How to Measure PTC and NTC Thermistors with Multimeter

PTC and NTC Thermistors with Multimeters – Thermistor (NTC/PTC) is a type of resistor whose resistance value can be affected by the temperature or temperature around it. To test or measure whether an NTC or PTC Thermistor can function properly or not, we can use a Digital Multimeter or Analog Multimeter with the help of heating devices such as soldering iron, hair dryer or other types of heaters. In addition to being able to measure or test the Thermistor, we can also distinguish the type of Thermistor that we measure / test whether it is a type of PTC Thermistor  (Positive Temperature Coefficient)  or the type of NTC Thermistor  (Negative Temperature Coefficient).

Read also How to measure The Potentiometer with Multimeter

Here is how to measure NTC and PTC Thermistors using multimeters:

How to Measure Thermistor PTC(Positive Temperature Coefficient)

1. Set the Multimeter Switch Position at ohm position (Ω)
2. Connect the Probe on the Thermistor’s Leg (Thermistor has no Polarity)
3. Close the hot Soldering Tip to the Thermistor (make sure not to touch the Thermistor, as it will damage the Thermistor’s package).
4. Note the Multimeter Display, the Resistance value will rise in proportion to the high temperature around it.

How to Measure Thermistor NTC(Negative Temperature Coefficient)

1. Set the Multimeter Switch Position at ohm position (Ω)
2. Connect the Probe on the Thermistor’s Leg (Thermistor has no Polarity)
3. Close the hot Soldering Tip to the Thermistor (make sure not to touch the Thermistor, as it will damage the Thermistor’s package).
4. Note the Display on multimeter, the resistance value will drop in proportion to the high temperature around it.

Thermistor is declared damaged or unable to function as it should if when the measurement occurs conditions such as the following:

• The value on the Multimeter is always in the position “0” when measured, this means that the Thermistor is “Short” or occurs a “short relationship”. The value on the Multimeter is always in the position of “Infinity” when measured, this means that the Thermistor is “Open” or “Broken”.
• The value on the Multimeter is unstable or indicates at a certain value but does not go down or up so the Thermistor is also in a damaged condition.

If we want to find out if the type of Thermistor measured is a type of PTC or NTC Thermistor, then we can find out by reading the resistance value of the Thermistor in question at the time of measuring. If the resistance value rises at hot temperatures, then the Thermistor measured is the PTC Type Thermistor. Meanwhile, if the receipt value decreases when the temperature around it is high (hot) then the thermistor type is NTC.

To more precisely and clearly know the characteristics of the Thermistor we can read the data sheet provided by the Manufacturer by downloading the data sheet from the manufacturer’s website. Also read: Thermistor (PTC/NTC) and its Characteristics.