What is TCR or Temperature Coefficient of Resistance?
Every wire material has a specific resistivity. As a wire heats up, its resistance will increase in a predictable way based on its TCR.
TCR for a material is usually measured by the wire manufacturer using MIL-STD-202 Method 304, which uses a series of test temperatures. The first series is 25°, 0°, -15°, and -55°C; the second series are 25°, 50°,75°, 100°, 125°, 200°, 275°, and 350°C. The lowest test temperature in the first series, and the highest test temperature in the second series, are used as two points to create a linear TCR value.
