PIR Motion Sensor, SR505, HC-SR505

The module is basically used in applications where you want to detect the motion of a body which emits infrared radiations. HC-SR505 is preferred to be used in battery operated systems since the device is specifically designed to be operated by consuming very less power. Because of its small size the module can be installed in applications where the system size is taken in to consideration.

How to use HC-SR505 Sensor

The device HC-SR505 can be installed in any system easily all you need to do is, connect the power to the module and receive the response from it. Let us consider simple application circuit of the device as an example.

In circuit

• The device is powered from a DC power source and it can range from +5V to +20V and in the circuit we are using +5V power source.
• The device response or output is connected to a LED to visualize the device response.
• The 1KΩ resistor is for limiting the current output from the device.

Working: For instance consider the module is powered and the lens of device is facing a solid wall. Under such case the sensor does not detect any IR (Infra Red) radiation change from the wall and it will provide LOW at the output pin. So when the device is faced solid walls and unmoving things the output will be LOW and the LED will be OFF.

Now if a human or a dog passes through its detecting area opposite to its lens, the module will detect the change in the IR radiation (as the living body emits IR radiation) and as a response provides HIGH logic at the output pin. So when the device detects a living body or IR emitting things the output will be HIGH and the LED will get turned ON.

This way we can use the device to detect motion of living things in front of its lens. We can connect the signal output to any microcontroller or arduino to do many fun things.

Applications

• Motion alarm
• Automatic lighting system
• Theft protection
• Staircase lighting system
• Hobby projects

2D-Model