Red Seal Instrumentation and Control Technician Exam 2026 – 400 Free Practice Questions to Pass the Exam

An RTD, or Resistance Temperature Detector, is a type of temperature sensor that operates on the principle that the electrical resistance of a conductor changes with temperature. RTDs are made from pure materials, typically platinum, which provides a precise and repeatable relationship between resistance and temperature. This makes them widely used in industrial applications for accurate temperature measurement.

RTDs offer excellent linearity, stability, and reproducibility, making them ideal for environments where precise temperature readings are crucial. They are commonly used in various processes, including HVAC systems, manufacturing, and scientific research, where maintaining the correct temperature is essential for efficiency and safety.

The other choices relate to different types of equipment: a signal amplifier boosts signal strength, a data logging device records data for analysis over time, and a variable frequency drive regulates the speed of an electric motor. Each of these devices serves distinct purposes, but they do not perform the temperature measurement functions characteristic of an RTD.