C is an abbreviation for Centigrade, a temperature scale where water freezes at 0°C and boils at 100°C under standard atmospheric pressure. The scale is more commonly referred to today as the Celsius temperature scale.
The Centigrade scale, now formally recognized as Celsius, is widely used in science, engineering, and manufacturing worldwide. In the wire and cable industry, temperature ratings expressed in °C are critical for assessing product performance and safety. Cable insulation, jackets, and shielding materials are rated based on how well they withstand heat without degrading or losing dielectric integrity. Common specifications may list operating ranges such as -20°C to 105°C, or higher for specialized constructions. Understanding the °C scale ensures accuracy when evaluating product data, conducting thermal testing, or confirming regulatory compliance.
The Celsius scale is part of the International System of Units (SI), maintained by the International Bureau of Weights and Measures (BIPM). In the wire and cable sector, organizations such as UL, IEC, and IEEE use °C ratings to define insulation, jacket, and component temperature performance.
The Centigrade scale was created in 1742 by Swedish astronomer Anders Celsius. Originally inverted, with 0 representing boiling and 100 representing freezing, it was later corrected to the current format. In 1948, the 9th General Conference on Weights and Measures officially adopted “Celsius” as the proper term, replacing “Centigrade,” though the abbreviation C remains common in technical contexts.