enow.com Web Search

  1. Ad

    related to: ir sensor vs pir alarm clock battery 0920 12 pack charger

Search results

  1. Results from the WOW.Com Content Network
  2. Passive infrared sensor - Wikipedia

    en.wikipedia.org/wiki/Passive_infrared_sensor

    A passive infrared sensor (PIR sensor) is an electronic sensor that measures infrared (IR) light radiating from objects in its field of view. They are most often used in PIR-based motion detectors . PIR sensors are commonly used in security alarms and automatic lighting applications.

  3. Motion detector - Wikipedia

    en.wikipedia.org/wiki/Motion_detector

    A passive infrared detector mounted on circuit board (right), along with photoresistive detector for visible light (left). This is the type most commonly encountered in household motion sensing devices and is designed to turn on a light only when motion is detected and when the surrounding environment is sufficiently dark.

  4. Infrared detector - Wikipedia

    en.wikipedia.org/wiki/Infrared_detector

    An infrared detector is a detector that reacts to infrared (IR) radiation. The two main types of detectors are thermal and photonic (photodetectors). The thermal effects of the incident IR radiation can be followed through many temperature dependent phenomena. [2] Bolometers and microbolometers are based on changes in resistance.

  5. List of battery sizes - Wikipedia

    en.wikipedia.org/wiki/List_of_battery_sizes

    This battery, introduced in 1901, was very common in continental Europe until the 1970s. It usually contains three B cells in series. In Switzerland as of 2008, 4.5-volt batteries account for only 1% of primary battery sales. [89] PP3, 9-volt, or E [90] Radio battery Smoke alarm battery Square battery Transistor battery 006P MN1604

  6. Electro-optical sensor - Wikipedia

    en.wikipedia.org/wiki/Electro-optical_sensor

    An optical sensor converts light rays into electronic signals. It measures the physical quantity of light and then translates it into a form readable by an instrument. An optical sensor is generally part of a larger system that integrates a source of light, a measuring device, and the optical sensor. This is often connected to an electrical ...

  7. Alarm clock - Wikipedia

    en.wikipedia.org/wiki/Alarm_clock

    This is an accepted version of this page This is the latest accepted revision, reviewed on 23 January 2025. Type of clock A traditional wind-up (key-wound), mechanical spring-powered alarm clock An alarm clock or alarm is a clock that is designed to alert an individual or group of people at a specified time. The primary function of these clocks is to awaken people from their night's sleep or ...

  8. Security alarm - Wikipedia

    en.wikipedia.org/wiki/Security_alarm

    Sensors: In a security alarm, some sensors detect intrusions. Sensors' locations are at the perimeter of the protected area, within it, or both. Sensors can detect intruders by different methods. Alerting devices indicate an alarm condition. Most commonly, these are bells, sirens, also and or flashing lights. Alerting devices serve the dual ...

  9. Occupancy sensor - Wikipedia

    en.wikipedia.org/wiki/Occupancy_sensor

    Occupancy sensor types include: PIR sensors, which work on heat difference detection, measuring infrared radiation.Inside the device is a pyroelectric sensor which can detect the sudden presence of objects (such as humans) who radiate a temperature different from the temperature of the background, such as the room temperature of a wall.

  1. Ad

    related to: ir sensor vs pir alarm clock battery 0920 12 pack charger