Adequate isolation between a power source and a user of electronic equipment ensures the protection of that equipment. Given the high voltages that exist in modern electronic equipment, proper isolation protects an operator from contact with excessive electrical energy when the short circuits occur in the equipment. Isolation transformers have represented a usual solution for providing high isolation in electronic circuitry. Even with the increased use of well-organized, switched-mode power supplies (SMPS), isolation transformers can improve the overall isolation of an electronic design without severe penalties in added size, weight, and cost.

Isolation transformers offer an effective means of meeting the requirements of domestic and international security standards for electronic equipment. In the United States, for instance, such standards are set by the Occupational Safety and Health Administration (OSHA), with product testing performed according to appointed laboratories, such as Underwriters Laboratories (UL). All through Europe, safety standards are established by the International Electrotechnical Commission (IEC), with testing performed by the laboratories of individual member nations, such as the Verband Deutscher Electrotechniker (VDE) in Germany.