High accuracy temperature measurement RTDs versus NTC thermistors

摘要

Industry demands coupled with improved measurement and control systems are fuelling calls for improved temperature sensor accuracy. Systems designers have two preferred alternatives, although others are available, for applications in the range of -50℃ to +250℃. These are RTDs (Resistance Thermometer Detectors) and NTC (Negative Temperature Coefficient) thermistors. RTDs, usually Pt100 or Pt1000 sensing resistors, offer ultimate accuracy over a wide temperature range. They are generally rather more expensive than NTC thermistors and have a lower sensitivity. However, RTDs are almost universally interchangeable worldwide. NTC thermistors are high sensitivity devices with a restricted temperature range.