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
- 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
- Sponsor Committee
- PE/PSRCC - Power System Relaying and Control
- Working Group
-
C37.112_WG - Inverse-Time Characteristic Equations for Overcurrent Relays
- IEEE Program Manager
- Malia Zaman
Contact Malia Zaman - Working Group Chair
- Randall Crellin
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These standards have been replaced with a revised version of the standard, or by a compilation of the original active standard and all its existing amendments, corrigenda, and errata.
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.
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