# What is the resistance of NTC thermistor?

## What is the resistance of NTC thermistor?

NTC thermistors are usually characterised by their base resistance at room temperature, that is 25oC, (77oF) as this provides a convenient reference point.

### How many ohms should a thermistor be?

For example, if the specified resistance at 25°C for a thermistor with 10% tolerance is 10,000 ohms then the measured resistance at that temperature can range from 9,000 ohms to 11000 ohms….Thermistors/Temperature Measurement with NTC Thermistors.

511 512 513 0111111111 1000000000 1000000001 24.95°C 25.05°C 25.15°C

#### How do you calculate NTC thermistor resistance?

The actual resistance values of a particular NTC thermistor are obtained by multiplying the ratio RT/R25 (tabulated value) by the resistance value at 25 °C (specified in the data sheets).

How does the resistance of a NTC thermistor vary with temperature?

With an NTC thermistor, when the temperature increases, resistance decreases. Conversely, when temperature decreases, resistance increases.

Why does the resistance of an NTC thermistor decrease with temperature?

With NTC thermistors, resistance decreases as temperature rises; usually due to an increase in conduction electrons bumped up by thermal agitation from the valence band. An NTC is commonly used as a temperature sensor, or in series with a circuit as an inrush current limiter.

## How check NTC using multimeter?

Connect the multimeter terminals to the thermistor leads. Polarity is not an issue here. Now heat the thermistor by moving your heated soldering iron tip to it. Now you can see the multimeter reading smoothly increases or decreases depending on whether the thermistor under test is PTC or NTC.

### What does NTC mean in temperature sensors?

Negative Temperature Coefficient
When we are discussing NTCs we are referring to a type of temperature sensor; an NTC thermistor. In this instance, NTC defines as “Negative Temperature Coefficient”. Thermistors measure temperature by measuring the resistance of the electrical energy passing through the thermistor which is relative to temperature.