Automation of stairwell lighting
One of the most important factors in the comfort of residents of apartment buildings is high-quality lighting at the entrance. At the same time, the costs of lighting the entrances account for a significant share of the general house expenses. Often, stairwells are illuminated by conventional incandescent bulbs that work, including during daylight hours, and the problem of energy overruns is solved by banal twisting of some of them.
This raises the question of the possibility of organizing the lighting of stairwells in another, more economical and technological way. This problem interested me because I encounter it every day and would like to find a way to solve it by the example of my entrance.
Purpose: to create a lighting automation device for stairwells of apartment buildings.
Tasks:
Object of study: Lighting staircases of apartment buildings.
Subject of research: Reasons for the irrational use of electric energy to illuminate the entrances of apartment buildings.
Any entrance of a residential building in accordance with the requirements of sanitary standards must be equipped with artificial lighting. (Clause 3.2.2 of SanPin 2.1.1 / 2.1.1.1278-03). As a rule, such lighting is organized using incandescent lamps controlled by a standard switch located on the wall. Incandescent lamps are a hopeless and uneconomical source of artificial lighting in comparison with modern fluorescent and LED lamps. The situation is exacerbated by ineffective lighting control, which is usually carried out by residents themselves. Lighting turns on on the landing with the onset of darkness and turns off (unfortunately, not always) with the onset of daylight. As a result, unreasonable energy consumption occurs.
A device for automating staircase lighting can be manufactured in various ways, both from the point of view of circuitry and from the point of view of the physical embodiment of the final product. Schematically, the device can be implemented both on discrete components, and with the use of digital integrated circuits, including microcontrollers, as well as ready-made modules.
The appearance of the finished device can be made in the form of a finished device that includes not only the automation device itself, but also a lighting device, being integrated with it. Another embodiment looks like a device mounted instead of a standard switch, or a device mounted in the immediate vicinity of a lighting device, on the ceiling.
In the market there are mainly models made in the form of a finished lamp, which replaces the standard lighting fixture. Which requires the dismantling of the latter and, accordingly, the installation of a new one. The samples on the market are equipped with a motion sensor (presence) in order to turn on the lighting only when a person is on the landing, as well as a photo sensor, so that the lighting turns on only in low light, which ensures energy savings when using such automation tools.
In this case, the motion sensor (presence) can be performed according to three main technologies:
The most promising from a technological point of view, I see a well-versed idea:
The appearance of the device should be selected in the form of a finished lamp, which includes an automation device and a lighting device. This choice is dictated by the fact that: the version of the device made in the form of a block mounted instead of a standard switch seems to me difficult to implement due to problems associated with the power of the device. The fact is that since the switch is installed in the open circuit of the power supply of the lighting device, only one pole of the supply network is suitable for it, which is not enough to organize the power supply of the device, and laying the second pole of the supply network to the switch is not always possible, and not technologically . The version of the finished device in the form of a unit mounted next to a standard lighting device, despite its lower cost, does not seem rational to me because of the complexity of its installation in the presence of hidden wiring.
I see the most rational technology for detecting the presence of a person as a microwave sensor based on the Doppler effect. For a number of reasons: the microwave sensor, unlike the infrared, does not impose requirements on the installation site and is capable of detecting movement through obstacles blocking it. Also, a microwave sensor does not require a person to do any additional manipulations (clapping), unlike an acoustic sensor. In addition, ready-made modules of microwave motion sensors combined with a light sensor are presented on the electronic components market, the cost of which, due to mass production in China, is low.
It follows from the foregoing that, from the point of view of circuitry, it is most rational to implement a device using a ready-made module of a microwave motion sensor combined with an ambient light sensor.
The final idea is to use the finished serial module of the microwave motion sensor based on the Doppler effect RCWL-0516:
The sensor is based on the Doppler effect - a change in the frequency of the reflected wave due to the movement of the reflecting surface. The module has the standard ability to connect a photoresistor to organize the module operation control depending on the light. The response threshold of the light sensor is set by selecting a resistor, the mounting location, which is provided on the module board. There is also a place on the module board for installing a capacitor responsible for determining the time period during which the lamp will be turned on after the motion sensor is triggered. Thus, the principle of operation of the finished device will be as follows: when motion is detected in the sensor coverage area,
Technical characteristics of the module:
The sensor has 5 pins:
In view of the fact that the module is powered by a low DC voltage, it will need a power supply. The simplest option for implementing a power supply, given that the module consumes a small amount of current, in this case will be the use of a transformerless power supply, as it is the simplest and has a small size and cost. Also, due to the fact that the device will control the high voltage load, you will need the appropriate actuator circuit. As the chosen one, the IRF740 powerful field-effect transistor, the choice was dictated by the correspondence of its electrical parameters to the required, as well as the low resistance of the open channel of the transistor, which will provide low power dissipated on the transistor and, accordingly, there is no need to use a radiator, which will positively affect the cost and overall dimensions devices.
Fig. 1
Diodes D1-D4 form a rectifier bridge, the pulsating voltage from which is supplied to the parametric stabilizer formed by the elements R1, D5, C1. The voltage of 12 volts filtered by capacitor C1 (the Zener diode D5 is designed for this voltage) is fed from the output of the stabilizer to the module's power inputs. Since the current consumption of the module is not large, insignificant power is released on the resistor R5. At the moment the sensor is triggered, a logical unit voltage appears at the module output, which is supplied to the gate of transistor Q1, which leads to its opening and switching of the load.
The load of the device is an LED lamp with a power of up to 10 watts.
In this circuit, it is powered by a pulsating current that is constant in direction, which, however, does not affect its performance in any way.
A ready-made plastic lamp designed for the use of modern LED lamps will be used as the housing of the finished device, the polymer material of the lamp housing will ensure the safety of the device, due to the use of a transformerless power supply in it.
The cost of the product does not exceed the cost of industrial products, but at the same time surpasses it in technical characteristics, which proves the feasibility of making this device with your own hands.
In the course of work on the project, I solved all the tasks set for myself to solve the problem of lighting the entrances of apartment buildings. I also happened to learn about the existing motion detection technologies, their differences, advantages and disadvantages. Learned to calculate a parametric stabilizer. I got acquainted with the principle of operation and the distinctive features of field-effect transistors with an induced channel.
This raises the question of the possibility of organizing the lighting of stairwells in another, more economical and technological way. This problem interested me because I encounter it every day and would like to find a way to solve it by the example of my entrance.
Purpose: to create a lighting automation device for stairwells of apartment buildings.
Tasks:
- To get acquainted with the main problems of the organization of lighting of the entrances of residential buildings.
- To get acquainted with the existing technologies for lighting the entrances of residential buildings, and choose the most economically viable device concept that meets the requirements of manufacturability.
- To design and manufacture an automation device for lighting stairwells that realize the goals of saving energy.
Object of study: Lighting staircases of apartment buildings.
Subject of research: Reasons for the irrational use of electric energy to illuminate the entrances of apartment buildings.
Problems of organization of lighting of entrances of residential buildings
Any entrance of a residential building in accordance with the requirements of sanitary standards must be equipped with artificial lighting. (Clause 3.2.2 of SanPin 2.1.1 / 2.1.1.1278-03). As a rule, such lighting is organized using incandescent lamps controlled by a standard switch located on the wall. Incandescent lamps are a hopeless and uneconomical source of artificial lighting in comparison with modern fluorescent and LED lamps. The situation is exacerbated by ineffective lighting control, which is usually carried out by residents themselves. Lighting turns on on the landing with the onset of darkness and turns off (unfortunately, not always) with the onset of daylight. As a result, unreasonable energy consumption occurs.
Search for the concept of the future device
A device for automating staircase lighting can be manufactured in various ways, both from the point of view of circuitry and from the point of view of the physical embodiment of the final product. Schematically, the device can be implemented both on discrete components, and with the use of digital integrated circuits, including microcontrollers, as well as ready-made modules.
The appearance of the finished device can be made in the form of a finished device that includes not only the automation device itself, but also a lighting device, being integrated with it. Another embodiment looks like a device mounted instead of a standard switch, or a device mounted in the immediate vicinity of a lighting device, on the ceiling.
In the market there are mainly models made in the form of a finished lamp, which replaces the standard lighting fixture. Which requires the dismantling of the latter and, accordingly, the installation of a new one. The samples on the market are equipped with a motion sensor (presence) in order to turn on the lighting only when a person is on the landing, as well as a photo sensor, so that the lighting turns on only in low light, which ensures energy savings when using such automation tools.
In this case, the motion sensor (presence) can be performed according to three main technologies:
- Infrared sensor with Fresnel lens.
- Acoustic sensor.
- Doppler microwave sensor.
The most promising from a technological point of view, I see a well-versed idea:
The appearance of the device should be selected in the form of a finished lamp, which includes an automation device and a lighting device. This choice is dictated by the fact that: the version of the device made in the form of a block mounted instead of a standard switch seems to me difficult to implement due to problems associated with the power of the device. The fact is that since the switch is installed in the open circuit of the power supply of the lighting device, only one pole of the supply network is suitable for it, which is not enough to organize the power supply of the device, and laying the second pole of the supply network to the switch is not always possible, and not technologically . The version of the finished device in the form of a unit mounted next to a standard lighting device, despite its lower cost, does not seem rational to me because of the complexity of its installation in the presence of hidden wiring.
I see the most rational technology for detecting the presence of a person as a microwave sensor based on the Doppler effect. For a number of reasons: the microwave sensor, unlike the infrared, does not impose requirements on the installation site and is capable of detecting movement through obstacles blocking it. Also, a microwave sensor does not require a person to do any additional manipulations (clapping), unlike an acoustic sensor. In addition, ready-made modules of microwave motion sensors combined with a light sensor are presented on the electronic components market, the cost of which, due to mass production in China, is low.
It follows from the foregoing that, from the point of view of circuitry, it is most rational to implement a device using a ready-made module of a microwave motion sensor combined with an ambient light sensor.
Ultimate idea
The final idea is to use the finished serial module of the microwave motion sensor based on the Doppler effect RCWL-0516:
The sensor is based on the Doppler effect - a change in the frequency of the reflected wave due to the movement of the reflecting surface. The module has the standard ability to connect a photoresistor to organize the module operation control depending on the light. The response threshold of the light sensor is set by selecting a resistor, the mounting location, which is provided on the module board. There is also a place on the module board for installing a capacitor responsible for determining the time period during which the lamp will be turned on after the motion sensor is triggered. Thus, the principle of operation of the finished device will be as follows: when motion is detected in the sensor coverage area,
Technical characteristics of the module:
- Supply voltage 4-28 v of a direct current
- Power Consumption: Up to 3 mA
- Detection Range: up to 9 m
- Transmit Power: Up to 30 mW
- Operating temperature range: -40- + 100 C
- Dimensions: 17.3 x 35.9 mm
- Weight: 4 gr.
The sensor has 5 pins:
- OUT sensor output (set to logic 1 if there is movement) maximum load 100 mA
- VIN input voltage supply + 4-28v
- GND power input (-)
- 3V3 stabilizer output 3.3v
- CDS work enable input
- CDS pins on the opposite side of the module for connecting a photoresistor.
In view of the fact that the module is powered by a low DC voltage, it will need a power supply. The simplest option for implementing a power supply, given that the module consumes a small amount of current, in this case will be the use of a transformerless power supply, as it is the simplest and has a small size and cost. Also, due to the fact that the device will control the high voltage load, you will need the appropriate actuator circuit. As the chosen one, the IRF740 powerful field-effect transistor, the choice was dictated by the correspondence of its electrical parameters to the required, as well as the low resistance of the open channel of the transistor, which will provide low power dissipated on the transistor and, accordingly, there is no need to use a radiator, which will positively affect the cost and overall dimensions devices.
Fig. 1
Diodes D1-D4 form a rectifier bridge, the pulsating voltage from which is supplied to the parametric stabilizer formed by the elements R1, D5, C1. The voltage of 12 volts filtered by capacitor C1 (the Zener diode D5 is designed for this voltage) is fed from the output of the stabilizer to the module's power inputs. Since the current consumption of the module is not large, insignificant power is released on the resistor R5. At the moment the sensor is triggered, a logical unit voltage appears at the module output, which is supplied to the gate of transistor Q1, which leads to its opening and switching of the load.
The load of the device is an LED lamp with a power of up to 10 watts.
In this circuit, it is powered by a pulsating current that is constant in direction, which, however, does not affect its performance in any way.
A ready-made plastic lamp designed for the use of modern LED lamps will be used as the housing of the finished device, the polymer material of the lamp housing will ensure the safety of the device, due to the use of a transformerless power supply in it.
The cost of the product does not exceed the cost of industrial products, but at the same time surpasses it in technical characteristics, which proves the feasibility of making this device with your own hands.
Introspection of work done
In the course of work on the project, I solved all the tasks set for myself to solve the problem of lighting the entrances of apartment buildings. I also happened to learn about the existing motion detection technologies, their differences, advantages and disadvantages. Learned to calculate a parametric stabilizer. I got acquainted with the principle of operation and the distinctive features of field-effect transistors with an induced channel.