With the rapid development of renewable energy, electric vehicles, and energy storage systems, direct current (DC) power systems have been widely applied in various fields. As a core protective component in the power system, circuit breakers are divided into AC and DC types according to the current form. Many people will have questions: are AC and DC circuit breakers interchangeable? The answer is definitely no. There are essential differences between them, especially in arc extinguishing performance.Dc Circuit Breaker has become a key component to ensure the safe operation of DC power systems. Zhejiang C&J Electrical co., ltd. (referred to as C&J Electrical) has launched the CJMD16-63 series DC MCB, which provides reliable protection for DC power systems.
Core Difference: AC vs. DC Circuit Breakers
A very important difference when interrupting alternating current and direct current is that the arc extinguishing point is higher for a DC circuit breaker. In direct current where voltage is continuous, the electric arc is constant and more resistant to interruption. This is the most fundamental difference between the two. Specifically, alternating current has a natural zero-crossing point (the current value becomes zero 100 times per second in a 50Hz power grid), and the electric arc will naturally extinguish when it crosses zero, making arc extinguishing relatively easy. However, direct current has no zero-crossing point; the voltage and current are continuous and stable, so the electric arc generated when the circuit is disconnected is more persistent and has higher energy, which requires a more advanced arc extinguishing system for the Dc Circuit Breaker.
In addition to the core difference in arc extinguishing, AC and DC circuit breakers also differ in voltage withstand level, current-carrying capacity, and structural design. Therefore, they cannot be used interchangeably. Using an AC circuit breaker in a DC system will lead to failure to extinguish the arc, equipment burnout, or even fire accidents.
What is a DC Circuit Breaker?
A Dc Circuit Breaker is a specialized protective electrical component designed for DC power systems. Its core function is to cut off the DC circuit quickly and reliably when faults such as overload, short circuit, or overvoltage occur in the DC system, preventing the fault from expanding and protecting the safety of electrical equipment and the power system. Compared with AC circuit breakers, Dc Circuit Breaker has a more complex and efficient arc extinguishing structure, which can quickly suppress and extinguish the persistent DC arc.
With the continuous expansion of DC application scenarios (such as photovoltaic power generation, energy storage systems, electric vehicle charging piles, etc.), the performance requirements forDc Circuit Breaker are getting higher and higher. It not only needs to have excellent arc extinguishing performance but also needs to adapt to the characteristics of high voltage and large current in DC systems.
Core Functions of DC Circuit Breaker
As a core protective component in DC power systems, Dc Circuit Breaker integrates multiple protection functions to form a comprehensive safety defense line:
- Short circuit protection: Quickly cut off the circuit when a short circuit fault occurs in the DC system, suppressing the rapid rise of short circuit current and avoiding damage to equipment
- Overload protection: Monitor the load current in real time; when the current exceeds the rated value for a long time, trip the circuit to prevent overheating of wires and equipment
- Arc extinguishing protection: Through a professional arc extinguishing system, quickly extinguish the persistent DC arc generated when the circuit is disconnected, ensuring safe breaking
- Fault indication: Provide clear fault status indication to help maintenance personnel quickly locate and eliminate faults
- Isolation function: After tripping, it can reliably isolate the faulty part from the power system, ensuring the safety of maintenance operations
C&J Electrical’s CJMD16-63 DC MCB: Core Advantages & Technical Specifications
C&J Electrical’s CJMD16-63 series DC MCB is a high-performanceDc Circuit Breaker, which adopts advanced design and excellent materials to provide reliable protection for DC power systems. Its core structure, functions, and technical parameters are as follows:
Core Structure & Functional Advantages
- Advanced design & comfortable operation: Elegant appearance, curved cover plate and handle for comfortable operation; with contact position indication window and transparent cover plate for label pasting
- Handle centering function: Used for circuit fault indication; when overloaded, the MCB handle trips and stays in the centering position to quickly locate faults (cannot stay in this position during manual operation)
- High short-circuit capacity: Thanks to the powerful arc extinguishing system, the short-circuit capacity of the whole series reaches up to 10kA, and up to 15kA when the rated current is up to 40A; the quick closing mechanism ensures an electrical life of up to 6000 cycles
- Handle locking device: The MCB handle can be locked in the “on” or “off” position to prevent accidental startup of the product
- Screw terminal locking device: Prevents accidental or arbitrary disassembly of connection terminals, ensuring connection reliability
Inner Structure
Key Technical Parameters
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Parameter
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Details
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Standard
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IEC60947-2
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Pole configuration
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1P, 2P, 3P, 4P
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Rated voltage
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1P: 250V; 2P: 500V; 3P: 800V; 4P: 1000V
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Rated current (A)
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1, 2, 3, 4, 6, 10, 13, 16, 20, 25, 32, 40, 50, 63
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Trip curve
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B, C
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Rated short-circuit breaking capacity
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10kA
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Rated impulse withstand voltage
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6.2kV
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Electromechanical durability
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10000 cycles
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Screw terminal
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M5
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Rated torque
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2.0N·m
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Installation method
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35mm rail mounting
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Versatile Application Scenarios of CJMD16-63 DC MCB
With excellent performance and wide adaptability, the CJMD16-63 series Dc Circuit Breaker is widely used in various DC power system scenarios, including:
- Renewable energy systems: Photovoltaic power generation systems, wind power generation DC link protection
- Energy storage systems: Lithium-ion battery energy storage cabinets, flow battery energy storage systems
- Electric vehicle industry: Electric vehicle charging piles, on-board DC power system protection
- Industrial equipment: DC power supply systems for industrial automation equipment, DC motor control circuits
- Commercial & residential fields: DC power systems for smart buildings, solar water heater systems, UPS power supply systems
- Communication systems: DC power supply protection for communication base stations, data center UPS systems
Why Choose C&J Electrical’s CJMD16-63 DC MCB?
In the field of Dc Circuit Breaker, the CJMD16-63 series from C&J Electrical has obvious competitive advantages:
- Excellent arc extinguishing performance: Equipped with a powerful arc extinguishing system, which can reliably extinguish DC arcs and ensure safe breaking
- High reliability: High short-circuit capacity and long electromechanical durability, adapting to long-term stable operation in complex DC environments
- User-friendly design: With fault indication, handle locking, and terminal locking functions, it is safe and convenient to operate and maintain
- Wide adaptability: Multiple pole configurations, rated voltage, and current levels are available to meet the needs of different DC systems
- International standard compliance: Meets IEC60947-2 standard, ensuring product quality and safety performance
Get in Touch
If you have any questions about the CJMD16-63 series Dc Circuit Breaker, such as product specifications, technical details, customization needs, or bulk orders, please feel free to contact C&J Electrical. Our professional team will provide you with tailored DC power system protection solutions to ensure the safe and stable operation of your equipment and system.
Post time: Dec-26-2025