reostada

Reostada is sometimes encountered as an alternative or mistaken spelling for rheostat, a type of variable resistor used to control electrical current in a circuit. The standard term in English is rheostat; in Spanish the device is called reóstato and in Portuguese reóstato. The form reostada is not common in technical literature and may reflect transliteration or spelling variation rather than a distinct device.

A rheostat consists of a resistive element, typically a coil of wire wound on a ceramic or insulating core, with a movable contact (a wiper or slider) that taps into the element. By turning a knob or moving a lever, the contact slides along the resistive path, changing the effective resistance and thus the current flowing through the circuit. This allows adjustable control of power delivery to components such as lamps, motors, or test circuits.

Construction and types vary, but common designs include wire-wound rheostats with high power handling and robust mounting, and compact slider-type rheostats for lower currents. Rheostats are designed to dissipate heat generated by current flow, requiring adequate ventilation and insulation.

In modern electronics, rheostats have largely been supplanted by solid-state regulators and digitally controlled power supplies for precision and efficiency. They remain in use in some high-current or educational settings where simple, rugged, manually variable resistance is advantageous.

See also: potentiometer, variable resistor, power resistor, electric regulator.