Three-phase autotransformers

Purpose and design

3AT type three-phase autotransformers are a special variety of transformers in which the primary and secondary windings are not separated. Compared to transformers at the same power, autotransformers are lighter but have a much lower short circuit impedance. Autotransformers are used for voltage levels adjustment, powering low-power electrical equipment, motor start up. The winding of an autotransformer may have multiple voltage tap changers. The design of the device provides fixing by means of angle brackets screwed to the core. Upon agreement, autotransformers can be supplied in enclosures with the required protection class.

Upon agreement, we can manufacture a non- standard device with the required technical parameters.
The manufacturer reserves the right to make changes to the parameters due to technical product developments.

Technical Standards EN/IEC 61558-2-13
Power from 0,05 to 1600 kVA
Primary/secondary voltage up to 1000 V / up to 1000 V
Connection group YNa0
Frequency 50 / 60 Hz
Protection class IP00
Insulation class F (155°C)
Ambient temperature from -250C to +400C
Environment class C1/E0 – land based, C2/E1 – mining and offshore
Protection class class I
Mounting by means of brackets