Which device is used to measure TOT for engine thermocouples?

• A. Thermocouple
• B. Pressure Transducer
• C. Accelerometer
• D. Pitot Tube

Answer: (A)

Turbine Outlet Temperature is a temperature measurement in the hot exhaust path, so you need a sensor that directly senses temperature. A thermocouple fits this role because it produces a voltage that corresponds to the temperature at its sensing junction, and it’s built to withstand the high temperatures of turbine exhaust with good response time. This makes it the appropriate tool to measure TOT.

The other devices measure different physical quantities: a pressure transducer measures pressure, an accelerometer measures acceleration or vibration, and a Pitot tube measures flow-related pressure or airspeed. They don’t provide temperature information, so they aren’t used for TOT.