Arc Fault Circuit Interrupter 1P

AFDD-63 Arc Fault Circuit Interrupters (AFCI, also known as AFDD Arc Fault Detectors) technology is a new circuit protection product. Its primary function is to detect and differentiate dangerous ground arc faults, parallel arc faults, and series arc faults, and promptly activate devices to interrupt the current to prevent electrical fires. In the event of an arc fault, due to the relatively low current strength, which is below the set values of overcurrent protection widely installed in the power system, especially in the low-voltage distribution field, installing AFCI arc fault circuit interrupters at the distribution line terminals can promptly detect arcs and cut off the circuit, effectively reducing the losses caused by arcs.

The AFDD Fault Arc Disconnector is an intelligent circuit protector featuring an integrated MCB and RCCB design. It can detect and identify both fault arcs and normal arcs within the circuit. It prevents fire hazards caused by faulty arcs in electrical lines, such as poor contact and insulation issues. It combines fault arc protection, overload protection, short-circuit protection, overvoltage protection, surge suppression, and leakage protection into one unit.

Field and Application

AFCI fault arc circuit breakers and AFDD fault arc detectors are primarily installed in distribution boxes of terminal distribution systems. They can also be set up in homes, offices, various large supermarkets, department stores, airports, textile factories, warehouses, oil depots, refineries, hotels, and oil transportation pipelines, among other control points. The device can be installed and used wherever electricity is used, widely employed for electrical fire prevention.

Product Features

The AFDD Fault Arc Detector employs embedded system digital circuit control and an innovative arc characteristic recognition algorithm. Compact in size yet powerful in function, it achieves automatic monitoring and protection of fault arcs, effectively ensuring the safety of low-voltage power distribution lines, electrical equipment, and people.

Utilizing a comprehensive arc fault detection method that combines time-domain characteristic detection with frequency-domain FFT, simultaneous localization in both time and frequency domains is achieved.

◆Its specific features and functions are as follows:

(1) Equipped with automatic and manual control functions;

(2) Features the capability to detect and differentiate dangerous ground fault arcs, parallel arc faults, and series arc faults.

(3) Features and timely drives a device action to disconnect the current, preventing electrical fires.

(4) Features include overcurrent, short circuit, and overvoltage detection.

(5) Features fault memory function for easy fault inquiry and analysis.

(6) Features indicator light alarm

(7) Multi-rated current and voltage functionality

(8) Single-polarity rated make and break function

(9) Feature to display fault results

(10) Free Detachable Function

(11) Rustproof, moisture-resistant, and electric shock protection

Compared to systems composed of discrete component electrical devices, it features self-matching control and protection characteristics.

The AFDD Fault Arc Detector integrates control and protection functions, equivalent to an arc detection identifier plus a circuit breaker. It effectively resolves the matching issue between protection and control characteristics of discrete components, making the collaboration between protection and control characteristics more rational.

Arc detection and protection features compared to circuit breakers and fuses

Standard short-circuit protection devices based on circuit breakers and fuses can only provide equipment function protection in very small capacity power grids. However, due to the low current intensity during arc faults, which is below the current protection settings widely installed in the low-voltage distribution field of the current power system, these devices are unable to protect against arc faults.

◆ Features for detecting compared to arc detection devices with sensors

Due to the necessity of installing the AFDD fault arc detector sensor at the location where the fault arc occurs for detecting arc parameters, this poses an inconvenience for detecting fault arcs in power supply lines. However, the AFDD effectively resolves this issue.

◆ Features real-time operation compared to residual current devices (RCD)

During series and parallel arc faults, the fault impedance reduces the load current, causing it to fall below the RCD's trip value, which prevents the RCD from tripping quickly and in real time.

Product Advantages

● With built-in leakage protection, it enhances the reliability of electrical safety.
Technical improvements to electromagnetic mechanisms, including material and process enhancements and electronic circuit treatments, have avoided the previous issues of overheating and high temperatures during prolonged operation of electromagnets. This significantly reduces the working temperature of the electromagnets, thereby extending their lifespan.
● Suitable for various types of loads, with high stability.
● The fault interrupter circuit breaker has a rated working current as high as 63A.
● Designed with high-performance microcontrollers for the system, achieving digital control.
● Dedicated electromagnetic release mechanism, enhancing the accuracy of overcurrent protection.
● During an arc fault, the MCU internally makes multiple judgments, and only when all features match will it initiate the disconnection action.
● Wide application range, suitable for residents, enterprises, schools, and research institutions.
Integrated: Combines short-circuit protection, leakage protection, and arc protection into one
● Stability: Not affected by suppression load or EMI load shielding on its detection capability
● Multi-domain detection: Time domain, Frequency domain
Flexible installation methods: plug-in, bolted, and track-mounted installations.

Main Structure

Subject: The AFCI arc fault circuit interrupter is mainly composed of breaker modules, leakage modules, power modules, signal conditioning modules, detacher modules, and communication interface modules, etc.
Power Module: Supplies power to relevant components within the AFDD (Arc Fault Detection Device).
Signal Conditioning Module: The current signal in the main circuit is transmitted through a line current transformer to the signal conditioning module. The module amplifies, rectifies, and filters the signal before sending it to the microcontroller for processing.
◆ Detent Module: The electromagnetic structure of the detent module in AFCI arc fault circuit breakers employs a new energy-saving technology, reducing the core loss and short-circuit loss of the switching electromagnetic system, thereby saving electrical energy. A buffer device has been added to reduce the energy impact on the electromagnetic system, improving the switch's latching performance and extending its service life. The operating mechanism of the detent module can receive fault signals detected by the main control chip MCU, cutting off the coil circuit through control contacts, and breaking the main circuit by the electromagnetic mechanism. After fault rectification, the operation button is pressed to reset.
Communication Interface Module: This module enables real-time transmission of data such as current, voltage, current phase, and arc signals to the terminal computer, allowing for remote monitoring. The image below shows the current data information sent by the MCU to the host computer during a series arc occurrence. The Data Processing Module utilizes a self-developed AFDD arc fault detection host computer platform for data analysis and feature parameter extraction. A PC simulator is established to pre-simulate the algorithms on the PC, with the execution language compatible with microprocessors.

Operating Principle

The AFCI fault arc circuit breaker's main control chip MCU detects the current signal in the main circuit in real-time. Upon detecting a fault arc in the main circuit, the microcontroller sends a disengagement signal, and the disengagement circuit performs the disengagement operation.
Overload and other protections: The main control chip MCU of the AFCI fault arc circuit breaker also detects real-time faults such as overloads, leakage, under-voltage, over-voltage, and overcurrent in the main circuit, and sends fault signals to the release mechanism to disconnect the circuit, thereby achieving protective operation.