Single-phase autotransformer

E.F.C. manufactures single-phase autotransformers tailored to specific customer requirements. We can build custom autotransformers for standard voltages, i.e. 380V and 220V (400V and 230V) or any other voltage required by the customer, including both step-down and step-up transformers (e.g. 220/380V or 220/110V).

An autotransformer (step-up or step-down) is a transformer in which the primary and secondary windings are physically connected together. This feature means an autotransformer can be smaller than a comparably-rated transformer.  On the outside, it looks similar to a normal transformer.

On the other hand, having the primary and secondary windings connected to each other means an autotransformer cannot be used where the primary circuit and the secondary circuit need to be isolated from one another.

There are also single-phase variable output autotransformers (called ‘single-phase variacs’) which are used where the supply voltage needs to be variable,  for example, to carry out equipment testing or in voltage stabilisers.

The single-phase autotransformers we supply are designed and manufactured with the following characteristics:

  • Primary voltage: as per customer specification.
  • Secondary voltage: as per customer specification.
  • Frequency: 50-60 Hz.
  • Operating temperature: 40 °C.
  • Protection class: IP00 (exposed).
  • Insulation class: F (155 °C).
  • Isolation test voltage: 5000 V.

Please do not hesitate to contact us for a quote and any other price information concerning our products.


Construction features

During the autotransformer design and engineering stage, we focus particular attention on achieving as compact a product as possible.

Using high-quality materials and advanced manufacturing technologies has allowed us to create particularly small autotransformers which comply fully with thermal, electrical, and regulatory requirements.

Generally speaking, all our autotransformers are produced in exposed versions (IP00 protection class – no special protection) but they can also be supplied in steel plate housings with protection class IP23 or other level of protection.

Get in touch to find out more about our products. Our specialist staff are on hand to provide you with all the information you need.


Adaptation of mains voltage

Our company manufactures and sells a wide range of single-phase autotransformers suitable for mains voltage adaptation applications.

Not only that, over the years, we have successfully designed single-phase autotransformers for the most diverse uses and continue to do so to the satisfaction of our customers.

Get in touch to find out more about our products and ask for a quote or price information. Our specialist staff are on hand to provide you with all the information you need.