Schneider Electric ComPacT NSX160N

Schneider Electric's **ComPacT NSX160N** is a high-performance Molded Case Circuit Breaker (MCCB), primarily used for overload protection, short-circuit protection, and isolation functions in low-voltage power distribution systems.

 I. Basic Parameters and Design

- **Frame Current**: 160A (adjustable range: 112-160A)

- **Breaking Capacity**: Class N (50kA), suitable for 380-415V AC systems; up to 90kA at 220V, and reduced to 10kA at 690V

- **Pole Number**: 3P or 4P (In the 4P model, the neutral wire (N) is located on the left; the 3D design indicates that the N wire is not involved in protection)

- **Rated Voltage**: 690V AC (50/60Hz), meeting the power distribution needs of most industrial and commercial applications

- **Trip Unit Type**: TMD (Thermomagnetic Trip Unit), providing overload (L) and short-circuit (I) protection, including:

  - Overload Protection (Ir): Adjustable range of 0.7-1×In (160A)

  - Short-Circuit Protection (Ii): Fixed value of 1250A (approximately 7.8 times the rated current)

 II. Structure and Installation

- **Installation Method**: Supports fixed, plug-in, and withdrawable mounting, enabling flexible adaptation to different cabinet designs

- **Overall Dimensions**:

  - 4P model: Width 140mm × Height 161mm × Depth 86mm, weight 2.6kg

  - 3P model: The width may be narrower (105mm according to some data), and confirmation is required based on the specific model

- **Connection Method**: Front connection design, with a terminal spacing of 35mm, supporting horizontal or vertical installation

III. Functions and Certifications

- **Protection Functions**:

  - Basic type: Provides long-time overload (L) and instantaneous short-circuit (I) protection, complying with the IEC 60947-2 standard

  - Optional expansion: Leakage protection, undervoltage tripping, remote control (e.g., MX/MN coils) can be realized by adding modules

- **Isolation Function**: Complies with the EN/IEC 60947-2 standard and can be used as an isolator

- **Environmental Adaptability**:

  - Operating temperature: -25°C to +70°C, humidity ≤95% (no condensation)

  - Certifications: CCC, EAC, Marine certifications, suitable for industrial, commercial, and marine environments

 IV. Application Scenarios

- **Power Distribution Systems**: Used as a main switch or branch switch to protect circuits for motors, lighting, and mixed loads

- **Industrial Control**: Cooperates with devices such as contactors and relays to build automatic control circuits

- **Renewable Energy**: Suitable for overcurrent protection in distributed generation systems such as solar energy and wind energy

V. Replacement and Upgrading

- **Replacement Models**: For higher breaking capacity, **NSX160H** (70kA) or **NSX160L** (100kA) can be selected

- **Digital Upgrading**: The new generation of ComPacT NSX series (e.g., NSX160N-D) supports the EcoStruxure Power architecture and can integrate functions such as wireless monitoring, energy metering, and service life prediction

 VI. Selection Recommendations

1. **Current Matching**: Calculate the rated current (In) based on the load, and ensure that the trip unit setting covers the normal operating current

2. **Breaking Capacity**: Select the breaking capacity class (N/H/L) according to the short-circuit current level at the installation location

3. **Accessory Expansion**:

   - Auxiliary Contact (OF): Used to indicate the status of the circuit breaker

   - Motorized Operating Mechanism (MT): Enables remote switching on and off

   - Leakage Module (Vigi NSX): Provides residual current protection

VII. Precautions

- **Installation Specifications**: Must comply with IEC 60947-2 and local electrical installation standards, and ensure that the terminal torque meets the requirements

- **Maintenance Recommendations**: Regularly inspect the contact wear condition; clean the arc-extinguishing chamber and test the tripping characteristics every 2-3 years