This application guide applies to the ac highvoltage circuit breakers rated in accordance with the methods given in ANSI/IEEE C37.04 1979@ Schedules of Rating Structure for AC High-Voltage Circuit Breakers@ and listed in ANSI C37.06-1979@ Preferred Ratings and Related Required Capabilities for AC High-Voltage Circuit Breakers Rated on a Symmetrical Current Basis. Circuit breakers rated and manufactured to meet other standards@ or used in switchgear assemblies@ should be applied in accordance with application procedures adapted to their specific ratings or applications. Purpose This guide is intended for general use in the application of circuit breakers. Familiarity with other American National Standards applying to circuit breakers is assumed@ and provisions of those standards are indicated herein only when necessary for clarity in describing application requirements.