appropriate program and works.
This device has a number of advantages over photo relays. The latter can work in cloudy weather or, on the contrary, go out in the middle of the night due to light falling on it. The astronomical timer does not have such a drawback. It can be installed anywhere outdoors or indoors. On it you can shift the lighting on and off by 2-4 hours. Its only drawback is the high price.
If you are choosing a device to illuminate streets or places where people stay for a short time (gate, toilet, etc.), a photo relay is suitable. But if you don’t want to depend on weather conditions and take care of the photocell, then it’s worth choosing the optimal astro-timer model for certain conditions and needs.
To simplify their lives and reduce electricity costs, owners often install in their homes different systems automatic control light. One of these electronic devices is a motion sensor switch (MS), which turns on the lighting without human intervention when a person enters the room.
And when there is no one in the room, this device itself turns off the light bulbs. Installing such a device is not difficult, and there are a lot of benefits from it. We will tell you how to choose the right smart device, in what order and where to attach it.
A circuit breaker with a non-contact motion sensor is a combined electrical appliance that responds to the movement of someone in certain area control. It is suitable for installation indoors and outdoors. You just need to wisely choose the degree of its IP protection.
This can be either a control unit with only a sensor, or a device supplemented with a key switch. However, in the first case, you won’t be able to turn on the lighting by hand by slamming a button on the wall. This feature of contactless automation should not be forgotten.
Ideally, the motion sensor is best complemented with a regular key switch; absolute automation of everything and anything in the event of failures in the electronics can cause a lot of trouble
The range of devices under consideration is huge. Electrical stores have options with different types detectors and different layouts. When choosing such a switch, the most important thing is to decide in advance where it will be installed.
In some cases, a combined model in one case is more suitable, while in others you will have to take several independent devices and connect them together with wires.
The light switch with a motion sensor works as follows:
- when there are no moving objects in the observation area, the device opens the power circuit;
- when a person enters the area, a sensor is triggered, which closes the power supply circuit of the light bulbs;
- as long as someone moves within the range of the sensor, the circuit remains closed;
- after everyone leaves the controlled room (or area on the street), the circuit opens again and the lights are turned off.
In order not to waste electricity during the day, such a switch is often supplemented with a photosensor for controlling the light level. In this case, as long as there is enough sunlight, the device will not operate and turn on the light bulbs.
If, in addition to a motion sensor, the selected switch is also equipped with a photo relay, then daytime the lighting will not turn on even when a person appears in the room
Switches with motion sensors are installed to control light in the following areas:
- on staircases and in the corridors of apartment buildings;
- in basements, storage rooms and garages, where there is no natural light at all, and the button regular switch difficult to find in the dark;
- in toilets and bathrooms to increase the comfort of using plumbing equipment when you are asleep at night;
- in private cottages built using smart home technology.
Often such a device is part security system. In this case, when the alarm is not functioning, the sensor works to turn the lights on/off, and when activated, it monitors the entry of strangers into the protected premises.
Types of motion sensors
To classify devices, we define two main factors: the presence and type of sensor device, as well as installation features.
The main element in the circuit breaker under consideration is a motion sensor. There are several varieties of it, based on different physical laws.
In all cases, the result is the same: when an object appears in the controlled area, the sensor is triggered and the contacts of the circuit supplying the lighting devices are closed.
The most common motion sensor is infrared - it does not emit anything, is relatively cheap and can be installed not only indoors, but also outdoors
Motion sensors for automatically turning on and off lights are:
- Acoustic.
- Infrared.
- Ultrasonic.
- Microwave.
The first two categories of sensors belong to passive devices; they do not emit anything. The detectors of the two remaining varieties are active devices. These options send waves of various lengths into the room, and by the nature of their reflection they determine the presence or absence of new objects in their coverage area.
Equipment of the “active” class with an emitter and receiver is more expensive than “passive” models. The devices are more complex in design, but have a low level of false alarms. Passive devices in this regard are much inferior to their active counterparts, but are cheaper than their competitors.
Acoustic sensors are triggered by the sounds of doors opening, the sound of heels, and simply sharp claps. This option is best taken for corridors of public buildings.
It is also ideal as an addition to other sensors, so that the light can be turned on by clapping your hands. It is not recommended to install it alone in a private house. There will be too many false reactions to various sharp sounds.
Infrared sensors are designed to be triggered by human heat. But they also react to animals and heated radiators. They must be carefully configured, and the coverage area must be set so that radiators do not fall into it. This is the simplest, most durable and cheapest touch sensor for automatic light control.
Operating principle of ultrasonic sensors. Ultrasonic and microwave sensors are similar in operating principle, they only have a different range of emitted waves
Sensors operating by emitting microwaves and ultrasound are not recommended for installation in residential premises. A person is not able to feel their impact, but it is there, but there is definitely no benefit from it. It has been noticed that domestic animals often react to this radiation in a sharply negative manner.
Such emitters are more suitable for parking lots or open areas. At the same time, active motion sensors also have a limited range.
When organizing control over a large area of ultrasonic devices, you will have to install a lot. Plus, many of them only work during sudden movements. A slowly walking person may completely “fall out” of their field of action.
The ideal option is a combined sensor with several methods of detecting people entering the controlled area. It is more reliable and less likely to trigger erroneously. However, you will have to pay a lot for this accuracy, since such sensors are obviously more expensive than conventional analogs.
Choosing the optimal installation location
If the key switch comes immediately with the sensor in the same housing, then it is designed for wall mounting. However, if the sensors are supplied in a disassembled kit or purchased separately, then they can be installed not only on the wall, but also on the ceiling. Moreover ceiling option often preferable because it covers a large area.
Each sensor device has its own viewing angle ranging from 10 to 360 degrees. If this parameter is less than 360°, then the sensor will be able to track movements only in a narrow observation sector. In this case, you will have to install several tracking devices in the room so that they cover all the required space.
Wide-angle and circular detectors are more expensive than those designed for a small coverage angle. However, too many of the latter may be required to completely control the room. Here it is important to carefully weigh and calculate everything before going to the store for consumables.
If the switch is placed in small room with one door, then with a narrow viewing sector it will be enough. You just need to point it precisely at the entrance and set the maximum possible time for turning on the light in the settings.
Another point is that the motion detector has a “dead zone” in height. During installation, you must carefully study the passport in order to correctly set the direction of operation of the sensor.
Plus there are still restrictions on the range of the detection zone. For verandas or long corridors It is recommended to choose long-range devices. However, remember that with a large area of control, they may begin to work too often at the wrong time.
Technical parameters and setup
Most models of light switches with a motion sensor are designed for direct connection of lighting devices to a 220 Volt network. In fact, this is a standard key-based light switch, but supplemented with a detector and an automation board.
Motion sensors can be powered directly from a 220 V power supply, batteries or via a 12 V power supply - the first option requires more wires, but is more reliable and preferable
Each model of the switch in question has a parameter indicated in its passport - the maximum connected power. It reflects the total power of connected lamps. If the device is used for a group of lanterns in a fence near a cottage, then this value should be around 1000 W.
Otherwise, it will burn out the first time you turn it on. For installation in the rooms of a private house or apartment, a device for 300–500 W is more than enough.
With the rules for connecting a motion sensor to the lighting device it serves, the contents of which are devoted to the analysis of this difficult issue.
The degree of protection must be at least IP44. This is quite enough for heated rooms in a cottage. But for installation outdoors or in a bathroom, it is better to take one with IP “55”, “56” or higher.
As a rule, a switch on the body equipped with a motion sensor has three adjustment controls:
- “TIME” – response time to turn off the light after a person leaves the room.
- “LUX” (“DAY_LIGHT”) – sensitivity to illumination (if there is a photo relay).
- “SENSE” – sensitivity to movement (temperature in the case of an infrared sensor).
The first parameter can vary from 0 to 10 minutes. If the narrow sensor is aimed only at the door in the pantry, then it is better to set this adjustment to maximum. Then, when entering the “dead zone,” you won’t have to worry that the light will turn off at the most inopportune time. At the same time, 5–10 minutes is quite enough to take something from a shelf in a closet.
The sensitivity to motion triggering and the degree of illumination are set by trial method. This is affected by the level of insolation, the presence of animals in the house and heating radiators nearby, and even swaying trees nearby. If there are too many false positives, then this parameter should be gradually reduced and brought to optimal values.
Basic installation diagrams
There are several schemes for connecting a switch and an external motion sensor to the power circuit of lighting devices. IN general outline: the sensor is inserted into the open phase wire. There are three terminals on its body. The corresponding cores of the power cable are connected to “L” and “N”, and from the third terminal the wire is sent to the lamp.
The simplest circuit with a motion sensor, but without key switch– the light will turn on only from the sensor built into the device
If one automatic detector is not enough and you need more manual method switching on the lighting, the “key” can be connected to the circuit in two ways. In the first, such a switch is inserted into the phase wire going to the sensor from the panel. When it is open, the sensor simply does not work and does not supply voltage to the light bulb.
The second option involves inserting a switch into the line from the phase to the input to the electric lamp. When such a “key” is closed, the light will remain on even if the sensor does not work.
Two schemes with different ways connecting a key switch to a circuit with a load (electrical lighting device) and a motion sensor
If you need to install several detectors, they are connected to each other in parallel. The power wire goes to the lamp from each of them. Light will appear when any of the sensors is triggered. If this solution seems unnecessarily complicated, it is better to purchase.
If the lighting device is powerful or there are several of them, then a magnetic starter with an amplifier should be installed in the circuit instead of a light bulb. And through it, power a separate lighting circuit. In this case, you can choose a low-power and cheaper detector.
Most quickly burn out when the voltage is turned on and off frequently. Therefore, connecting them via a motion sensor is not always advisable, since they will fail too often. The resulting savings from using such light bulbs will be zero.
To avoid problems with expensive lamps burning out, after the motion sensor, it is necessary to install a protection unit with soft switching on of the light in front of them. Due to the absence of sudden changes in voltage in the electrical network, light bulbs will not “burn” as often as without such a protective device.
You will be introduced to the markings and rules for selecting smart switches, which we strongly recommend reading.
Conclusions and useful video on the topic
To make it easier for you to understand all the features of choosing and installing the devices in question, we have made a selection of video materials for you. Everything is explained in detail and thoroughly.
Video #1. The nuances of connecting a motion sensor and a standard switch with a key:
Video #2. Overview of sensors for combined automatic lighting switches:
Video #3. Description of connection diagrams:
Automatic “switches” that incorporate a motion sensor are extremely easy to install. At the same time, energy savings from their use are significant. In addition, they make the house more comfortable to live in.
With the installation of such automatic devices There is no need to hesitate. You can do everything yourself, without the involvement of highly qualified electricians.
Please write comments in the block below, ask questions, post photos on the topic of the article. Tell us about how you chose a smart switch for your own home/apartment/office. Share useful information with site visitors.
Additional features in modern cars make driving more convenient and safer. One such option is a car light sensor. In the article we will talk about its structure and operating principle.
What is a light sensor in a car
Another name for this option is light sensor. Its device is quite simple. It consists of a photocell, a control unit and a small relay. The element itself is installed in the most illuminated place of the car, not subject to contamination. Usually above or below the windshield. Indirectly, a light sensor can be classified as a security system. The driver may simply forget or ignore the need to turn on the headlights when entering a tunnel or other darkened area. The system will do this itself.
Light sensor in the cabin
A photocell records changes in illumination in space. If there is not enough light, a signal is transmitted to the control unit, and then the relay turns on the low beam and side lights. If the system detects sufficient illumination, the lighting equipment turns off.
Light sensor device
The design of the component and the entire system is quite simple. If such an option is present in basic configuration car, it is located in a special recess in front of the windshield. The sensor housing contains an LED and photosensitive elements. The sensor is connected to the control unit, relay and contacts for turning on the headlights and low beam.
The lighting control switch must be set to AUTO for the system to operate in automatic mode.
Lighting system switch. AUTO position Special photodiode filters detect daylight and electric light. Very convenient, for example, when entering a tunnel or indoor parking. You can also adjust the dimming time of the headlights after turning off the ignition or in normal lighting.
Types of light sensors
Regular light sensor
If the car is not equipped with such a device, then you can easily install it yourself. The system is inexpensive. It is enough to fix the sensor, connect the relay and correctly connect the wires to the vehicle's electrical wiring. The system will work properly.
Built-in light sensor
Built-in light control components are included in more expensive car trim levels. As a rule, their range of functions is wider. You can configure the system to turn on the interior lights and turn on and off the instrument panel lights.
Combined light sensor
Often a light sensor can be combined in one device with a rain sensor. In this case, it is mounted at the top of the windshield. If everything is clear with the light sensor, then the operation of the rain sensor is also based on photodiodes and photocells. If raindrops fall on the windshield, the passing light is refracted differently and scattered on the way back. Photocells pick up this and... In heavy rain, the headlights also turn on automatically. Drivers note that the system works correctly and correctly. The driver does not need to turn on the windshield wipers every time the glass gets wet. The photocell detects the level of water on the glass and the intensity of rain and adjusts the frequency of the windshield wipers independently. In some models, when it rains, the glass is heated to prevent fogging.
How to check device functionality
This option is very convenient and drivers quickly get used to it. No need to worry about turning the headlights on or off - the system does it itself. But if the system fails, the car owner may not notice the breakdown in time.
Checking the light sensor is very simple. It is enough to cover it with dark material or rags. If everything is in order, the system will perceive it as night and turn on the lights and side lights.
I continue to talk about sensors in a car, and you know, today it’s not about the engine, but we’ll talk about the light (or light) sensor. Many people ask me questions - what is it, how does it work and is it possible to do it yourself. It should be noted that the thing is really “cool”, I would even say useful, as usual I’ll tell you everything in simple words, and at the end you can see short video. Well, let's begin...
Light sensor (light sensor) - this is a small photocell (with a small relay), with the help of which the car’s headlights are automatically turned on or off - as a rule, this is the front low beam. This element measures the light level and decides whether to turn the lamps on or off. The device is completely autonomous and very convenient, it knows exactly when it is necessary to turn on the light, for example - you drove into a valley underground crossing, you yourself may not guess about the light, but the sensor will react in a few seconds. This also happens at dusk; the drivers themselves, as a rule, are poorly oriented at this time of day, and the electronics never make mistakes.
Needless to say, cars are becoming more and more computerized, no one can be surprised by a box - a robot, automatic maintenance climate, automatic search for radio stations, etc. To be honest, soon cars will be able to drive themselves without a driver (GOOGLE) already has such developments, and I think this will happen in our lifetime. You just pressed a button on your smartphone, entered the coordinates, and she came for you, something like a taxi.
The light sensor is another step towards electronic control of the car, turning on the headlights for you!
Principle of operation
As I already wrote, this is a kind of sensitive photocell (with a relay), it is installed under or on the windshield of a car. This element measures the lighting next to it and makes a decision to turn the headlights on or off, which in turn either feeds directly into the shutdown system. At the threshold value, actions occur almost instantly - usually a delay of 2 - 3 seconds. That's why if you drive into a dark tunnel or underground garage, the sensor will work after about this time.
To put it in simple and understandable language, this is a kind of switch that works automatically and measures the level of illumination around it.
Usually the setting is carried out only for the low beam of the car headlights; you need to turn on the high beam yourself. Because it’s simply not safe, it can blind a car coming towards you.
How does it work
To be honest, there are only two settings:
1) This is a dark mode of the day. When the headlights only come on in the dark.
2) Twilight. When the lamps start working at dusk, when it is not so dark.
You can also configure the “on/off” of the headlights - for example, only low beam, low beam + fog lights. It's really convenient.
Typically, the operation of such sensors is implemented on a panel near the steering wheel. If there is a special mode “AUTO”, as well as normal modes for manual activation.
To activate, turn the knob to AUTO and that’s it, it will work according to the settings included in it.
I would like to note that in some cars, a delay system for turning off headlights is used. For example, you turned off the car in the garage, got out of it, closed the door, set the alarm - and the lighting still works! This was done specifically to illuminate your way, for example, you close the garage at night - so that you can see it. After 3 – 5 minutes the headlights will automatically turn off. Also a very convenient system.
For example, my friend doesn’t have lighting in his garage, and he often uses it in the fall - winter time when it gets dark early.
By the way, here is a short video about the one that is on my car.
What others are there?
It should be noted that light sensors are now used not only in low beam headlights, but also in the interior or, for example, in the side lights of trucks.
In the cabin - it can directly adjust the light level, light one or both interior lamps (front and rear). It’s also convenient if it’s light outside, then why burn the lamps in vain!
Special marker lights are used mainly for illuminating trucks. That is, during the day they do not work, even when the backlight is on - but as soon as it gets dark, the entire truck begins to glow. Made for safety!
Is it possible to install it yourself?
YES, of course you can - no problem at all. If you have a foreign car, in which the “poor” configuration does not have light sensors, then look at them in the “richer” ones. If they are present there, then you just need to buy them and install them yourself, or at least at a service station.
Often there is already a place in the instrument panel to mount it. Also, most likely you will need a different headlight switch; it will have an AUTO mode. Or you will just need to change the decorative backing under the handle. As a rule, the regime is also already laid down.
Therefore, the entire installation comes down to purchasing a sensor - if you need a handle - and connecting it to a special board. This information has already been discussed a hundred times on the forums about your model, I’m sure of it.
