Temperature Curves

North Star Sensors offer six R-T curves to select from. Which R-T curve to select depends on a variety of parameters such as response time, application temperature range, and finished coated dimensions. If needed, North Star Sensors application engineers will help you select the optimal R-T curve material for your application. North Star Sensors R-T curves are named after the NTC (Negative Temperature Coefficient) value at 25 °C. For example, Curve 44 has an NTC value of -4.4%/° C at 25 °C.

  
    Curve:
    44
    35
    38
    40
    43
    47
  

    0 ̊C / 70 ̊C Ratio:
    18.65
    10.38
    12.96
    14.82
    17.73
    22.64
  

    25 ̊C / 85 ̊C β:
    3978
    3192
    3486
    3694
    3943
    4262
  

    Resistance Range:
    1 kΩ - 100 kΩ
    50 Ω - 500 Ω
    150 Ω - 1.5 kΩ
    5 kΩ - 50 kΩ
    20 kΩ - 50 kΩ
    10 kΩ - 150 kΩ
  

Go to page Calculating Temperature from Resistance for more details about Ratio and Beta value β.

Curve 44

1 °C Rt / R25 Table (.pdf)
R/T Specifications (.pdf)
Ω vs °C Calculator (.xlsx)

One of the most versatile and widely specified materials, it is available in a variety of physical configurations, including standard tip ODs, mini ODs and micro ODs.

Generally, R25 values for Curve 44 fall within the range of 1 kΩ to 100kΩ.

R25 values for Curve 35 typically fall within the range of 50 Ω to 500 Ω which is useful for low temperature measurements.

Curve 35

1 °C Rt / R25 Table (.pdf)
R/T Specifications (.pdf)
Ω vs °C Calculator (.xlsx)

Curve 38

1 °C Rt / R25 Table (.pdf)
R/T Specifications (.pdf)
Ω vs °C Calculator (.xlsx)

R25 values for Curve 38 typically fall within the range of 100 Ω to 1.5k Ω which, like Curve 35, is useful for low temperature measurements.

The Curve 40 10k Ω thermistor is widely used in certain industries. R25 values are available in range of 5 kΩ to 50 kΩ

Curve 40

1 °C Rt / R25 Table (.pdf)
R/T Specifications (.pdf)
Ω vs °C Calculator (.xlsx)

Curve 43

1 °C Rt / R25 Table (.pdf)
R/T Specifications (.pdf)
Ω vs °C Calculator (.xlsx)

Curve 43 is used where a high resistance, smaller-sized thermistor is desired. Typically, R25 values for Curve 43 fall within the range of 20 kΩ to 50 kΩ but it can be offered in a value as low as 5 kΩ.

Curve 47

1 °C Rt / R25 Table (.pdf)
R/T Specifications (.pdf)
Ω vs °C Calculator (.xlsx)

With R25 values as high as 150 kΩ, Curve 47 can be ideal for low-power consumption [battery-powered] applications. R25 values range between 10 kΩ to 150 kΩ.