Description

GE Multilin SR745-W2-P5-G5-HI-A

I. Overview

The GE Multilin SR745-W2-P5-G5-HI-A is a high-performance transformer protection relay in GE Multilin's 745 series. Designed to provide high-speed transformer management with built-in multi-processors, this model enables management and protection for dual-winding transformers. It has an extremely wide application range, covering numerous fields such as power, energy, and industrial manufacturing, playing a critical role in power systems of industries like metallurgy, petrochemicals, and machinery manufacturing. It provides solid support for the safe and stable operation of various large, medium, and small transformer systems.

II. Functional Features

Comprehensive and Precise Protection Functions

It offers a rich range of protection types, including but not limited to:

Overload Protection: Sensitive to long-term overloading of transformers and acts promptly.
Short-Circuit Protection: Quickly cuts off excessive current caused by short-circuit faults to prevent equipment damage.
Ground Fault Protection: Effectively detects ground abnormalities to avoid accident escalation.
Differential Protection: Accurately identifies internal transformer faults and distinguishes between normal operation and fault conditions.
Overheat Protection: Alerts and protects against excessive transformer temperatures from various causes, ensuring all-around safety.

Flexible Configuration Options

It allows flexible and precise configuration of relay protection parameters (such as operating current, action time, sensitivity, etc.) based on different transformer parameters (e.g., capacity, voltage level, winding connection mode) and actual application scenarios (e.g., system operation mode, load characteristics), achieving optimal protection effects.

Simple and Efficient Configuration Process

With a user-friendly configuration interface, operators can quickly and easily set various transformer parameters without complex professional knowledge or tedious operations, greatly improving work efficiency and reducing potential risks from configuration errors.

Excellent and Reliable Operation Performance

Using high-quality electronic components and advanced manufacturing processes, it ensures extremely high reliability and durability. It maintains stable operation in harsh environments with high loads, strong electromagnetic interference, and large temperature/humidity variations, reducing failure rates and maintenance costs.

Scientific Modular Design

This design simplifies installation and clarifies module 分工. During maintenance, faulty modules can be quickly located and replaced, significantly reducing downtime and improving system availability.

Diverse Communication Interfaces

Supporting common communication protocols like Modbus and IEC 61850, it enables seamless integration into various automation systems. Through these interfaces, remote data transmission, real-time monitoring, and control are achieved, facilitating remote management and analysis of transformer operation status by maintenance personnel.

III. Technical Parameters

Rated Phase Current: 5A, determining the transformer load current range the relay adapts to and ensuring accurate current signal monitoring/processing under normal and fault conditions.
Relay Voltage Input: 60 to 120V phase-neutral, adapting to voltage levels in different power systems for stable operation.
Ground Current Input Load: <0.025VA at 120V, reflecting the device's sensitivity to ground current detection and its impact on the system.
Frequency: Rated at 50 or 60Hz, compatible with power system frequency standards worldwide for broad applicability.
Operating Temperature: -40°F to +140°F (approx. -40°C to +60°C), enabling normal operation in extreme cold to high-temperature environments for diverse regional and application needs.
Control Power Supply: 90 to 300VDC or 70 to 265VAC (48 to 62Hz), offering multiple options to match different power supply systems and enhance application flexibility.
Display Type: 40-character LCD, clearly presenting transformer operation parameters, fault information, protection status, etc., for real-time key information acquisition by operators.
Transducer Output Channels: 7 channels, individually programmable for 4-20mA, 0-20mA, 1-10mA, and 0-1mA ranges, providing diverse analog signal outputs for external devices to meet different monitoring/control needs.

IV. Working Principle

The SR745-W2-P5-G5-HI-A real-time collects current and voltage signals from all transformer sides via built-in high-precision current transformers (CT) and voltage transformers (VT). These signals are transmitted to the internal multi-processor system, which performs high-speed calculations and analysis on the collected electrical quantities based on preset protection algorithms and logic.

Example: Differential Protection: The relay compares the magnitude and phase of currents on all transformer sides. During normal operation or external faults, the calculated differential current is near zero. When internal faults (e.g., winding short-circuits) occur, the current balance is broken, and the differential current exceeds the preset threshold, prompting the relay to rapidly issue a trip command, activating the corresponding circuit breaker to disconnect the transformer from the grid and protect it from further damage.
Overload Protection: The relay continuously monitors current. When the current exceeds the transformer's rated current by a certain multiple and persists for a certain time, it determines an overload. Based on the overload degree and preset inverse-time characteristic curves, it delays issuing alarm or trip commands to prevent insulation damage from overheating.

V. Operation Guide

Local Operation

Use the 40-character LCD and operation buttons on the device's front panel. Press the "Menu" button to enter the main menu, including options like "Settings," "Monitoring," and "Fault Records." In "Settings," further select submenus (e.g., "Transformer Parameters," "Protection Settings"), and follow screen prompts to modify parameters, view real-time data, and access fault records using direction keys and the "Enter" button. After operations, press "Exit" to return to upper menus or exit.

Remote Operation

If the device is connected to an automation system with normal communication, use host computer software. Open the monitoring software, select SR745-W2-P5-G5-HI-A in the device list, and enter the operation interface (similar to the local menu) for parameter configuration, real-time data monitoring, and remote control. When modifying parameters remotely, pay attention to operation authority management to ensure safety and accuracy. Save settings promptly and sync them to the device after operations.