Protective Relay Settings: device function
dev50 to dev52
Protective relay settings, coordination parameters, and motor/bus protection data per IEEE C37, IEEE 242, IEC 60255, and IEEE 3004 series. Covers: IEEE C37.112 inverse time-overcurrent curve constants (A, B, p, tr) and IEC 60255-151 constants (k, alpha); CT accuracy classes C100/C200/C400/C800 per IEEE C57.13; relay pickup guidance by ANSI device number; CTI per IEEE 242; motor nameplate voltages, surge withstand levels, vibration limits, and relay alarm/trip thresholds per IEEE 3004.8-2016; ANSI device function numbers for motor and bus protection (Tables B.1/B.2/B.3); online partial discharge assessment thresholds; and dual-tie bus differential CT scheme fault response results per IEEE 3004.11-2019.
| parameter type | record id | device number | iec 61850 logical node | nema designation | protection function | source table | standard |
|---|---|---|---|---|---|---|---|
| device function | dev50 | 50 | PIOC | — | Instantaneous overcurrent or rate-of-rise relay (IOC) | Table B.1 | IEEE Std 3004.8-2016 |
| device function | dev50BF | 50BF | RBRF | — | Breaker failure protection | Table B.1 | IEEE Std 3004.8-2016 |
| device function | dev50G | 50G | — | — | Instantaneous overcurrent relay ground (zero-sequence CT) | Table B.1 | IEEE Std 3004.8-2016 |
| device function | dev50LR | 50LR | — | — | Instantaneous overcurrent locked-rotor relay (delayed on start) | Table B.1 | IEEE Std 3004.8-2016 |
| device function | dev51 | 51 | PTOC | — | AC time overcurrent relay (TOC inverse-time or definite-time) | Table B.1 | IEEE Std 3004.8-2016 |
| device function | dev51G | 51G | — | — | Time overcurrent ground relay | Table B.1 | IEEE Std 3004.8-2016 |
| device function | dev51N | 51N | — | — | Residually connected ground TOC relay | Table B.1 | IEEE Std 3004.8-2016 |
| device function | dev51R | 51R | — | — | Extreme overload protection for unloaded start of large synchronous motors (>=750 kW / 1000 hp); set just below pullout torque | Table B.1 | IEEE Std 3004.8-2016 |
| device function | dev51V | 51V | PVOC | — | TOC relay voltage restrained or voltage controlled | Table B.1 | IEEE Std 3004.8-2016 |
| device function | dev52 | 52 | XCBR | CB | Circuit breaker | Table B.1 | IEEE Std 3004.8-2016 |
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