For common faults and abnormal working conditions of transformers, multiple protection logics are built-in to ensure quick action in case of faults and minimize equipment damage:
-Overcurrent protection: including timed overcurrent and inverse time overcurrent protection, which can intelligently adjust the action time according to the degree of current abnormality, adapt to different fault scenarios, and effectively deal with problems such as short circuits and overloads.
-Differential protection: By comparing the current difference between the high and low voltage sides of the transformer, it accurately identifies internal short-circuit faults, has fast action speed and high sensitivity, and is the core protection method for internal faults in transformers.
Core function: Multi dimensional protection of transformer operation safety
This relay is centered around "precise protection and comprehensive monitoring" and has the following key functions, covering the full scenario requirements of transformer operation:
1. Comprehensive protection function
For common faults and abnormal working conditions of transformers, multiple protection logics are built-in to ensure quick action in case of faults and minimize equipment damage:
-Overcurrent protection: including timed overcurrent and inverse time overcurrent protection, which can intelligently adjust the action time according to the degree of current abnormality, adapt to different fault scenarios, and effectively deal with problems such as short circuits and overloads.
-Differential protection: By comparing the current difference between the high and low voltage sides of the transformer, it accurately identifies internal short-circuit faults, has fast action speed and high sensitivity, and is the core protection method for internal faults in transformers.
-Voltage protection: covering overvoltage, low voltage, and voltage imbalance protection, preventing insulation aging, iron core saturation, and other issues caused by abnormal voltage, ensuring equipment insulation performance.
-Temperature protection: Supports linkage with transformer oil temperature and winding temperature sensors to monitor temperature changes in real time. When the temperature exceeds the threshold, an alarm or trip is triggered to avoid overheating damage.
-Non electrical protection: It can be connected to non electrical signals such as gas relays and pressure relief valves to quickly respond to faults such as abnormal oil level and gas leakage in transformers, making up for the shortcomings of electrical protection.
2. Accurate measurement and monitoring
Adopting high-precision sensing and measurement technology, real-time collection of transformer operating parameters, providing comprehensive status data for operation and maintenance personnel:
-Electrical parameters: Accurately measure three-phase current, voltage, power factor, active power, reactive power, apparent power, and accumulated electrical energy on the high and low voltage sides, with a measurement accuracy of 0.2 level, meeting the measurement and monitoring needs of the power system.
-Temperature parameters: Supports the connection of multiple Pt100 platinum resistance temperature sensors, while monitoring the top oil temperature, bottom oil temperature, and winding hotspot temperature of the transformer. The temperature measurement range is -50 ℃~200 ℃, with an accuracy of ± 1 ℃.
-Status monitoring: Real time monitoring of the working status of the relay itself (such as power supply and module failures) and the status of transformer auxiliary equipment (such as cooling fans and oil pump operation), and timely feedback of abnormal information.
3. Flexible control and operation
Having rich control interfaces and operation modes, supporting local and remote control, and adapting to different operation and maintenance scenarios:
-Local operation: equipped with high-definition LCD display screen and buttons, supporting parameter setting, protection setting modification, manual opening and closing control, etc. The interface is simple and intuitive, and the operation logic is clear.
-Remote control: Receive backend system instructions through communication interfaces to achieve remote fixed value issuance, control command execution, data summoning, and other functions, supporting remote operation and maintenance of unmanned substations.
-Auxiliary control: It can automatically control the start and stop of the cooling system (such as fans and oil pumps) according to the operating status of the transformer, achieve temperature closed-loop control, and optimize equipment energy consumption.
4. Reliable communication and data exchange
Support multiple communication protocols and interfaces to ensure seamless integration with the backend monitoring system of the power system, achieving efficient data transmission and sharing:
-Communication Protocol: Compatible with mainstream power communication protocols such as IEC 61850, Modbus RTU/TCP, IEC 60870-5-103, and can flexibly adapt to monitoring systems from different manufacturers.
-Communication interface: equipped with 1 Ethernet interface (RJ45), 2 RS485 serial interfaces, supporting fiber optic communication module expansion, communication speed up to 100Mbps, stable and reliable data transmission.
-Data upload: Real time upload of measurement data, status information, fault recording data, etc., supporting SOE (sequence of events recording) of fault events, with a time resolution of 1ms, providing accurate basis for fault analysis.
Technical parameters: Hardware support for stable operation
The core technical parameters of this relay have been rigorously optimized to ensure stability and reliability in complex power environments. The key parameters are shown in the table below:
parameter category
specific parameters
Instructions
Power parameters
DC: 24V/48V/110V/220V; Communication: 110V/220V
Wide voltage input range, suitable for different power system power supply configurations
input current
Rated current: 5A or 1A
Support the connection of conventional current transformers, which can be adapted through parameter settings
input voltage
Rated voltage: 100V (line voltage)/57.7V (phase voltage)
Adapt to the secondary output of voltage transformers in high-voltage systems
Protection setting range
Overcurrent: 0.5~20Ie; Overvoltage: 1.05~1.5Un; Low Voltage: 0.5~0.95Un
Continuous adjustable constant value, suitable for different capacity transformer requirements
Action Time
Differential protection: ≤ 20ms; overcurrent protection: 0.01~30s
Quickly respond to faults and reduce their duration
working environment
Temperature: -25 ℃~70 ℃; Humidity: 5%~95% (no condensation); Altitude: ≤ 2000m
Adapt to complex outdoor environments such as high altitude and high temperature differences
mechanical properties
Anti vibration: 5-150Hz, acceleration 2g; anti impact: 10g (11ms)
Meet the mechanical environment requirements for power equipment transportation and on-site operation
Product advantage: Adapt to the upgrading needs of power systems
Compared to traditional transformer protection devices, GE SR745-W2-P1-G1-HI-A-L-R relay has significant advantages and is more in line with the intelligent and efficient operation and maintenance needs of modern power systems
1. Integrated design, simplifying system architecture: integrating multiple functions such as protection, measurement, monitoring, and communication, replacing traditional combination applications of multiple devices, reducing equipment footprint, lowering system wiring complexity, and improving operational reliability.
2. Coexistence of high precision and high reliability: Adopting GE patented signal processing algorithms and industrial grade hardware solutions, the measurement accuracy and protection action reliability have reached the international leading level. After rigorous electromagnetic compatibility testing (IEC 61000-4 series), it has strong anti-interference ability.
3. Intelligent operation and maintenance, reducing labor costs: supporting functions such as fault recording, event recording, and status diagnosis, it can automatically analyze equipment operation trends, warn potential faults in advance, reduce manual inspection frequency, and lower operation and maintenance costs.
4. Flexible expansion and adaptation to diverse needs: Reserve multiple expansion interfaces to increase the number of temperature sensor connections, communication module types, etc. according to actual needs, adapt to transformers of different capacities and application scenarios, and have good compatibility and scalability.
Application scenario: Covering the entire industry's electricity demand
With its comprehensive functionality and reliable performance, this relay is widely used in various power system scenarios, including:
-Power generation system: Main transformer protection for thermal power plants, hydropower plants, and new energy power stations to ensure stable connection between power generation equipment and the power grid.
-Power transmission and transformation system: protection of main and connecting transformers in 110kV~500kV substations to ensure the safe operation of the transmission network.
-Industrial enterprises: Protection of plant transformers for large industrial users such as steel, chemical, and metallurgical industries to avoid economic losses caused by power outages during production processes.
-Municipal facilities: protection of distribution transformers for urban rail transit, data centers, and high-rise buildings to ensure power supply for people's livelihoods and critical facilities.
Installation and maintenance: convenient and efficient full cycle support
This relay adopts standardized design, with a simple installation and maintenance process, reducing the difficulty of on-site construction and operation:
-Installation method: Supports both panel installation and rail installation, suitable for different cabinet structures. The wiring terminals adopt a plug-in design for easy on-site wiring and debugging.
-Maintenance guarantee: It has a complete self diagnostic function, which can monitor its hardware status in real time. When a fault occurs, the fault location is indicated through the alarm light and display screen, making it easy to quickly locate and repair; GE provides professional technical support and after-sales service to ensure stable operation of equipment throughout its entire lifecycle.




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