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NTC Thermistor Temperature Calculator

Calculate temperature from NTC thermistor resistance using the Steinhart-Hart beta equation. Useful for PT100/PT1000 and generic NTC thermistors.

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Formula

1T=1T0+1βln(RR0)\frac{1}{T} = \frac{1}{T_0} + \frac{1}{\beta} \ln\left(\frac{R}{R_0}\right)
TTemperature (K)
T₀Reference temperature (K)
βBeta coefficient (K)
RMeasured resistance (Ω)
R₀Reference resistance at T₀ (Ω)

How It Works

NTC (Negative Temperature Coefficient) thermistors are temperature-sensitive resistors that change resistance predictably with temperature. The Steinhart-Hart equation provides a precise mathematical model for converting resistance measurements to actual temperature values. This advanced thermodynamic relationship allows precise temperature sensing across various applications in electronics, industrial monitoring, and scientific instrumentation.

Worked Example

Problem: Calculate the temperature for an NTC thermistor with R = 4500 Ω, R0 = 5000 Ω, β = 3950 K, at standard reference temperature T0 = 25°C Solution: 1. Apply Steinhart-Hart simplified equation: T = 1 / (1/T0 + (1/β) * ln(R/R0)) 2. Substitute values: 1 / (1/298.15 + (1/3950) * ln(4500/5000)) 3. Calculate intermediate steps 4. Result: Approximately 35°C (308.15 K)

Practical Tips

  • Always verify the specific β value for your thermistor model
  • Ensure stable measurement conditions for accurate readings
  • Use high-precision measurement equipment for best results

Common Mistakes

  • Confusing resistance values at different temperatures
  • Using incorrect β constant for specific thermistor type
  • Neglecting precise calibration of reference resistance R0

Frequently Asked Questions

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