Few things to check before selecting RTD

RTD can be used as a sensor in the following applications:

  • Cooling services like refrigeration and air conditioning
  • Exhaust Gas temperature measurement
  • Food processing
  • Textile, Plastics and Petrochemical Industries
  • Fluid Temperature measurements
  • Microelectronics, etc.
When should we use RTD in particular?
  • When accuracy, stability and linearity are major requirements.
  • When good accuracy is expected over a large temperature range.
  • When point sensing, and not area sensing is the motive.
  • When cost and complicated circuit is not a major issue.
  • When temperature change to be sensed is not too small and response time is not an issue;
    if otherwise, thermistor is preferred.
Checklist of specifications for RTD:
  1. Base Resistance Value
  2. Temperature Coefficient of Resistance (TCR)
  3. Range
  4. Housing Material
  5. Calibration Standards
  6. Configuration (2/3/4 wire)
  7. Class of RTD (A/B/C/DIN as per IEC-751)
  8. Insulation Resistance
  9. Element (Pt/Ni/Cu)
  10. Type of winding (Wire wound/Thin film)
  11. Probe diameter & length
  12. Thread size (e.g 1/8" NPT) 
  13. Accuracy
  14. Material of sheath & length of lead wires
  15. Cost

    For further information about RTD:

    Types and Classes of RTD                                        What is RTD?                            

    Related Articles:

    Temperature Units & Conversions                                       Thermocouple