The NTC 10K Waterproof Probe Analog Temperature Sensor is a versatile device that measures temperature by gauging the resistance of a thermistor. It features a 0.5m cable with a 2-pin connector, allowing for flexible installation. With a temperature range from -20°C to 105°C and an accuracy of ±0.5°C, it provides precise temperature data. Operating at 5V, it's compatible with popular platforms like Arduino and ESP32, making it suitable for various applications, including thermostat solutions. Whether you're a hobbyist or an engineer, this sensor is a valuable tool for temperature-sensitive projects.

 

Package Includes:

• 1x NTC Temperature Analog Sensor NTC 10K Waterproof Probe
  
  

Features:

• Thermistor-Based Temperature Measurement: This sensor relies on the resistance of a thermistor to accurately measure temperature, ensuring reliable data collection.
• Flexible Cable with 2-Pin Connector: The module includes a 0.5m cable with a 2-pin connector, offering flexibility in installation. Users can easily customize the cable to suit specific project requirements.
• Wide Temperature Measurement Range: With an impressive temperature measurement range spanning from -20°C to 105°C, this sensor is versatile and suitable for monitoring temperature across a broad spectrum of environments.
• Exceptional Measurement Accuracy: It boasts a high measurement accuracy of ±0.5°C, ensuring precision in temperature readings, making it ideal for applications where accuracy is crucial.
• 5V Operating Voltage: The sensor operates efficiently at a standard voltage of 5V, making it compatible with a wide range of popular electronic hardware platforms, including but not limited to Arduino and ESP32.
• Versatile Compatibility: Its compatibility with commonly used electronic platforms simplifies integration into various projects, making it accessible to both beginners and experienced engineers.
• Applications in Thermostat Solutions: The sensor is well-suited for thermostat solutions, making it a valuable component in temperature control systems. It can enhance the efficiency and accuracy of temperature regulation.

 

Description:

The NTC 10K Waterproof Probe Analog Temperature Sensor stands as a cornerstone of precision in temperature measurement. This sensor is ingeniously engineered to harness the resistance characteristics of a thermistor, and it comes with a versatile 0.5m cable featuring a user-friendly 2-pin connector. Notably, this connector can be effortlessly trimmed, allowing users to tailor the cable length to their exact requirements. This sensor boasts a remarkable measurement accuracy of ±0.5°C, making it a dependable choice for applications demanding pinpoint temperature control and monitoring. Whether it's maintaining the optimal climate for scientific experiments or ensuring the safe operation of industrial equipment, this sensor's precision is unmatched. With a temperature measurement range spanning from a chilly -20°C to a scorching 105°C, this sensor is ready to tackle a wide array of environments. From deep freezer units to industrial ovens, it excels in delivering accurate readings across diverse temperature ranges. The sensor operates effortlessly on a 5V voltage, making it harmonious with popular electronic hardware platforms such as Arduino and ESP32. Its compatibility facilitates streamlined integration, enabling both beginners and seasoned engineers to leverage its capabilities seamlessly. 

 

Principle of Work:

The NTC 10K Waterproof Probe Analog Temperature Sensor operates based on the principles of a Negative Temperature Coefficient (NTC) thermistor. Here's how it works internally:

1. Thermistor Element: At its core, the sensor contains an NTC thermistor, which is a type of resistor whose resistance decreases as the temperature increases. This thermistor element is made from special materials with these characteristics.
2. Voltage Divider Circuit: To measure temperature, the sensor incorporates a voltage divider circuit. This circuit consists of the NTC thermistor and a fixed resistor. As the temperature changes, the resistance of the NTC thermistor changes, altering the voltage division in the circuit.
3. Analog Output: The varying voltage at the output of the voltage divider circuit corresponds to the changing resistance of the thermistor, which, in turn, reflects the temperature. This analog voltage output is proportional to the temperature being measured.

Interaction with MCU (Microcontroller Unit):

To utilize the NTC 10K Waterproof Probe Analog Temperature Sensor with a microcontroller unit (MCU), such as an Arduino or ESP32, you can follow these steps:

1. Connection: Connect the sensor to the MCU. Typically, the sensor has three wires: power (VCC), ground (GND), and signal (analog output). Connect VCC to the MCU's 5V power source, GND to the MCU's ground, and the signal wire to one of the analog input pins.
2. Code Implementation: Write a simple code in the programming language suitable for your MCU (e.g., Arduino's C/C++ or ESP32's Arduino IDE) to read the analog voltage from the sensor's signal pin. Most MCUs provide functions or libraries for analog-to-digital conversion (ADC), which you can use to translate the analog voltage into a digital temperature value.
3. Conversion: Use the analog-to-digital conversion function to convert the sensor's analog voltage reading into a temperature value. The code will typically involve mapping the voltage to a temperature range based on the sensor's characteristics and the thermistor's resistance-temperature curve.

4. Types of Thermistors: It's worth noting that thermistors come in two main types based on their resistance variation with temperature:

   • PTC (Positive Temperature Coefficient): In PTC thermistors, resistance is directly proportional to temperature, decreasing as temperature decreases and vice versa.
   • NTC (Negative Temperature Coefficient): In NTC thermistors, like the one used here, resistance is inversely proportional to temperature, decreasing as temperature increases and vice versa.
5. NTC Thermistor in Use: The NTC thermistor employed in this sensor has a resistance denoted as 103, indicating its resistance at normal temperature, which is 10k Ohm.
6. Resistance Measurement: To measure the resistance of the NTC Thermistor, the voltage from the voltage divider (output) is measured. The voltage divider equation, Vout = Vin*[R2/(R1+R2)], is employed. With known values of Vin, R1, and Vout, the resistance of the NTC thermistor (R2) can be calculated using the equation R2=(Vout*R1) / (Vin-Vout).

 

Pinout of the Board:

The cable can be directly plugged into compatible thermostat solutions. Alternatively, you have the flexibility to cut the connector and utilize it as a standard NTC sensor, providing you with adaptability for various applications. Integrating the NTC Cable into your circuit is straightforward. Utilizing the voltage divider method, you will require a 10k resistor. The pinout configuration for this connection is illustrated in the following diagram for your convenience.

NTC 10K Waterproof Probe	Description
Resistor side	VCC
Middle	Out
the other side of the NTC Cable	GND

 

Applications:

1. Temperature Monitoring in Home Automation: It can be used in home automation systems to control heating and cooling systems, ensuring comfort and energy efficiency. It enables homeowners to create smart temperature control solutions.
2. Weather Stations: The sensor is suitable for weather stations, both personal and professional. It provides accurate temperature data for weather analysis and forecasting.
3. Industrial Temperature Control: In industrial settings, it's used to monitor and control temperature in manufacturing processes, ensuring product quality and safety. It's commonly found in ovens, furnaces, and industrial refrigeration units.
4. Environmental Monitoring: This sensor is ideal for environmental monitoring systems, such as those used in agriculture or ecology research. It can measure temperature variations in soil, air, or water, helping researchers make informed decisions.
5. Equipment Protection: It's used in equipment control and protection circuits to prevent overheating and damage. For example, it can safeguard motors, transformers, and power supplies.
6. HVAC (Heating, Ventilation, and Air Conditioning) Systems: The sensor can be integrated into HVAC systems to maintain the desired room temperature, ensuring comfort and energy efficiency.
7. Medical Devices: In medical equipment like incubators or thermal therapy devices, this sensor helps in precise temperature control, critical for patient well-being.
8. Food Processing and Storage: It's used in food processing industries to maintain the correct temperature during various stages of production and storage, preventing spoilage and ensuring food safety.
9. Cold Chain Management: The sensor plays a crucial role in monitoring and maintaining temperature during the transport and storage of perishable goods, like pharmaceuticals and food products.

 

Circuit:

Connection	Component	Arduino Pin
Middle of NTC to A0	NTC Temperature Sensor	A0
The other side of NTC	NTC Temperature Sensor	GND
Resistor side	10k Resistor	5V

Library: 

you don't need any library to work with this sensor.

 

Code:

this code reads analog voltage values from a thermistor connected to an Arduino, calculates the thermistor's resistance, and then uses the Steinhart-Hart equation to convert the resistance into temperature readings in Celsius. These temperature readings are printed to the serial monitor for monitoring and debugging:

#define ntc_pin A0                 // Pin to which the voltage divider is connected
#define vd_power_pin 2             // 5V for the voltage divider
#define Rref 10000                 // Value of resistor used for the voltage divider
#define samplingrate 5             // Number of samples
#define beta 3950                  // The beta coefficient of the thermistor
#define nominal_resistance 10000   // Nominal resistance at 25⁰C
#define nominal_temperature 25.0   // Temperature for nominal resistance (usually 25⁰C)

int samples = 0;  // Variable to store the sample sum

void setup() {
  pinMode(vd_power_pin, OUTPUT);
  Serial.begin(9600);  // Initialize serial communication at a baud rate of 9600
}

void loop() {
  float average = 0;

  // Take voltage readings from the voltage divider
  digitalWrite(vd_power_pin, HIGH);
  for (int i = 0; i < samplingrate; i++) {
    samples += analogRead(ntc_pin);
    delay(10);
  }
  digitalWrite(vd_power_pin, LOW);

  average = samples / (float)samplingrate;
  Serial.println("\n");
  Serial.print("ADC readings: ");
  Serial.println(average);

  // Calculate NTC resistance
  float resistance = Rref / ((1023 / average) - 1);
  Serial.print("Thermistor resistance: ");
  Serial.println(resistance);

  // Calculate temperature using the Steinhart-Hart equation
  float temperature = 1.0 / ((log(resistance / nominal_resistance) / beta) +
                               (1.0 / (nominal_temperature + 273.15)));
  temperature -= 273.15;  // Convert to Celsius

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");

  samples = 0;  // Reset sample sum
  delay(2000);
}

1. Initialization: It starts by defining various constants and variables needed for the temperature measurement.

   • ntc_pin: Specifies the analog pin connected to the voltage divider with the thermistor.
   • vd_power_pin: Specifies the digital pin used to provide power (5V) to the voltage divider circuit.
   • Rref: Represents the value of the reference resistor used in the voltage divider.
   • samplingrate: Defines the number of analog samples to be taken and averaged.
   • beta: Specifies the beta coefficient of the thermistor, which is used in the Steinhart-Hart equation for temperature calculation.
   • nominal_resistance: Represents the nominal resistance of the thermistor at a standard temperature (usually 25⁰C).
   • nominal_temperature: Specifies the temperature corresponding to the nominal resistance (usually 25⁰C).
   • samples: A variable used to store the sum of analog readings.

2. Setup: In the setup function, it configures the vd_power_pin as an OUTPUT and initializes serial communication for debugging purposes with a baud rate of 9600.

3. Loop: The loop function is where the main temperature measurement process takes place. It follows these steps:

   • It initializes a float variable named average to zero, which will be used to store the average analog reading.
   • It takes a series of analog readings from the voltage divider circuit by repeatedly using a for loop. The voltage divider is powered (HIGH) before taking readings and powered off (LOW) after readings to save power.
   • These readings are summed up in the samples variable and averaged by dividing by the samplingrate.
   • The average reading is printed to the serial monitor.
   • It calculates the thermistor's resistance using the formula (Rref / ((1023 / average) - 1)).
   • Using the Steinhart-Hart equation, it calculates the temperature in Celsius based on the resistance, beta coefficient, and nominal values.
   • The temperature is printed to the serial monitor in Celsius.
   • The samples variable is reset to zero.
   • There's a delay of 2 seconds before the loop starts again.

Technical Details:

• Line length: 0.5M
• Probe size: 5x25mm
• Output: 2 lines
• Type: NTC 10k±1%3950
• Measuring range: -20 to 105 ° C
• B constant: 3380 k - / + 1%
• Typical constant dissipation 5 MW / °C
• Insulated probe: > 100 MOhm
• Maintain pressure: 9.8N (1kgF) for 1 minute without deformation
• Peak hold voltage-time: 2 seconds, AC1800V 1mA 2 seconds

 

Resources:

• Datasheet
• Tutorial
•  

Comparisons:
Comparing the NTC 10K Waterproof Probe Analog Temperature Sensor module to the LM35 temperature sensor depends on your specific application requirements. The NTC thermistor offers a broader temperature range and is suitable for harsh environments but requires more complex calculations. On the other hand, the LM35 is simpler to use and provides high accuracy, making it suitable for many temperature measurement applications:

NTC 10K Waterproof Probe Analog Temperature Sensor:

Features:

• Type: Negative Temperature Coefficient (NTC) thermistor.
• Temperature Range: -20°C to 105°C.
• Measurement Accuracy: ±0.5°C.
• Operating Voltage: 5V.
• Waterproof Probe: Suitable for use in wet or harsh environments.
• Compatibility: Works with popular microcontrollers like Arduino and ESP32.
• Applications: Home automation, weather stations, industrial control, and more.
• Requires additional components for accurate temperature calculations, such as a reference resistor and beta coefficient.

Advantages:

• Wide temperature range: It can measure a broader range of temperatures compared to the LM35.
• Waterproof probe: Suitable for applications where moisture or environmental conditions are a concern.
• Compatibility: Works well with various microcontroller platforms.

Disadvantages:

• Requires additional calculations: You need to perform complex calculations using the Steinhart-Hart equation to convert resistance to temperature accurately.
• May need external components: Requires a reference resistor and beta coefficient for accurate temperature calculations.
• Less straightforward: Not as straightforward to use as the LM35; requires knowledge of thermistor properties.

LM35 Temperature Sensor:

Features:

• Type: Analog temperature sensor.
• Temperature Range: Typically -55°C to 150°C (depending on the specific variant).
• Measurement Accuracy: Better than ±0.5°C, often ±0.1°C.
• Operating Voltage: Typically 4V to 30V.
• Linear Output: Provides a linear voltage output directly proportional to temperature.
• Does not require external components for temperature conversion.

Advantages:

• Simplicity: Provides a linear voltage output directly proportional to temperature, making it easy to use.
• High accuracy: Offers better accuracy than the NTC thermistor.
• No complex calculations: Does not require additional calculations for temperature conversion.
• Wide voltage range: Can operate at a wide range of voltages.

Disadvantages:

• Limited temperature range: The LM35 may have a narrower temperature range compared to some NTC thermistors.
• Not waterproof: LM35 sensors are not typically designed for wet or harsh environments.
• Compatibility: While it can work with various microcontrollers, it may require additional components like amplifiers in some cases.