What is Kelvin?

Kelvin Four-terminal sensing ^[1] is also known as 4T sensing, 4T sensing, or 4-point probe method. It is an electrical impedance measurement technology. Separate counter current and voltage detection electrodes enable more accurate measurements than traditional two-terminal (2T) sensing. Kelvin four-wire detection is used in some ohmmeters and impedance analyzers, and in wiring configurations for precision strain gauges and resistance thermometers. It can also be used to measure the sheet resistance of thin films. The key advantage of four-wire detection is the separated current and voltage electrodes, eliminating the impedance of wiring and contact resistance.