ABB REF620C_F NCFNAAAAABC2DNN1XF Feeder Protection and Control

ABB REF620C_F NCFNAAAAABC2DNN1XF Feeder Protection and Control

Basic characteristics of the device

The REF620C_F device is developed based on ABB's mature microcomputer protection platform and has four core characteristics: high reliability, strong adaptability, intelligence, and easy integration. In terms of reliability, the device adopts industrial grade high anti-interference components and redundant design, certified by international standards such as IEC 61850, and can operate stably in complex electromagnetic environments and a wide temperature and humidity range, with an average time between failures (MTBF) of over 100000 hours. In terms of adaptability, its protection logic and parameters can be flexibly configured, compatible with feeder circuits of different voltage levels (10kV/35kV) and wiring methods, meeting diverse distribution scenario requirements. Intelligence is manifested by the device's built-in powerful data processing unit, which supports fault recording, event recording, and status evaluation functions, and can provide early warning of potential equipment failures through data analysis. The easy integration feature is reflected in the device's support for multiple communication protocols such as IEC 61850 and Modbus, enabling seamless integration into intelligent distribution automation systems and achieving data sharing and remote control. In addition, the device adopts a modular hardware structure and a user-friendly interface, which facilitates installation, debugging, and operation and maintenance management.

Core Function Analysis

1. Comprehensive feeder fault protection

The device is equipped with a comprehensive protection function library, which can provide accurate and reliable protection solutions for common types of feeder faults. The core protection functions include: firstly, overcurrent protection, which is divided into timed overcurrent protection and inverse timed overcurrent protection. The action time can be automatically adjusted according to the magnitude of the fault current, quickly cutting off faults such as short circuits and overloads, and avoiding the expansion of faults; The second is grounding fault protection, which supports zero sequence current protection for low current grounding systems and zero sequence overcurrent protection for high current grounding systems. It can effectively detect single-phase grounding faults and reduce the impact of grounding faults on the power grid; The third is distance protection, which achieves selective disconnection of faults in different sections of the feeder by measuring the electrical distance between the fault point and the device, thereby improving the accuracy of protection; The fourth is overvoltage/undervoltage protection. When the grid voltage exceeds the set threshold, an alarm or trip action is triggered in a timely manner to protect the feeder and downstream equipment from abnormal voltage damage. At the same time, the device supports graded configuration of protection settings, which can be flexibly switched according to the operation mode of the power grid to adapt to different working conditions.

2. High precision operation monitoring and data acquisition

The device has high-precision electrical quantity acquisition function, which can monitor key operating parameters such as three-phase current, three-phase voltage, power factor, active power, reactive power, etc. of the feeder circuit in real time. The acquisition accuracy reaches 0.2 level, meeting the needs of energy metering and operation analysis. Through the built-in data processing module, the device can perform real-time analysis on the collected data, generate operation status reports, and provide comprehensive power grid operation information for operation and maintenance personnel. In addition, the device supports fault recording function. When a fault occurs, it can automatically record the current, voltage waveform and related electrical parameters before and after the fault. The recording data has high resolution and complete recording, providing important basis for fault cause analysis and responsibility determination. At the same time, the device can also monitor the operating status of itself and feeder equipment, such as switch position, device power status, communication status, etc., to achieve comprehensive perception of equipment status.

3. Flexible control and operation functions

The device supports remote and local control of feeder circuit switch equipment, achieving multiple operational functions: firstly, remote control operation, receiving control instructions from higher-level dispatch or automation systems through communication networks, completing switch opening and closing operations, supporting operation permission management and operation recording, ensuring operation safety; The second is on-site operation, which can be controlled by the operation buttons on the device panel or external operation handles to achieve local switch control, suitable for debugging or emergency situations; The third is the automatic control function, which supports linkage with the distribution automation system to achieve automatic fault isolation, load transfer, and other functions, enhancing the self-healing ability of the distribution network. For example, in the event of a fault in the distribution network, the device can cooperate with adjacent devices to isolate the fault area and restore power supply to the non fault area according to the instructions of the automation system, thereby shortening the power outage time. In addition, the device has anti misoperation function, which can make logical judgments on operating conditions and avoid power grid accidents caused by misoperation.

4. Efficient communication and networking capabilities

The device adopts advanced communication technology and has strong networking capabilities, supporting multiple communication interfaces and protocols: it is equipped with Ethernet interfaces, RS485 serial interfaces, etc. on the hardware, which can flexibly access different types of communication networks; The software supports the IEC 61850 standard communication protocol, achieving seamless integration with intelligent substations and distribution automation systems. It supports GOOSE (General Object Oriented Substation Event) messages and MMS (Manufacturing Message Specification) messages, enhancing the real-time and reliability of data transmission; Simultaneously compatible with industrial universal protocols such as Modbus RTU/TCP, making it easy to integrate with third-party devices or systems. Through the communication network, the device can achieve functions such as remote distribution of protection settings, uploading of operating data, and reporting of fault information, building an integrated distribution automation system of "monitoring control management", and improving the operation and maintenance efficiency of the distribution network.

5. Intelligent operation and diagnosis

The device is equipped with intelligent diagnosis and operation and maintenance functions, which can realize the status assessment and fault warning of itself and feeder equipment. Firstly, it has self diagnosis function, which monitors the internal circuit, components and software operation status of the device in real time. When hardware failure, software abnormality and other problems occur, the fault alarm is immediately triggered and the fault information is recorded, which is convenient for operation and maintenance personnel to quickly locate and handle; The second is equipment status assessment, which evaluates the health status of feeder switches, cables and other equipment through long-term monitoring and analysis of feeder operation data, combined with equipment aging models, and provides early warning of potential faults, providing a basis for equipment lifecycle management and preventive maintenance; The third is the operation and maintenance management function, which supports remote upgrading of device firmware, backup and recovery of protection settings, reduces on-site operation and maintenance workload, and improves operation and maintenance efficiency.

Key technical parameters

Applicable voltage level

Medium and low voltage distribution network, rated voltage 6kV~35kV

current input

Rated current 5A/1A (configurable), measurement range 0-20 times rated current

Voltage input

Rated voltage 100V (line voltage)/57.7V (phase voltage), measurement range 0-1.2 times rated voltage

measurement accuracy

Current and voltage: ± 0.2%; Power and electrical energy: ± 0.5%

Protection action time

Overcurrent protection: ≤ 20ms; Grounding protection: ≤ 30ms; Distance protection: ≤ 40ms

communication interface

2 10/100Mbps Ethernet ports (supporting IEC 61850), 1 RS485 interface (supporting Modbus RTU)

Switching input/output

16 switch inputs, 8 relay outputs (contact capacity AC 250V/5A, DC 24V/10A)

power supply

DC 24V/48V/110V/220V or AC 110V/220V, power consumption ≤ 25W

working environment

Temperature: -40 ℃~70 ℃; Humidity: 5%~95% (no condensation); Protection level: IP54 (device body)

Installation method

Embedded installation of switchgear and panel installation

Overall dimensions

240mm (length) × 180mm (width) × 120mm (height) (embedded installation size)

Applicable scenarios

The REF620C_F device is widely used in the field of medium and low voltage distribution due to its comprehensive protection function, accurate monitoring capability, and flexible networking characteristics. Typical scenarios include:

1. Industrial enterprise power distribution system: In the factory power distribution network of industrial enterprises such as steel, chemical, and automobile manufacturing, it is used to protect workshop feeders, power equipment supply circuits, etc., quickly cut off faults, avoid production interruptions caused by power outages, and help enterprises achieve energy management optimization through accurate energy metering and energy consumption monitoring.

2. Urban distribution network: In the overhead and cable feeder circuits of the 10kV distribution network in the city, the device can achieve fault protection and automation control of the feeder, cooperate with the distribution automation system to achieve automatic fault isolation and power supply recovery, improve the reliability of urban power supply, and reduce the power outage time for residents and commercial users.

3. Rail Transit Power Supply System: Used in the traction power supply system and power lighting power supply system of subway, light rail and other rail transit systems to protect feeder circuits, ensure stable power supply for traction equipment, lighting equipment, communication signal equipment, etc., and ensure the safe operation of rail transit.

4. Data center power distribution system: Data centers have extremely high requirements for power supply reliability, and devices can be used to protect data center UPS (uninterruptible power supply) feeders, server cabinet power supply circuits, etc. By quickly cutting off faults and accurately monitoring, the continuity and stability of data center power supply are ensured, avoiding data loss and business interruption caused by power supply failures.

5. New energy supporting distribution system: Used in the boosting stations and supporting distribution networks of photovoltaic power plants and wind farms to protect the new energy grid connected feeder circuits, achieve real-time monitoring and fault protection of grid connected current and voltage, ensure the safe grid connection and stable operation of the new energy power generation system, and enhance the new energy consumption capacity.

Precautions for use

-Before installing the device, it is necessary to check whether the model, specifications, and applicable scenarios match, whether the appearance of the device is damaged, and whether the internal components are loose; The installation location should be chosen in a dry and ventilated area, away from high temperature heat sources and strong electromagnetic interference sources, to ensure good heat dissipation of the device and facilitate operation and maintenance.

-Before wiring, it is necessary to disconnect the power supply of the device from the relevant primary equipment, strictly follow the wiring diagram for wiring, distinguish between current circuits, voltage circuits, control circuits, and communication circuits, and ensure that the wiring is firm and the polarity is correct; Open circuit is strictly prohibited in the current circuit, and short circuit is strictly prohibited in the voltage circuit to avoid device damage or protection misoperation caused by wiring errors.

-Before the device is put into operation, parameter configuration and functional testing should be carried out, and protection settings, alarm thresholds, and other parameters should be set according to the electrical parameters and protection requirements of the feeder circuit; Verify the correctness and reliability of the protection function through simulated fault tests, and ensure normal data exchange between the device and the higher-level system through communication testing.

-During the operation of the device, maintenance personnel need to regularly check the operating status, electrical parameters, and alarm information through the device panel or higher-level system, and regularly check the tightness and insulation of the wiring terminals; For fault waveform data and event records, regular export backups should be provided to provide a basis for fault analysis and system optimization.

-Device firmware upgrade requires obtaining genuine firmware through ABB official channels. Before upgrading, the current configuration parameters must be backed up, and power interruption is strictly prohibited during the upgrade process to avoid device failure caused by upgrade failure; If it is necessary to modify the protection setting, the operation process must be strictly followed and authorized before proceeding. After modification, verification testing must be conducted.

-When used in damp or dusty environments, it is necessary to strengthen the sealing and dust prevention measures of the device, and regularly clean the dust on the surface of the device and ventilation openings; In areas with frequent thunderstorms, it is necessary to equip the equipment and related distribution devices with a complete lightning protection grounding system to avoid damage to the equipment caused by lightning strikes.