Navig
home
one up
Div
NTC exercises

NTC exercises

For training purpose

No 1: get an NTC up and running

  1. Assume temperature 0-30C (living room)

  2. Select and get an NTC (10k/47K/…)

  3. Find Steinhart and Hart coefficients for the NTC

  4. Select computer (Arduino/ESP32/…)

  5. Select or decide power supply for voltage divider (typical 3.3V / 5V,…)

  6. Look at data sheet and select fixed resistor which is in middle for temperature range (0-30C)

  7. Do a mockup with breadboard

  8. Measure temperature with your device

  1. What is accuracy of measurement (what equals 1 bit)

    1. 10 bit ADC (UNO) or 12 bit on ESP (I assume)

    2. Measuring range 0-5V or 0-3.3V

  2. What is accuracy or resolution at 30C

  3. at 20 C

  4. at 10 C

  5. at 00 C

  6. Use Steinhart und Hart formula to calculate NTC values for temperature range form -10C to +40C

  7. Compare with your ADC resolution and argue for optimal fixed resistor values for

    1. 10C - 0C, 0C - 10C,l 10C - 20C, 20C - 30C, 30C - 40 C with one degree spacing

and

  1. Make a driver for your NTC resistor

    1. with C or cpp and h files to be located in sketchbook/libraries

NB

Formulas has a tendency to give Temperature in Kelvin …