GE Multilin 750/760 Feeder Protection System Digital Relay Applications

Applications

- Primary protection and control of distribution feeders for solidly grounded,

high impedance grounded or resonant (Peterson coil) grounded systems

- Busbar blocking/interlocking schemes

- High-speed fault detection for arc-flash mitigation

- Load shedding schemes (bus transfer scheme applications)

- Load shedding schemes based on voltage and frequency elements

- Backup protection for transmission lines, feeders and transformers

- Distributed generation (DG) interconnection protection

Protection and Control

The 750/760 Feeder Protection System is a digital relay for the management, primary protection and control of distribution feeders.

This easy-to-use relay provides comprehensive protection functions for feeders and backup protection for buses,

transformers and transmission lines while reducing product life cycle costs.

Time and Instantaneous Overcurrent

The 750/760 has a two-phase TOC element with level detectors for each phase.

750/760 also has two overcurrent elements, most commonly used for primary and backup protection.

Each TOC element has the following programmable features:

- Pickup current levels for tripping, alarming, or control

- Choice of 15 curve shapes (including FlexCurves) and curve multipliers

- Instantaneous or linear reset time characteristics

- Voltage limiting

The 750/760 has two phase IOC elements, each with a level detector.

Each IOC element has a programmable pickup current, a time delay after which the current

must exceed the pickup current to operate, and a minimum number of phases required to operate.