Active Standard

IEEE C37.112-2018

IEEE Standard for Inverse-Time Characteristics Equations for Overcurrent Relays

The inverse-time characteristics of overcurrent relays are defined in this standard. Operating equations and allowances are provided in the standard. The standard defines an integral equation for microprocessor relays that ensures coordination not only in the case of constant current input but for any current condition of varying magnitude. Electromechanical inverse-time overcurrent relay reset characteristics are defined in the event that designers of microprocessor based relays and computer relays want to match the reset characteristics of the electromechanical relays.

Sponsor Committee
PE/PSRCC - Power System Relaying and Control
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Status
Active Standard
PAR Approval
2017-03-23
Superseding
C37.112-1996
Board Approval
2018-12-05
History
Published:
2019-02-05

Working Group Details

Society
IEEE Power and Energy Society
Learn More About IEEE Power and Energy Society
Sponsor Committee
PE/PSRCC - Power System Relaying and Control
Learn More About PE/PSRCC - Power System Relaying and Control
Working Group
C37.112_WG - Inverse-Time Characteristic Equations for Overcurrent Relays
IEEE Program Manager
Malia Zaman
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Working Group Chair
Randall Crellin

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C37.112-1996
IEEE Standard Inverse-Time Characteristic Equations for Overcurrent Relays

The inverse-time characteristics of overcurrent relays are defined in this standard. Operating equations and allowances are provided in the standard. The standard defines an integral equation for microprocessor relays that ensures coordination not only in the case of constant current input but for any current condition of varying magnitude. Electromechanical inverse-time overcurrent relay reset characteristics are defined in the event that designers of microprocessor based relays and computer relays want to match the reset characteristics of the electromechanical relays.

Learn More About C37.112-1996

These standards have been removed from active status through a ballot where the standard is made inactive as a consensus decision of a balloting group.


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These standards are removed from active status through an administrative process for standards that have not undergone a revision process within 10 years.


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