“30k NTC thermistor” describes a nominal resistance of 30 kΩ at a specified reference temperature. It does not, by itself, identify the resistance-temperature curve, tolerance, operating range or probe assembly. Confirm the exact part’s datasheet before using the rating to select or replace a sensor.
Confirm the 30k reference point
Check the resistance value and its reference temperature in the manufacturer’s datasheet. A reference of 25°C is common for NTC thermistors, but it should not be assumed for an unidentified part. NTC resistance falls as temperature rises, and two parts rated 30 kΩ can have different resistance values at other temperatures.
Compare the complete resistance-temperature curve
Use the manufacturer’s resistance-temperature table or equation for the intended measurement range. Record the beta value and its defining temperature interval, along with resistance tolerance and beta tolerance. A beta value without its interval is incomplete, and a nominal 30k match alone cannot confirm controller compatibility. See the NTC thermistor beta value guide for curve selection context.
Check the controller and installation
Confirm the controller input range, bias/reference resistor, measurement current and firmware conversion method. Consider wiring resistance, thermal contact, self-heating and calibration or verification requirements in the final installation. For a probe assembly, also define sensor dimensions, mounting, cable, connector, insulation and exposure to moisture, vibration or chemicals.
Information to provide for an OEM review
- 30 kΩ nominal resistance and reference temperature.
- Required resistance-temperature curve or beta value with its temperature interval.
- Operating range and resistance/beta tolerance targets.
- Controller input details and calibration or validation method.
- Probe or bead drawing, mounting, cable and connector requirements.
- Environmental conditions, sample quantity and production forecast.
Review our NTC thermistor range and send your curve, controller and assembly requirements for an OEM review.
Technical reference
TDK Electronics’ NTC thermistor technical information describes resistance-temperature characteristics and beta values.
