Ultrasonic Module Distance Measuring Sensor HC-SR04
Ultrasonic ranging module HC-SR04 provides 2cm - 400cm (0,7" - 157") non-contact measurement function, the ranging accuracy can reach to 3mm. The modules includes ultrasonic transmitters, receiver and control circuit.
How it work?
- Using IO trigger for at least 10us high level signal.
- The Module automatically sends eight 40 kHz and detect whether there is a pulse signal back.
- IF the signal back, through high level , time of high output IO duration is the time from sending ultrasonic to returning.
Test distance = (high level time × velocity of sound (340M/S) / 2
Instructions for use:
- The module is not suggested to connect directly to electric, if connected electric, the GND terminal should be connected the module first, otherwise, it will affect the normal work of the module.
- When tested objects, the range of area is not less than 0.5 square meters and the plane requests as smooth as possible, otherwise ,it will affect the results of measuring.
How to Set Up an Ultrasonic Range Finder on an Arduino