Description
The GE Multilin 750-P5-G5-D5-HI-A1-R-E-H is a high-performance feeder and motor management relay manufactured by GE Multilin (now GE Vernova Grid Solutions), purpose-built to deliver comprehensive protection, precision metering, disturbance recording, and asset monitoring for medium- and low-voltage distribution feeders and industrial motors. As a flagship member of the 750/760 Feeder Management Relay family, this fully loaded configuration consolidates phase overcurrent, directional overcurrent, ground fault, voltage protection, thermal modeling, and breaker control into a single drawout chassis — replacing an entire panel of discrete electromechanical relays with one intelligent electronic device.
Application Scenarios
Picture a coastal oil refinery where a critical 4160 V feeder supplies a bank of large induction motors driving crude-oil pumps. The salt-laden air has been quietly corroding standard control electronics for years, and the last thing the operations manager wants is a protection relay failing during a monsoon. The GE Multilin 750-P5-G5-D5-HI-A1-R-E-H is installed as the feeder protection IED, its “H” suffix conformal coating forming a verified barrier against moisture and chemical contaminants. When a phase-to-ground fault develops downstream, the relay’s directional overcurrent element (powered by the D5 polarized input) correctly determines the fault direction and isolates only the affected feeder — preventing a blind zone trip that would have taken down the entire pump bank. Meanwhile, the “E” enhanced LCD displays real-time thermal capacity and event records, giving operators immediate visibility into what happened and why.
Parameter
| Main Parameters | Value / Description |
|---|---|
| Product Model | GE Multilin 750-P5-G5-D5-HI-A1-R-E-H (also referenced as SR750) |
| Manufacturer | GE Multilin (GE Vernova Grid Solutions) |
| Product Category | Feeder & Motor Management Relay / Numerical Protection IED |
| Series / Platform | 750/760 Feeder Management Relay Series |
| Phase CT Input (P5) | 5 A nominal CT secondary; three-phase current measurement |
| Ground CT Input (G5) | 5 A nominal CT secondary; zero-sequence / ground current input |
| Polarized Input (D5) | 5 A polarized current input for directional overcurrent (67) element |
| Control Power (HI) | 90–300 VDC or 70–265 VAC, 48–62 Hz (high-range auxiliary supply) |
| Analog Output (A1) | 1 channel, 0–1 mA DC analog output (configurable as transducer/transmitter output) |
| Status LED (R) | Red LED indicating breaker closing status |
| Display (E) | Enhanced large-screen LCD with keypad; supports local setting and waveform viewing |
| Conformal Coating (H) | Harsh-environment PCB coating for chemical/corrosive/high-humidity installations |
| Protection Functions | Phase/gound overcurrent (50/51, 50N/51N), directional overcurrent (67), thermal overload (49), negative-sequence (46), undervoltage/overvoltage (27/59), underfrequency/overfrequency (81U/81O), breaker failure (50BF) |
| Metering | Voltage, current, kW, kVAR, kVA, kWh, kVARh, power factor, frequency, demand, energy |
| Harmonic Analysis | Up to 31st harmonic |
| Digital Inputs | 14 programmable logic inputs |
| Output Relays | 8 output relays (SPDT/Form-C contacts) |
| Communication Ports | Front RS232; rear RS485/RS422 (2 ports) |
| Communication Protocols | Modbus RTU, DNP 3.0 Level 2 (Ethernet requires “T” suffix) |
| Event Recording | 512 time-stamped events; sequence of events (SOE) |
| Disturbance Recording | Oscillography / waveform capture (COMTRADE format) |
| Configuration Software | EnerVista 750/760 Setup (offline setting files, COMTRADE viewer, SOE analysis) |
| Flash Memory | Field-upgradeable firmware via flash memory |
| Mounting | Drawout (withdrawal) case; panel or 19-inch rack mount |
| Dimensions (W × H × D) | 18 × 16.5 × 21.5 cm (approx.) |
| Weight | 6.5–7.9 kg (depending on configuration) |
| Operating Temperature | -40 °C to +60 °C |
| Storage Temperature | -50 °C to +90 °C |
| Relative Humidity | 5 % to 95 % RH, non-condensing |
| Front Panel Protection | IP40 (IP54 on some panel-mount variants) |
| EMI / RFI Immunity | IEC 61000-4 series compliant |
| Vibration Resistance | IEC 60255-21 compliant |
| Surge Withstand | ANSI/IEEE C37.90.1 compliant |
| Compliance | IEC 60255, ANSI/IEEE C37.90, IEEE C37.96, UL, CSA, CE |
| Lifecycle Status | Legacy / end-of-manufacture; supplied through new-surplus, refurbished, and repair channels |
