How to Use MKE-S05 NTC Temperature Sensor: Examples, Pinouts, and Specs

The MKE-S05 is a Negative Temperature Coefficient (NTC) thermistor used for precise temperature measurement. Its resistance decreases as the temperature increases, which makes it ideal for a wide range of applications including consumer electronics, automotive, and industrial systems where monitoring or controlling temperature is critical.

• HVAC systems (Heating, Ventilation, and Air Conditioning)
• Battery management systems
• Temperature monitoring in consumer electronics
• Over-temperature protection circuits

• Resistance at 25°C: 5kΩ
• B-value: Typically between 3000 and 4000 K
• Operating Temperature Range: -55°C to 125°C
• Thermal Time Constant: ≤ 7s (in still air)
• Dissipation Constant: 5mW/°C (in still air)

Note: The MKE-S05 NTC sensor is a two-terminal device, and the leads are non-polarized, meaning they can be connected in any orientation.

To use the MKE-S05 NTC temperature sensor in a circuit, it is typically connected in series with a fixed resistor to form a voltage divider. The voltage across the fixed resistor is then measured by an analog-to-digital converter (ADC) to determine the temperature.

Vcc ----[ R_fixed ]----|----[ NTC_Sensor ]---- GND
                        |
                       ADC

• Calibration: For accurate temperature readings, calibrate the sensor in the application environment.
• Thermal Coupling: Ensure good thermal contact between the sensor and the surface being measured.
• Avoid Self-Heating: Minimize current through the NTC to prevent self-heating which can skew readings.
• Protective Coating: If used in a harsh environment, consider a protective coating for the sensor.

• Inaccurate Temperature Readings: Check for proper calibration and ensure the sensor is not exposed to rapid temperature changes.
• Open Circuit: Ensure that there are no breaks in the circuit and that the sensor is properly connected.

• Calibration: Use a known temperature reference to calibrate the sensor.
• Stable Environment: Perform measurements in a stable temperature environment when possible.

• Q: Can the sensor be used to measure liquid temperatures?

  • A: Yes, but ensure the sensor is waterproofed or use a version specifically designed for immersion.

• Q: What is the typical response time of the sensor?

  • A: The thermal time constant is ≤ 7s, but the actual response will depend on the application and environment.

Below is an example of how to connect the MKE-S05 NTC temperature sensor to an Arduino UNO and read the temperature.

// Define the analog pin connected to the sensor
const int analogPin = A0;

// Define the value of the fixed resistor in the voltage divider
const float R_fixed = 10000.0; // 10k ohm resistor

// Define the nominal resistance and temperature
const float R_nominal = 5000.0; // 5k ohm at 25 degrees C
const float T_nominal = 25.0 + 273.15; // 25 degrees C in Kelvin

// Define the B-value of the thermistor
const float B_value = 3950.0; // B-value in Kelvin

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

void loop() {
  int analogValue = analogRead(analogPin);
  float voltage = (analogValue / 1023.0) * 5.0; // Convert to voltage
  float R_sensor = R_fixed * (5.0 / voltage - 1.0); // Calculate sensor resistance
  float temperatureK = B_value / log(R_sensor / R_nominal); // Calculate temperature in Kelvin
  float temperatureC = temperatureK - 273.15; // Convert to Celsius

  // Print the temperature to the Serial Monitor
  Serial.print("Temperature: ");
  Serial.print(temperatureC);
  Serial.println(" C");

  delay(1000); // Wait for 1 second before the next reading
}

Note: The code above assumes a 5V supply voltage for the Arduino. If using a different voltage, adjust the voltage calculation accordingly.

Remember to wrap the sensor in a waterproof material if it is to be used in a wet environment, and always ensure that the sensor is not subjected to voltages or currents that exceed its specifications.