H. TINSLEY THERMOCOUPLE POTENTIOMETER Type 4606C, 1950's

A thermocouple consists of two junctions of dissimilar metals. If the two Junctions are at different temperatures a voltage is produced which, for small temperature differences and accuracy was measured using a potentiometer. To achieve absolute temperature measurement one of the junctions must be kept at a known temperature, often by melting ice.

The thermocouple potentiometer removes the inconvenience of having to use melting ice for each measurement by measuring the temperature of the reference junction. The measured temperature can then be corrected to the standard cold junction temperature of 0 degrees C.

Donated by John Barnes

• Basic operation of a thermocouple, measurement by a potentiometer with ice as a reference
  

A1486