maximum conductor current calculation
Any time that current flows through any conductor, a certain resistance or opposition is inherent in that conductor. This resistance will convert current to heat, and the heat further increases the conductor’s resistance (+ Temp. Coe. of R), causing more heat to be generated due to the opposition. As a result, a conductor must be chosen carefully for each application so that it can carry the current without developing excessive heat. This is achieved by selecting a conductor with a greater cross-sectional area to decrease its resistance. The National Fire Protection Association has developed a set of standards known as the American Wire Gauge for all copper conductors, which lists their diameter, resistance, and maximum safe current in amperes. This table is given in Table. A rough guide for measuring wire size is shown in Figure.
American wire gauge current chart
