Three-phase autotransformers


Autotransformer is a special variation of transformer in which primary and secondary windings are connected and therefore there is no galvanic separation between circuits. Autotransformers are used to connect networks with different voltage levels. They are also used in starting systems and in systems whereever a lack of electrical separation between primary and secondary circuits is allowed. The undoubted advantage of the autotransformer is that compared to the transformer of the same outgoing power they are smaller, lighter and cheaper..

Technical data

Design Three-phase autotransformers EA3 are produced in accordance with requirements of standard: EN/IEC 61558-2-1
Insulation class

B(130oC) - standard up to 5 kVA; F(155oC) - standard above 5 kVA

Climatic class/
Environmental class

C1/E0 - land design; C2/E1 - maritime design

Ambient temperature 40oC
Protection degree IP 00 lub IP 23
Protection class I
Frequency 50/60 Hz
Primary voltage up to 1000 V
Secondary voltage up to 1000 V
Fastening by means of angles