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.
- Standard Committee
- PE/PSRCC - Power System Relaying and Control
- Status
- Superseded Standard
- Superseded by
- C37.112-2018
- Board Approval
- 1996-09-19
- History
-
- ANSI Approved:
- 1997-02-27
- Published:
- 1996-11-30
- Reaffirmed:
- 2007-03-08
Working Group Details
- Society
- IEEE Power and Energy Society
- Standard 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
Other Activities From This Working Group
Current projects that have been authorized by the IEEE SA Standards Board to develop a standard.
No Active Projects
Standards approved by the IEEE SA Standards Board that are within the 10-year lifecycle.
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.
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