Type J Thermocouple (Iron/Constantan)

Type J Thermocouple

The type J is also very common. It has a smaller temperature range and a shorter lifespan at higher temperatures than the Type K. It is equivalent to the Type K in terms of expense and reliability.

Type J Temperature Range:

Thermocouple grade wire, -346 to 1,400F (-210 to 760C)
Extension wire, 32 to 392F (0 to 200C)

Type J Accuracy (whichever is greater):

Standard: +/- 2.2C or +/- .75%
Special Limits of Error: +/- 1.1C or 0.4%

Consideration for bare wire type J thermocouple applications:

The Type J Is Well Suited To Oxidizing Atmospheres