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Auto Transformers

  • Standard Design
  • Recognized to UL506
  • C-UL Certified to CSA C22.2 No. 66
  • From 250 VA to 1000VA
  • Other Power Ratings Available on Request
  • UL File E-161696






Auto Transformers

Using an auto-transformer is always an economical solution when you need to step down the voltage from 230V to 120 V or vice versa, and the equipment already has a fully isolated transformer or when the components do not require an isolated transformer.

The toroidal construction of an auto-transformer offers important advantages in comparison with an E/I lamination core transformer, like smaller physical size and weight, 30-70% reduction (depending on secondary voltage) and very low magnetic strayfields. The auto-transformer can be mounted horizontally using a steel washer or our Poly-Mount, a plastic insert, or an epoxy potted center with a 1/4" mounting hole. See our Mounting and Hardware page for more information.

With its small size and weight, the auto-transformer can be installed easily in existing equipment or supplied in an optional enclosure with or without cord, plug and receptacle.


Part No.
Temp. Rise at
Full Load
Step-Up From 120V to 230V, 60 Hz Operation
PriceA56152500.7W45ºC3.9 x 1.799 x 432.61.2
PriceA56165001.2W55ºC4.5 x 1.9114 x 494.21.9
PriceA56177501.5W58ºC5.0 x 2.3127 x 595.82.6
PriceA561810002.0W63ºC5.5 x 2.3140 x 597.13.2
Step-Down From 230V to 120V, 50-60Hz Operation
PriceA56202500.7W54ºC3.7 x 1.894 x 462.61.2
PriceA56215001.3W50ºC4.5 x 2.2114 x 564.82.2
PriceA56227501.7W55ºC5.5 x 2.1140 x 536.52.9
PriceA562310002.3W56ºC5.5 x 2.5140 x 648.33.8

Mounting Options

Step-Up from 120V to 230V, 60Hz Operation
Part No.Poly-MountL-BracketOmega BracketWashers & Pads
Step-Down from 230V to 120V, 50-60Hz Operation
Part No.Poly-MountL-BracketOmega BracketWashers & Pads

Terms and Conditions

  • For larger quantity prices, please contact the factory directly.
  • Prices and data subject to change without prior notice
  • Delivery: Small quantities of standards are normally available from stock
  • 30-Day Return Policy of Undamaged Items - 15% Restocking Fee on Standard Transformers
  • 36 Month Product Warranty
  • Terms and Conditions