Autoptransformatorin

Autoptransformatorin is not a standard term in electrical engineering; it likely refers to an autotransformator (German: Autotransformator). An autotransformer is a transformer that uses a single winding acting as both the primary and secondary, with a portion of the winding common to both circuits. The output voltage is proportional to the taps on the winding, and the device can step voltage up or down. Because only one winding is used, autotransformers require less copper and core material than two-winding transformers of the same power rating, often making them smaller and cheaper at moderate power levels. However, they do not provide galvanic isolation between input and output, and the entire winding is energized whenever the device is connected, which increases risk in certain fault conditions.

Construction and operation: An autotransformer consists of a single continuous winding with taps. The input is applied across a portion of the winding, and the output is taken from another portion. The voltage ratio is determined by the relative number of turns between the taps. In a simple step-down, the output voltage is a fraction of the input; in step-up configurations, the output exceeds the input.

Applications: Autotransformers are commonly used for voltage regulation and starting large motors in industry, for providing lower-voltage supplies in instrument power sources, and in adjustable power supplies such as Variacs. They are favored for efficiency in appropriate power ranges but are avoided where electrical isolation is required.

Safety and limitations: Designers must consider the lack of isolation, the possibility of voltage on common windings, and applicable standards.