GE 745-W3-P5-G5-HI-ALR-E-H Transformer Management Protection Relay

Product Description

GE 745‑W3‑P5‑G5‑HI‑ALR‑E‑H is a 3‑winding transformer management & protection relay from GE Multilin 745 series. OEM discontinued, it serves as critical protective spare part for legacy power substation systemsGE Vernova. The suffix W3 denotes support for three‑winding transformer protection. ALR includes analog I/O, transformer loss‑of‑life calculation and restricted ground fault functions. E stands for enhanced LCD display unit. H indicates conformal coating for high‑humidity and corrosive cabinet environments.

This all‑in‑one unit integrates main & backup protection, metering, oscillography, event logging and logic control. Protection functions include differential, over‑excitation, overcurrent, ground fault and on‑load tap changer control. Built‑in FlexLogic enables user‑defined complex interlock logic. Equipped with enhanced back‑lit LCD, keypad and multi‑LED status indicators. Communication ports include RS232, RS485 and Ethernet supporting Modbus and DNP3.0 protocols. Configuration, fault waveform retrieval and simulation test can be completed via EnerVista software. IRIG‑B time synchronization, fault waveform capture, event log and transformer ageing‑loss evaluation are supported. Draw‑out pluggable construction facilitates on‑site maintenance and replacement. Widely deployed for protection, maintenance and spare‑part swap of in‑service legacy power transformers.

2. Product Parameters

• Model: 745‑W3‑P5‑G5‑HI‑ALR‑E‑H
• Brand: GE Multilin (GE Vernova)
• Product Type: 3‑Winding Transformer Management & Protection Relay
• Series: 745 Transformer Protection System
• Transformer Compatibility: Three‑winding transformer (W3)
• Options: Analog I/O, Loss‑of‑Life calculation, Restricted Ground Fault, Enhanced Display, Conformal Coating (H)
• Control Power: 70‑265VAC / 90‑300VDC
• Current Input: 5A CT
• Digital Inputs: 16 logic inputs
• Relay Outputs: 8 output relays
• HMI: Enhanced back‑lit LCD, keypad, status LED indicators
• Communication: RS232, RS485, Ethernet; Modbus, DNP3.0 Level 2
• Time Synchronization: IRIG‑B
• Key Functions: Differential protection, over‑excitation protection, ground‑fault protection, FlexLogic custom logic, fault oscillography, event log, simulation test, transformer loss‑of‑life assessment
• Mounting: Panel‑mount draw‑out plug‑in unit
• Operating Temperature: ‑40℃ ~ +60℃
• Storage Temperature: ‑40℃ ~ +80℃
• Special Treatment: PCB conformal coating for corrosive & humid conditions
• Ingress Protection: IP20 (cabinet‑mount only)
• Product Status: OEM discontinued, power‑industry spare part; surplus new / used‑refurbished units available
• Weight: Approx. 4.8 kg
• Key Features: Complete 3‑winding protection, oscillography & event recording, user‑defined logic, multi‑protocol communication, conformal coating for harsh environment, draw‑out easy‑maintenance design

3. Product Application

The GE 745‑W3‑P5‑G5‑HI‑ALR‑E‑H protection relay is designed for main and backup protection of power transformers. Main application fields are listed below:

1. Substation Main Transformer Protection: Applied for three‑winding power transformers in substations, providing differential main protection, multiple backup protections for tripping and alarm.
2. Thermal & Hydropower Plants: Protection for station‑service transformers and main step‑up transformers; fault oscillography and event logging, interfaced with plant SCADA systems.
3. Combined‑Cycle Power Plants: Relay protection for generator step‑up and station‑service transformers, suitable for heavy EMI plant environments.
4. Petrochemical & Coal‑chemical Plants: Power transformer protection for on‑site substations; conformal coating adapts to corrosive, high‑humidity control‑room conditions.
5. Industrial Captive Power & Cogeneration Plants: Protection & measurement for three‑winding transformers in self‑generation facilities, standalone or integrated into automation systems.
6. Legacy Power‑system Maintenance & Retrofit: Fault‑module replacement for existing 745 installations; overhaul swap of legacy protective relays in substations and power plants to keep transformers safely operating.