Autovolt electric manufactures 2a, single phase, open type variable autotransformers with a single layer winding on toroidal core of high grade cold rolled grain oriented steel. By the adjustment of the position of the brush any desired voltage can be obtained. This open type autotransformer is useful for applications in supplying voltage adjustment; manual or automatic boosting of low lines and line voltage stabilisation in automatic voltage stabilizer; over and under voltage testing of electrical and electronic equipment; heat controlling of ovens, furnaces, infra-red heaters; testing and calibration of voltmeters, ammeters, watt meters; and built in as an integral control element in electrical, electronic and automatic control and process equipment. The single phase open type autotransformers are available with salient features offering advantages like rugged construction for heavy-duty trouble free operations; excellent regulation for lower drop in voltage from "no load" to "full load"; high efficacy for careful copper core selection and design assuring low watt loss compared to other controller types; no wave form distortion to provide an output voltage wave from faithful and distortion less replica of input voltage wave form; enhanced overload capacity due to careful designing; low operating torque by a glass smooth commutator, special sintered bushings for shaft and perfect assembling of coils result in low operating torque; smooth and linear output as voltage between turns is small; harmful sparkling is avoided as bush arm is in constant contact with more than one turn; and low maintenance and trouble free life.
