SeeedStudio Grove Gas Sensor (MQ9)

The HC-SR501 PIR Motion Detector Sensor Module is a pyroelectric device that detects motion by measuring changes in the infrared levels emitted by surrounding objects. This motion can be detected by checking for a high signal on a single I/O pin.

The module has an onboard pyroelectric sensor, conditioning circuitry, and a dome-shaped Fresnel lens. It has a delay time adjustment Potentiometer and sensitivity adjustment Potentiometer.

It is used to sense the movement of people, animals, or other objects. They are commonly used in burglar alarms and automatically-activated lighting systems. Compatible with ARDUINO, RASPBERRY PI, AVR, PIC, 8051, etc.

Features:

• Compact size
• Infrared sensor: dual-element, low noise, high sensitivity
• Blockade time: 2.5s (Default)
• Infrared Sensor with Control Circuit Board
• The Sensitivity and Holding Time Can be Adjusted
• Sensitive Setting: Turn to Right, Distance Increases (About 7M); Turn to Left, Distance Reduce (About 3M)
• Time Setting: Turn to Right, Time Increases (About 200S); Turn to Left, Time Reduce (About 5S).