42-volt electrical system

rdf:langString 42-volt electrical system

rdf:langString In automobiles, a 42-volt electrical system was an electrical power standard proposed in the late 1990s. It was intended to allow more powerful electrically-driven accessories, and lighter automobile wiring harnesses. Electric motors were proposed to be used for power steering or other systems, providing more compact installations and eliminating the weight of drive belts or large wires for high-current loads. The proposed new standard was exactly triple the voltage of existing "12-volt" systems. The higher voltage was selected to provide greater power capacity for wiring and devices on one hand, and to stay under the 50-volt limit used as a guideline for electric shock hazard. The European auto manufacturer Daimler-Benz proposed a 42V brand name for the conversion. Although many manufacturers were predicting a switch to 36-volt (lithium-ion battery) / 42-volt (charging voltage) electrical systems, the changeover has not occurred, and the plans appear to have been canceled. The availability of higher-efficiency motors, new wiring techniques and digital controls, and a focus on hybrid vehicle systems that use high-voltage starter/generators has largely eliminated the push for switching the main automotive voltages. Applications that once were thought to require higher voltages, such as electrical power steering, have now been achieved with 12-volt systems. 42-volt electrical components are now used in only a few automotive applications, since incandescent light bulbs work well at 12 volts and switching of a 42-volt circuit is more difficult. 48-volt systems are being deployed in mild hybrid vehicles, which add electric assistance to the propulsion and regeneration during braking for fuel savings.