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C57.109-1985 - IEEE Guide for Transformer Through-Fault-Current Duration

Description: Protective devices such as relays and fuses have well-defined operating characteristics that relate fault magnitude to operating time. It is desirable that these characteristic curves be coordinated with a comparable curve(s) applicable to transformers that relate duration and fault magnitude to withstand capability. This guide sets forth recommendations believed essential for the application of overcurrent protective devices applied to limit the exposure time of transformers to short-circuit current (see ANSI/IEEE C37.91-1985).
  • Status: Superseded Standard Help

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