GE 350-C-P5-G5-H-S-M-N-P-SN-D-N Feeder Protection System

The GE Multilin 350-C-P5-G5-H-S-M-N-P-SN-D-N, also cataloged as the 350 Feeder Protection System, operates as a dedicated hardware component for overcurrent tracking and directional fault isolation within electrical power distribution networks.

Hardware Specifications

Power Protection Matrix and Signal Execution

• Inverse Time Overcurrent Curve Calibration The firmware platform processes Phase, Neutral, Ground, and Negative Sequence (51P/51N/51G/51_2) profiles via mathematical inverse equations. It allows curve mapping through ANSI, IEC, IAC, and custom FlexCurve A/B tables with multiplier settings from 0.05 to 50.00 to guarantee accurate fault timing calculations matching downstream breakers.
• Quadrature Polarizing and Directional Logic For directional phase verification (67P), the circuit measures phase currents against quadrature voltage pairs based on the active phase sequence. The module evaluates tracking thresholds down to 0.05 x VT and references a programmable Maximum Torque Angle (MTA) from 0 to 359 degrees to isolate forward or reverse distribution line faults within 20 to 30 ms.

Frequently Asked Questions

Q: What are the primary timing distinctions between standard and sensitive ground elements during transient conditions?

A: Standard instantaneous overcurrent elements (50P/50N/50G/50_2) utilize a scaling matrix up to 20.00 x CT with operating dropouts set relative to 1 x CT thresholds. Sensitive Ground (50SG/51SG) subroutines scale tightly from 0.005 to 3.000 x CT, executing an adjusted dropout strategy based on 0.1 x CT levels to safely filter low-level leakage faults without nuisance trips.

Q: How is the security access hierarchy structured for local and remote modification?

A: The firmware enforces a split-tier password validation sequence. Basic parameter modification and control execution require a 3 to 10 character alphanumeric string valid across local HMI or remote engineering communication networks. Master clear sequences require a distinct 8 to 10 character security string.