IEEE 389-2020

This recommended practice presents a number of tests for use in determining the significant parameters and performance characteristics of electronics transformers and inductors. These tests are designed primarily for transformers and inductors used in all types of electronics applications. Even though these tests may be useful to the other types of transformers used in power distribution applications in utilities, industry, and others, the tests discussed in this document may supplement or complement the tests, but are not intended to replace the tests in standards for transformers, such as those in the IEEE C57 series of standards. Some of the tests described are intended for qualifying a product for a specific application, while others are test practices used for manufacturing and customer acceptance testing. The tests described in this recommended practice include those most commonly used in the electronics transformer industry: electric strength, resistance, power loss, inductance, impedance, balance, ratio of transformation, and many others used less frequently.

The following are the specific types of transformers and inductors to which this recommended practice is applicable: a) Electronic power: 1) Power, 2) Isolating, 3) Current limiting, 4) Rectifier, 5) Combination (rectifier and filament), 6) Ferroresonant, 7) Converter, 8) Polyphase, 9) Switch mode, 10) Magnetic amplifiers; b) Large rectifiers; c) Pulse: 1) Voltage stepdown, 2) Voltage stepup, 3) Low ratio inverting, 4) Low power pulse, 5) Square-loop, d) Broadband, 1) Impedance matching, 2) DC insulating, 3) Common-mode rejection, 4) Potential transformers, 5) Current transformers, 6) Filter inductors, 7) Charging inductors, 8) Hybrid transformers

Revision Standard - Active. A number of tests are presented for use in determining the significant parameters and performance characteristics of electronics transformers and inductors. These tests are designed primarily for transformers and inductors used in all types of electronics applications, but they may apply to the other types of transformers of large apparent-power rating used in the electric power utility industry.