How to Use waterproof ultrasonic sensor: Examples, Pinouts, and Specs

The JSN-SR04T is a waterproof ultrasonic sensor designed to measure distances or detect objects using ultrasonic waves. It is specifically engineered to operate in wet or harsh environments, making it ideal for outdoor applications or areas exposed to moisture. The sensor emits ultrasonic sound waves and calculates the distance to an object by measuring the time it takes for the echo to return. Its waterproof design ensures reliable performance in challenging conditions.

• Water level monitoring in tanks or reservoirs
• Obstacle detection in robotics
• Parking assistance systems
• Outdoor distance measurement
• Industrial automation in wet environments

The JSN-SR04T is a robust and versatile sensor with the following key specifications:

The JSN-SR04T has a 4-pin interface for easy integration into circuits:

1. Power the Sensor: Connect the VCC pin to a 5V DC power source and the GND pin to ground.
2. Trigger the Sensor: Send a 10 µs HIGH pulse to the Trig pin to initiate a measurement.
3. Read the Echo: Measure the duration of the HIGH pulse on the Echo pin. The pulse width is proportional to the distance of the object.
4. Calculate Distance: Use the formula below to calculate the distance: [ \text{Distance (cm)} = \frac{\text{Pulse Duration (µs)} \times 0.034}{2} ] The factor 0.034 accounts for the speed of sound in air (340 m/s), and the division by 2 accounts for the round trip of the sound wave.

• Ensure the sensor is mounted securely to avoid inaccurate readings due to vibrations.
• Avoid placing the sensor near ultrasonic noise sources, as they may interfere with measurements.
• Use a pull-down resistor on the Echo pin if the signal is unstable.
• For outdoor applications, ensure the sensor is installed in a way that prevents water pooling around the connections.

Below is an example of how to use the JSN-SR04T with an Arduino UNO:

// Define pins for the JSN-SR04T sensor
const int trigPin = 9; // Trigger pin connected to digital pin 9
const int echoPin = 10; // Echo pin connected to digital pin 10

void setup() {
  // Initialize serial communication for debugging
  Serial.begin(9600);
  
  // Set pin modes for the sensor
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}

void loop() {
  // Send a 10 µs HIGH pulse to the Trig pin
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // Measure the duration of the HIGH pulse on the Echo pin
  long duration = pulseIn(echoPin, HIGH);

  // Calculate the distance in cm
  float distance = (duration * 0.034) / 2;

  // Print the distance to the Serial Monitor
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  // Wait before taking the next measurement
  delay(500);
}

1. No Output or Incorrect Readings

   • Cause: Incorrect wiring or loose connections.
   • Solution: Double-check all connections, ensuring VCC is connected to 5V and GND is properly grounded.

2. Unstable Distance Measurements

   • Cause: Electrical noise or interference.
   • Solution: Use a pull-down resistor on the Echo pin and ensure the sensor is not near ultrasonic noise sources.

3. Sensor Not Responding

   • Cause: Insufficient power supply.
   • Solution: Ensure the power supply provides a stable 5V DC and sufficient current (at least 30 mA).

4. Short Measuring Range

   • Cause: Obstructions or incorrect mounting.
   • Solution: Ensure the sensor has a clear line of sight and is mounted securely.

Q: Can the JSN-SR04T be used underwater?
A: No, the sensor is waterproof but not designed for underwater use. It is suitable for wet environments but must remain above water.

Q: What is the maximum range of the sensor?
A: The JSN-SR04T can measure distances up to 600 cm (6 meters) with an accuracy of ±1 cm.

Q: Can I use the JSN-SR04T with a 3.3V microcontroller?
A: The sensor requires a 5V power supply. If using a 3.3V microcontroller, a level shifter is recommended for the Trig and Echo pins.

Q: How do I protect the sensor in outdoor installations?
A: Ensure the sensor is mounted in a way that prevents water pooling around the connections and use a weatherproof enclosure for additional protection.