Hager NDN120 Miniature Circuit Breaker 1P 20A D-Curve 10kA AC

The Hager NDN120 is a high-performance single-pole miniature circuit breaker engineered to provide robust protection for electrical circuits in both residential and commercial environments. With a rated current of 20A and a D-type tripping characteristic, this device is specifically designed to handle high inrush currents, making it an essential component for maintaining safety and operational continuity in modern electrical installations.

Advantages

This circuit breaker offers exceptional reliability due to its 10kA breaking capacity, which ensures effective interruption of fault currents in demanding electrical systems. The D-curve characteristic provides a delayed response to short-term current surges, preventing nuisance tripping while maintaining high-level protection against sustained overloads and short circuits. Its compact single-pole design allows for efficient space utilization within distribution boards, and the high-quality construction ensures long-term durability and consistent performance under standard AC operating conditions.

Suitable for

• Protection of circuits with high inrush currents such as motors and transformers
• Residential electrical distribution boards
• Commercial building electrical systems
• Industrial control panels

This device may not be suitable for applications requiring B or C curve characteristics, where faster tripping times are necessary for standard lighting or general-purpose socket circuits. It is also not intended for use in DC systems, as it is specifically calibrated for AC electrical installations.

Key specifications

• Rated current: 20A
• Number of poles: 1
• Tripping characteristic: D-curve
• Breaking capacity: 10kA
• System type: AC

Installation should be performed by a qualified electrician in accordance with local electrical regulations. The device is designed for mounting onto a standard DIN rail within a distribution enclosure. Ensure that the supply voltage and frequency match the device specifications before connection. Securely tighten all terminal connections to the manufacturer's recommended torque settings to prevent overheating and ensure optimal electrical contact.

What to consider before purchase

• Verify that the D-curve characteristic is appropriate for your specific load type
• Ensure the 20A rating matches the requirements of your circuit wiring
• Confirm compatibility with your existing distribution board rail system
• Check that the 10kA breaking capacity meets the short-circuit current requirements of your installation site

Regular inspection of the circuit breaker is recommended to ensure that the mounting remains secure and that there are no signs of thermal damage or loose connections. Periodically test the installation to confirm that the protection system functions correctly within the intended parameters.