Etal’s auto transformers are engineered for efficient voltage adjustment and regulation in applications where electrical isolation is not required. Featuring a single-winding design with precision tap configurations, they offer a compact, cost-effective solution with higher efficiency and reduced material usage compared to conventional transformers. Designed for industrial, commercial, and OEM applications, they deliver excellent voltage stability, low impedance, and reliable performance in motor starting, voltage conversion, and controlled power distribution systems.
What Is an Auto Transformer?
An auto transformer is designed with a single continuous winding that functions as both the primary and secondary circuit. This allows for smaller physical dimensions and a more economical overall design in cases where galvanically separated windings are not required.
Using a single-winding configuration, an auto transformer can achieve the same voltage and current transformation as a conventional two‑winding transformer, but with reduced material usage and improved efficiency.
Auto Transformer Design Characteristics
There are two fundamental design characteristics that distinguish an auto transformer from a traditional transformer:
- The secondary winding is common to both the primary and secondary circuits
- There is a direct copper connection between the primary and secondary circuits
These characteristics contribute to higher efficiency and reduced losses, while also meaning that auto transformers do not provide electrical isolation between input and output.
Typical Applications for Auto Transformers
Auto transformers are widely used in applications where efficient voltage conversion and regulation are required without isolation, including:
- Motor starting and reduced‑voltage motor control
- Voltage adjustment and conversion systems
- Industrial and commercial power distribution
- OEM equipment and machinery
- Controlled power and energy‑efficient systems
Their compact form factor and high efficiency make them especially suitable for space‑constrained and cost‑sensitive installations.
Choose Etal’s auto transformers for efficient voltage regulation, compact design, and dependable performance across demanding applications.
Auto Transformers Advantages
Auto transformers offer several technical and economic advantages when the voltage ratio is relatively low:
- Lower leakage reactance
- Reduced copper and core losses
- Smaller excitation current
- Compact size and lower overall cost
- Higher efficiency compared to dual‑winding transformers
These benefits are most pronounced when the voltage ratio is less than 2:1, making auto transformers an attractive solution for many industrial voltage adjustment applications.