The same resistance at one temperature does not mean the same curve. B-value, tolerance and characteristic may vary throughout the working range.

What to check out

• Compare data sheets of both sensors: R at reference temperature, B and the interval for which it is given.
• Repeat the measurement at several known temperatures and wait for the thermal balance.
• Separate the systematic deviation from poor contact, self-heating and differences in the measurement site.
• Use appropriate tables or coefficients in your own program. In the case of an existing controller, use a sensor appropriate to its setting.

A Practical Example

If the sensors match at room temperature but not in a cold environment, a single correction of the deviation often does not correct the difference across the range.

Common error

Calibration at one point is not a confirmation of the entire area. Do not declare the typer defective until you have verified that you compare equivalent performance.

For further reading

• Vishay: curves R-T and coefficients NTC-terminators (English). The NTC section provides explanations of temperature curves, coefficients and measurement conditions.

Compatibility check products

Select products according to the above criteria; the list is not a confirmation that they are all interchangeable.

• Inox probe NTC sensor for a temperature of 10K 0,5m cable
• 100K ohm NTC 3950 Thermistor for 3D printers universal
• 3D Printer NTC Thermoistor 100 K accuracy 1 percent