IEEE 449-1990

This standard pertains to ferroresonant voltage regulators that operate at relatively constant frequencies and provide substantially constant output voltages in spite of relatively large changes of input voltage, and to controlled ferroresonant regulators that maintain substantially constant output voltages regardless of variations, within limits, of input voltage, temperature, frequency, and output load. Guides to application and test procedures are included. Provision is made for relating the characteristics of ferroresonant regulators to associated rectifiers and circuits. Definitions pertaining to ferroresonance and ferroresonant regulators that have not been found elsewhere are included with an appropriate discussion. This standard includes, but is not limited to the following types of ferroresonant regulators: (1 ) Series ferroresonant regulators (2) Series-parallel ferroresonant regulators (electrically connected) (3) Ferroresonant transformer regulators (magnetically coupled) (4) Controlled ferroresonant regulators

The purpose of this standard is to provide a common ground of understanding between engineers involved in the design, manufacture, sale, and use of ferroresonant transformers. It pertains to ferroresonant transformers used as regulators in electronic power supplies and in other equipment where the inherent properties of voltage regulation and current limiting are useful.

Revision Standard - Inactive-Withdrawn. Requirements are provided for ferroresonant voltage regulators that operate at relatively constant frequencies and provide substantially constant output voltages in spite of relatively large changes of input voltage. Requirements for controlled ferroresonant regulators that maintain substantially constant output voltages regardless of variations, within limits, of input voltage, temperature, frequency, and output load are also included. The requirements cover definitions, symbols, and circuit schematics; service conditions; ratings; nameplate and other markings; testing; application; and maintenance. Provision is made for relating the characteristics of ferroresonant regulators to associated rectifiers and circuits.