How to Use KY-015 DHT11 Temperature-Humidity sensor module: Examples, Pinouts, and Specs

The KY-015 DHT11 is a sensor module designed to measure temperature and humidity. It provides a digital output, making it easy to interface with microcontrollers such as the Arduino UNO. This sensor is widely used in applications such as weather stations, environmental monitoring, and home automation systems due to its reliability and ease of use.

1. Connect the VCC Pin: Connect the VCC pin of the KY-015 DHT11 to the 5V pin on the Arduino UNO.
2. Connect the Data Pin: Connect the Data pin of the KY-015 DHT11 to a digital input pin on the Arduino UNO (e.g., pin 2).
3. Connect the GND Pin: Connect the GND pin of the KY-015 DHT11 to the GND pin on the Arduino UNO.

• Power Supply: Ensure the sensor is powered within the specified voltage range (3.3V to 5.5V).
• Signal Stability: Use a pull-up resistor (10kΩ) on the Data pin to ensure stable signal transmission.
• Response Time: Allow at least 1 second between readings to ensure accurate data.

#include <DHT.h>

#define DHTPIN 2     // Pin where the data pin of the DHT11 is connected
#define DHTTYPE DHT11   // Define the type of sensor used

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  dht.begin();
}

void loop() {
  delay(2000);  // Wait a few seconds between measurements

  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

  // Check if any reads failed and exit early (to try again).
  if (isnan(humidity) || isnan(temperature)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.print(" %\t");
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" *C");
}

1. No Data Output: Ensure all connections are secure and the sensor is powered correctly.
2. Incorrect Readings: Verify the sensor is not exposed to conditions outside its specified range.
3. Intermittent Data: Check the pull-up resistor on the Data pin and ensure it is correctly connected.

• Check Connections: Double-check all wiring and ensure there are no loose connections.
• Verify Code: Ensure the correct pin number is defined in the code and the DHT library is properly installed.
• Environmental Factors: Ensure the sensor is placed in an environment within its operating range for accurate readings.

By following this documentation, users can effectively integrate the KY-015 DHT11 Temperature-Humidity Sensor Module into their projects, ensuring accurate and reliable measurements.