A power cord, line cord, or mains cable is a cord or cable that temporarily connects an electrical appliance to the distribution circuits of an electrical power source via a wall socket or extension cord.
The terms are generally used for cables using a power plug to connect to a single-phase alternating current power source at the local line voltage—generally 100 to 240 volts, depending on the location). The terms power cable, mains lead or flex are also used. A lamp cord is a light weight ungrounded two wire cord used for small loads such as a table or floor lamp. The term cord set is also used to distinguish those cords that include connectors molded to the cord at each end.
Power cables may be either fixed or detachable from the appliance. In the case of detachable leads, the appliance end of the power cord has a socket (female connector) rather than a plug (male connector) to link it to the appliance, to avoid the dangers from having a live protruding pin. Cords may also have twist-locking features, or other attachments to prevent accidental disconnection at one or both ends. A cord set may include accessories such as fuses for overcurrent protection, a pilot lamp to indicate voltage is present, or a leakage current detector. Power cords for sensitive instruments, or audio/video equipment may also include a shield over the power conductors to minimize electromagnetic interference.
IEC power cables come in high-temperature and low-temperature variants, as well as various current capacities. The connectors have slightly different shapes to ensure that it is not possible to substitute a cable with a lower temperature or current rating, but that it is possible to use an over-rated cable. Cords also have different types of exterior jackets available to accommodate environmental variables such as moisture, temperature, oils, sunlight, flexibility, and heavy wear. For example, a heating appliance may come with a cord designed to withstand accidental contact with heated surfaces.
World-wide, more than a dozen different types of connectors are used for fixed building wiring. Products sold in many different markets can use a standardized IEC connector and then use a detachable power cord to match the local electrical outlets. This simplifies safety approvals, factory testing, and production since the power cord is a low-cost item available as a commodity. Note that the same types of appliance-side connectors are used with both 110 V and 230 V power cables, so care must be used when moving appliances between countries with different voltage standards — substituting a power cord that matches local power outlets will result in an incorrect voltage being applied to the appliance or equipment. Some devices have a slide-switch to adapt to different voltages, or wide-ranging power supplies. Unless explicitly labelled as capable of handling local voltages, this is very likely to damage or destroy the appliance.