How to distinguish whether a cable is an outside line or an inside line?

How to distinguish cables from external lines and internal lines;

1, conductor: It is composed of one or more flexible conductors covered with a light and soft sheath, and is used as a current-carrying conductive metal conductor. There are many forms such as solid, twisted or foil woven, which are divided into bare wires and insulated wires according to the insulation situation.

2. The internal wires do not include any insulated or protective wires. Besides being used as a conductor for transmitting electric energy and information, it can also be used to manufacture parts and connecting wires of motors and electrical appliances. Generally made of copper, aluminum, copper alloy, aluminum alloy, copper-clad steel, aluminum-clad steel and other composite metal materials. In addition to good electrical conductivity, bare wires also have certain mechanical properties, such as tensile strength, elongation, bending and torsion characteristics, creep resistance and wear resistance.

3. Cable: an insulated conductor consisting of one or more insulated core wires placed in a sealed sheath. It can be covered with a protective coating for transmitting, distributing electric energy or transmitting electrical signals. The main difference between it and ordinary wires is that the cable is larger in size and more complicated in structure.