PIR SENSOR HC-SR501 has Automatic induction: When someone enters its induction range, enter the high level, people leave the sensor range is automatically delayed off high. Output low.photosensitive control (optional): the module reserved for location, can be set to photosensitive control, strong light during the day or not induction. Photosensitive control is optional, the factory did not install photosensitive resistor. If necessary, please buy a separate photosensitive resistor to install.Two trigger modes: L is not repeatable, H is repeatable. Can be jumper selected, the default is H.

A. non-repeatable trigger mode: the induction output high, the delay time is over, the output will automatically change from high to low.

B. Repeated trigger mode: that is, after sensing the output high, in the delay time period, if the human body in its sensing range of activities, its output will remain high until the delay after the person will leave the high The level changes to low level (the sensing module automatically delays a delay time after every activity of the human body, and takes the time of the last activity as the starting point of the delay time).Induction blocking time (default setting: 3-4 seconds): After each sensing output (high level goes low), the sensing module can be followed by a blocking time, during which it is sensed The device does not receive any sense signals. This function can be used to achieve the interval between the sensing output time and the blocking time. It can be applied to the interval detection products. At the same time, this function can effectively suppress all kinds of interference in the process of load switching.

5. Wide operating voltage range: the default operating voltage DC5V to 20V

6. Micro-power: Quiescent current 65 microamps, especially for dry battery-powered electrical products.

7. Output high-level signal: can be easily with various types of circuits to achieve docking.