How Thick Should Jumper Cables for Cars Be?

[VonCharles]

Automotive jumper cables typically use 2.0 or 2.5 gauge pure copper national standard wires, with 16 square millimeter copper wires being sufficient. The starting current is very high, while the normal operating current is several tens of amperes. The thickness of the wires is specified by models, generally calculated in square millimeters, and is usually labeled on automotive circuit diagrams. The main difference between wires lies in the amount of current they can pass per unit time. At a certain voltage, thinner wires carry less current, while thicker wires can handle larger currents, so using thin wires is not advisable. Battery connection cables must handle starting or charging currents; generally, starter motor power requires wires of 25 square millimeters or more, while charging cables typically use 6 square millimeters. Battery cables consist of two separate wires, and charging connection cables are integrated into the wiring assembly.