Motion sensors- small helpers, great savings
In order to significantly reduce the consumed electrical energy, you can resort to installation of LED motion sensors, (or, as they are also called, “passive infrared sensors”) in rooms, apartments, offices or streets. To date, due to the environmental situation, and also with the purpose of saving resources for future generations, the most urgent problem is the use of technologies aimed at energy saving in everyday life. By the way, the economic factor is also important here: the price for electricity grows disproportionately to the financial possibilities of the population.
Principle of work
Motion sensors, using LEDs, are designed to close the power circuit when motion occurs, whether it is a person or a car, in the sensor control area. The device can be used both outdoors and indoors, depending on its performance.
The household motion sensor works on the principle of “constant monitoring of infrared radiation”, carried out in a certain tracking zone. When in its field of “sight” an object with sufficient mass and temperature that exceeds by 5 degrees Celsius ambient temperature falls, the thermal field in the control zone changes. A special lens, called the Fresnel lens, sends a signal to the photocell which allows the mechanism closing the electrical circuit to operate.
Active and passive zones in the infrared field alternate in staggered order, which makes it possible to operate the device even when the movement in the controlled zone is insignificant. This system is easy to use when switching on / off lighting, ventilation systems, and air conditioners. The response periods are regulated and depend on the model of the device and its purpose.
Before you buy motion sensors, be sure to determine by several parameters:
- The field of use: indoors, under a canopy, on the street. This parameters influence on the location, the degree of protection of LED sensors, and the method of installation. The sensors can be waterproof and dustproof, recessed, hinged.
- The power of the electrical switched equipment: the sensors can be installed in a room with one or several lamps, with complete set of ventilation, cooling equipment (warehouses, refrigerators, industrial hot spots). There are models that allow including lamps of 200 watts and even of tens kilowatts. It all depends on the size of the sensors and installation conditions.
- The possibility of the most accurate time setting for triggering (on / off). This function is very important when it goes about large rooms, for example, industrial, when a large area must be completely covered by the action of the sensor. So, in a long corridor, in a large warehouse, a person must have time to walk from one sensor to another and not to remain in the dark for a second, or to perform a certain job without leaving the area of operation of the device.
- The configuration of the triggered zone. Here it is important to remember that only the visible to the sensor area gets to its control zone. Glass is an obstacle to infrared radiation; it can reduce the control zone. Any structural features of the room (cornices, hanging lamps) can significantly reduce the radius of the sensor.
- The angle of perception. Devices are produced with a viewing angle of 180-360 degrees. The device with an overview of 180 degrees normally mounted on the wall, with an angle of 360 is to be placed under the ceiling.