Creating an automated washroom light using an IR (infrared) sensor is a fun and practical DIY project. Below are the steps and components needed to make one at home.

---

Components Required

1. IR Sensor Module (usually comes with a built-in IR emitter and receiver)
2. Relay Module (to control the high-power light)
3. Microcontroller (optional, like Arduino, for advanced features)
4. Light Bulb (any type, but ensure compatibility with the relay)
5. Power Supply (to power the sensor and relay)
6. Connecting Wires
7. Breadboard or Soldering Kit (for connections)
8. Resistors (as required by the sensor and relay)
9. Enclosure Box (to house the circuit for safety)

---

How It Works

The IR sensor detects motion or the presence of a person by sensing reflected IR light. When motion is detected:

• The IR sensor sends a signal to the relay.
• The relay, acting as a switch, turns the light ON.
• The light turns OFF after a set duration of no motion (based on sensor settings).

---

Steps to Make the Circuit

Step 1: Setup the IR Sensor

1. Connect the VCC and GND pins of the IR sensor to the power supply (e.g., 5V).
2. Connect the OUT pin of the IR sensor to the relay’s input (IN pin) or directly to a microcontroller input pin if used.

Step 2: Connect the Relay

1. Connect the VCC and GND of the relay module to the power supply.
2. Connect the IN pin of the relay module to the output pin of the IR sensor.
3. Wire the relay’s common (COM) and normally open (NO) pins to the light and mains supply:
   • COM: Connect to the live wire of the power source.
   • NO: Connect to the live terminal of the light.
   • Neutral goes directly to the light.

Step 3: Test the Circuit

1. Ensure all connections are secure.
2. Power the system. When the IR sensor detects motion, it should send a signal to the relay to turn the light ON.

Step 4: Adjust the IR Sensor

• Use the potentiometer on the IR sensor to adjust the sensitivity and delay time (if supported).

Step 5: Enclose the Circuit

• Place the circuit in an enclosure box to prevent exposure to moisture or physical damage.

---

Optional Features

1. Microcontroller (e.g., Arduino)
   • Add a microcontroller to fine-tune the light timing or integrate with a smart home system.
2. Daylight Sensor
   • Add a photoresistor to prevent the light from turning ON during the day.
3. Indicator LED
   • Include an LED to indicate when the sensor is active.

---

Safety Tips

1. Always disconnect the power supply while making connections.
2. Use insulated wires and proper enclosures to avoid electric shocks.
3. Ensure the light and relay are compatible with your mains voltage (e.g., 110V or 220V).

---