What is the use of the autotransformer???

Question

What is the use of the autotransformer???

Answer 1

Its a cheap, single winding transformer. Its common in uses where isolation is not required and voltage fluctuations are not critical. Most applications require isolation so the auto-transformer is not suitable and more expensive transformers with two windings have to be used.

Small ones are often found in fluorescent lights to power 240v ballasts from 120v.

Answer 2

It is generally used to boost the voltage of the AC mains, when the power company is providing a lower-than-normal voltage (for whatever reason).

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