This security alarm circuit using RCWL-0516 microwave radar motion sensor will detect any moving thing in the restricted area and turn ON an alarm sound.
The RCWL-0516 is basically an advanced motion sensor using microwave radar signals.
I have already discussed the working of RCWL-0516 elaborately, which you can read for more details.
The following figure shows the full circuit diagram of the proposed security alarm circuit using RCWL-0516 microwave radar motion sensor.
Referring to the above figure, the working of the circuit can be learned from the following points:
The circuit operation is actually very straightforward, thanks to the outstanding RCWL-0516 motion sensor module.
As we know that the RCWL-0516 module will detect anything that moves within its detection range and in response produce a positive voltage at its OUT pin.
Therefore as soon as a potential intruder or burglar tries to trespass the restricted zone, it is quickly detected by the RCWL-0516 module.
This causes the RCWL-0516 "OUT" pin to generate a positive voltage which is sent to the base of the TIP122 transistor via the 4.7k resistor and the LED.
The LED lights up, and the TIP122 switches ON turning ON the alarm device.
The alarm starts sounding indicating a possible intrusion in the protected zone.
If you want the circuit to be functional only during nighttime or in darkness, you can add an LDR on the back side of the RCWL-0516 module.
Whenever an intruder is detected, the RCWL-0516 module keeps the siren activated as long as the intruder movement is detectable in the area. It shuts down the siren after a delay of 2 seconds once the moving object is terminated from the detection zone.
- Resistors are 1/4 watt 5% CFR
- 4.7k = 1
- 10k = 1
- Transistor TIP122 = 1
- RED LED 5mm, 20mA = 1
- Diode 1N4007 = 1
- 12V Siren Module = 1
- RCWL-0516 module = 1
- 12V 1 amp Power supply SMPS = 1