What is the difference between a regular transformer and an isolation transformer? What is an autotransformer?

FA123708

23 August 2021

Issue:
Clarification of the difference between an Isolation Transformer and an Autotransformer

Product Line:
LV Transformers

Environment:
Definition applies to all Transformer Products from SquareD/Schneider Electric

Cause:
The distinction between an Isolation Transformer and an Autotransformer is required for proper application

Resolution:
Any two winding transformer where the primary and secondary are not electrically connected is an isolation transformer.
In contrast, an autotransformer has a physical, electrical connection between the primary and secondary.