Type E thermocouple

Calculate the amount of voltage “seen” by the voltmeter given the following measurement and reference junction temperatures:

• T1 = 233 ^oC ; T2 = 31 ^oC ; T3 = 25 ^oC ; Vmeter = __________ mV
• T1 = 348 ^oC ; T2 = 40 ^oC ; T3 = 16 ^oC ; Vmeter = __________ mV
• T1 = −161 ^oC ; T2 = −4 ^oC ; T3 = 23 ^oC ; Vmeter = __________ mV
• T1 = 836 ^oC ; T2 = 34 ^oC ; T3 = 19 ^oC ; Vmeter = __________ mV

Answer :

All answers based on ITS-90 thermocouple table values:

• T1 = 233 ^oC ; T2 = 31 ^oC ; T3 = 25 ^oC ; Vmeter = 14.395 mV
• T1 = 348 ^oC ; T2 = 40 ^oC ; T3 = 16 ^oC ; Vmeter = 23.856 mV
•  T1 = −161 ^oC ; T2 = −4′^oC ; T3 = 23 ^oC ; Vmeter = −9.039 mV
• T1 = 836 ^oC ; T2 = 34 ^oC ; T3 = 19 ^oC ; Vmeter = 62.701 mV

Note: all temperatures at T2 are irrelevant because this is a junction between similar metals (type E wires connecting to corresponding type EX extension wires). The reference (cold) junction is where the type EX wires connect to copper, at temperature T3.