Chint NM1LE-250S/4300A-160A 4-pole molded case residual current circuit breaker

Chint NM1LE-250S/4300A-160A is a 4-pole molded case residual current circuit breaker, mainly used in low-voltage power distribution systems to provide overload, short-circuit, residual current protection and line control functions.

I. Key Technical Parameters

1. Basic Specifications  

   - Frame Current: 250A (indicating the maximum continuous current that the circuit breaker frame can withstand).  

   - Rated Current: 160A (the current that can actually operate stably for a long time).  

   - Pole Number: 4P (three-phase four-wire, suitable for three-phase loads and single-phase loads with neutral lines).  

   - Breaking Capacity: 30kA (standard type, capable of interrupting a short-circuit current of 30kA).  

   - Residual Current Protection:  

     - Residual operating current is adjustable in three gears: 50/100/200mA, suitable for different safety requirements (e.g., 50mA for general places, and below 30mA can be used as supplementary protection against personal electric shock).  

     - Residual operating time ≤0.1 seconds, quickly cutting off the faulty circuit.  

2. Tripping Characteristics  

   - Thermomagnetic Release: It has both overload long-time delay (thermal protection) and short-circuit instantaneous (magnetic protection) functions with precise response.  

   - N Pole Characteristics: Type A design (N pole is straight-through without overcurrent protection), suitable for power distribution systems where the neutral line is not cut off.  

3. Certifications and Standards  

   - Complies with GB/T 14048.2 (Chinese standard) and IEC 60947-2 (international standard), and has passed CCC certification.  

II. Product Features and Applications

1. Core Functions  

   - Multi-level Protection: Integrates overload, short-circuit, and residual current protection to prevent electrical fires and personal electric shock.  

   - High Reliability: Mechanical life of 20,000 times and electrical life of 3,000 times, adapting to frequent operation requirements.  

   - Environmental Adaptability: Operating temperature range -5℃ to +40℃, altitude ≤2000 meters, suitable for industrial, commercial, and residential scenarios.  

2. Typical Application Scenarios  

   - Industrial Power Distribution: Main switch or branch protection for production lines and motor control centers.  

   - Commercial Buildings: Residual current protection for distribution boxes in office buildings and shopping malls.  

   - Residential and Infrastructure: Temporary electricity protection for community distribution rooms and construction elevators.  

III. Installation and Maintenance

1. Installation Methods  

   - Fixed Type: Fixed in the distribution cabinet through front-panel wiring, supporting vertical or horizontal installation.  

   - Accessory Expansion: Optional shunt release (remote control opening), auxiliary contacts (status feedback), etc. However, it should be noted that the N pole of Type A circuit breakers does not support some accessories.  

2. Precautions  

   - Wiring Specifications: Ensure that the incoming and outgoing line connections are firm to avoid overheating caused by looseness.  

   - Regular Testing: Press the "test button" monthly to check whether the residual current protection function is normal.  

   - Environmental Requirements: The installation site should be dry, free of corrosive gases, and avoid dust accumulation affecting performance.  

IV. Alternative Solutions and Market Status

1. Discontinuation and Alternatives  

   - Discontinued: This model is currently discontinued, with the order number 710301100004066. It is recommended to prioritize alternative models.  

   - Alternative Models:  

     - NXMLE Series (e.g., NXMLE-250S/4300A-160A): The breaking capacity is increased to 36kA, supporting residual current alarm without tripping function, suitable for more complex scenarios.  

     - NM1LE-G Series: There is still inventory in some channels, which can be used as a transitional option.  

2. Price Reference  

   - The market price before discontinuation was approximately 1021 yuan/unit. The price of the alternative NXMLE series is slightly higher (e.g., NXMLE-160H is about 2018 yuan/unit), and the specific price is subject to the dealer's quotation.  

V. Selection Suggestions

1. Current Matching: Select the rated current according to the total load current (e.g., 160A is suitable for loads ≤160A).  

2. Breaking Capacity: If the short-circuit current is high (e.g., in industrial environments), prioritize models with higher breaking capacity (e.g., NXMLE-H series with a breaking capacity of 50kA).  

3. Residual Current Sensitivity: For places involving personal safety, it is recommended to choose models with residual current ≤30mA; for general power distribution, 50-200mA is optional.  

4. Accessory Requirements: If remote control or status monitoring is needed, confirm in advance whether the circuit breaker supports the corresponding accessories.  

For more detailed technical data (such as installation dimension drawings, wiring diagrams), you can visit the official website of Chint Electric or contact local dealers.