Type J (Iron/Constantan)
Type J is the oldest thermocouple and has a large installed base. It has a good range up to 760°C. One leg is Iron and is subject to corrosion in moist or Oxygen atmospheres. It can be used in Reducing, Vacuum and Inert atmospheres.
Chemical Composition, %
|TYPE||EMF Versus Pt.67(mV)|
Physical and Mechanical Properties (RT, Annealed)
|Type||Density, g/cm³||Melting Point, ℃||Tensile Strength, MPa||Elongation, %||Resistivity, μΩ.m|
- Good resistance to oxidation
- High EMF output against Platinum 67
- Good temperature accuracy, sensitivity and stability
Type J Thermocouple is recommended for vacuum, oxidizing, reducing or inert atmosphere, but it can’t be used in sulphurous atmosphere above 500℃.