Chint NB2LE C20 circuit breaker

The Chint NB2LE C20 circuit breaker is a miniature residual current circuit breaker (RCCB) with residual current protection, overload protection, and short-circuit protection. The following introduces it in terms of specification parameters, working principles, application scenarios, etc.:  

Specification Parameters  

- **Rated Current**: 20A. This is the current value at which the circuit breaker can operate stably for a long time, suitable for circuits where the load current does not exceed 20A.  

- **Tripping Characteristics**: C-type tripping curve, generally used to protect distribution lines and electrical equipment with high inrush currents. Usually, when the current reaches 5-10 times the rated current, the circuit breaker will quickly trip to protect the circuit safety.  

- **Pole Number**: 1P+N, where 1P is used to control the live wire, and N is used to connect the neutral wire. It can cut off the live wire only when faults such as leakage, overload, or short circuit occur, while the neutral wire remains connected, reducing the risk of electric shock and equipment damage caused by neutral wire disconnection.  

- **Rated Residual Operating Current**: Typically 30mA. When the residual current in the circuit reaches or exceeds this value, the circuit breaker will automatically cut off the circuit in an extremely short time to prevent accidents such as electric shock and electrical fires.  

- **Rated Voltage**: Suitable for circuits with alternating current 50/60Hz and rated voltage 230V/240V.  

- **Breaking Capacity**: Generally 6kA, meaning that the circuit breaker can reliably break the maximum short-circuit current of 6kA at the rated voltage, with strong short-circuit protection capability.  

 Working Principles  

- **Residual Current Protection**: By detecting the vector sum of the currents in the live wire and neutral wire. Under normal conditions, the currents in the live wire and neutral wire are equal in magnitude and opposite in direction, with a vector sum of zero. When leakage occurs, part of the current flows into the ground through the human body or other leakage paths, causing the vector sum of the currents in the live wire and neutral wire to be non-zero. When this residual current reaches the rated residual operating current, the leakage tripper acts, making the circuit breaker trip and cut off the circuit.  

- **Overload Protection**: Using the thermal effect principle of a bimetallic strip. When an overload current occurs in the circuit, the bimetallic strip bends due to heating. After a certain period, the bending degree is sufficient to push the tripping mechanism to act, making the circuit breaker trip, thereby protecting the circuit and equipment from overload current damage.  

- **Short-Circuit Protection**: When a short circuit occurs in the circuit, the short-circuit current increases instantaneously. The electromagnetic tripper of the circuit breaker will quickly act under the strong electromagnetic force generated by the short-circuit current, pushing the tripping mechanism to make the circuit breaker trip, quickly cutting off the short-circuit current and preventing serious damage to the circuit and equipment.  

 Application Scenarios  

- **Household Residences**: It can be used in the main distribution box or the distribution boxes of each room in the home as a line protection switch. It can protect various household electrical appliances such as air conditioners, refrigerators, washing machines, and electric water heaters from overload, short circuit, and leakage, preventing safety accidents caused by electrical failures and ensuring the personal safety of family members and the normal operation of household electrical equipment.  

- **Small Commercial Places**: Such as small stores, barber shops, offices, etc. The electrical equipment in these places is relatively small, but reliable electrical protection is also required. The Chint NB2LE C20 circuit breaker can provide effective protection for the distribution lines of these places, ensure safe power use, and avoid affecting normal business operations due to electrical failures.  

- **Industrial Control Circuits**: In some small industrial equipment or production lines, it is used in circuits controlling electrical equipment such as motors and contactors, which can prevent overload, short circuit, and leakage caused by equipment failures or line problems, protect the safe operation of industrial equipment, and reduce production accidents and economic losses caused by electrical failures.  

 Installation and Maintenance  

- **Installation**: During installation, operations should be carried out strictly in accordance with the requirements of the product manual to ensure that the circuit breaker is firmly installed and the wiring is correct. It should generally be installed in a dry, well-ventilated, and convenient position for operation and maintenance, and the altitude and ambient temperature of the installation position should comply with the range specified in the product.  

- **Maintenance**: Regularly inspect the circuit breaker, check whether the appearance of the circuit breaker is damaged or deformed, whether the wiring terminals are loose, and whether the operation handle is flexible. At the same time, leakage tests can be carried out regularly to ensure the normal operation of the leakage protection function. If the circuit breaker is found to be faulty or abnormal, it should be replaced or repaired in a timely manner to avoid losing the protection function due to circuit breaker failure.  

The Chint NB2LE C20 circuit breaker is suitable for the following scenarios:  

- **Household Residences**: It can be used in the main distribution box of the home or the distribution boxes of each room as a line protection switch. It can protect various household electrical appliances such as refrigerators, TVs, washing machines, and electric water heaters from overload, short circuit, and leakage, prevent fires and electric shock accidents caused by electrical failures, and ensure the personal safety of family members and the normal operation of household electrical equipment.  

- **Small Commercial Places**: Such as small stores, barber shops, clinics, offices, etc. The power load of these places is relatively small, and the Chint NB2LE C20 circuit breaker can provide reliable protection for their distribution lines. It can quickly cut off the circuit when overload, short circuit, or leakage faults occur, avoid affecting the normal progress of commercial activities due to electrical accidents, and protect the safety of personnel and equipment in the场所.  

- **Industrial Auxiliary Circuits**: In some industrial production environments, the Chint NB2LE C20 circuit breaker can also play a role in small auxiliary equipment or local lighting and control circuits. For example, small ventilation equipment, electric tools, local lighting lines, etc. in the factory workshop, whose rated current does not exceed 20A. Using this circuit breaker can effectively protect these circuits and prevent production interruptions or equipment damage caused by electrical failures.  

- **High-Rise Buildings**: In high-rise residences or office buildings and other buildings, in addition to being used as the terminal protection switch for families or small offices, it can also be used for the protection of lighting, sockets, and other circuits in some public areas, such as corridor lighting, part of the auxiliary circuits in the elevator machine room, etc., to ensure the safe power use of these areas and maintain the stable operation of the entire building's electrical system.