Question

You have 2 Type T sensing junctions connected in parallel. One junction is at 200 F and the other sensing junction is at 350 F. The two thermocouples are connected to a CR1000 which is at 70 F. What will be the sensed voltage

Answer 1

We can use the standard table given at NIST. From table we get at 70 F which is 21.11 degree celsius, the generated voltage is 0.8344 mV. This is our reference voltage. For junction 1 the temperature is 200 F which is 93.33 degree celsius, which gives a voltage of 3.9681 mV. Therefore the sensed voltage is,

Similarly for the second thermocouple is the voltage due to the 280 F which 137.78 degree celsius is 6.0959 mV Therefore the sensed voltage is,

This is the reference NIST table used : (vertical is at 10 degree increments and horizontal is for the values in between the 10 values, for example you want to get voltage at 23 degrees, then you have to go to 20 in vertical and then go to 3 in the horizontal, the corresponding value will be the generated voltage)