Circuit breakers for reliable, compliant protection

Electrical Power & Protection

October 2025 Electrical Power & Protection

Legrand’s low-voltage power distribution portfolio encompasses the DX₃ range of miniature circuit breakers, designed to deliver dependable protection in industrial installations. The range covers ratings from 1 A to 125 A, with breaking capacities up to 50 kA, making this system suitable for installations where performance and safety compliance are essential.

The DX₃ range provides a wide selection of tripping curves − from B and C types for resistive and general-purpose loads, to D and Z types for inductive or sensitive equipment. This flexibility allows installers and designers to match breaker characteristics precisely to system requirements, improving selectivity and operational reliability. These devices combine thermal and magnetic trip mechanisms. The thermal element ensures reliable response to prolonged overloads, while the magnetic element provides instantaneous disconnection in the event of a short circuit.

As electrical installations advance to include more sensitive equipment and higher energy densities, it is increasingly important that protection devices meet stringent standards, and are easy to specify and install. DX₃ circuit breakers are engineered to handle high fault levels safely and to perform consistently in both AC and DC systems. This range, with rated operational voltages up to 230/400 V AC and dedicated DC configurations for solar and battery applications, offers safety compliance and long-term reliability.

Installers value many features of the DX₃ range, including those that enhance safe operation. Wide connection reinforced terminals with compensating clamps reduce the risk of overheating from loose connections, and retractable insulating shields are designed to prevent accidental contact. Clear contact position indicators, secure label holders and full compatibility with auxiliaries allow quick installation and uncomplicated integration into distribution boards and energy management systems. Typical applications are in data centres, commercial buildings and renewable energy systems.

The DX₃ range is also classified for high current-limiting performance. By interrupting fault currents before they reach their peak value, these breakers significantly reduce the thermal and mechanical stresses imposed on conductors and connected equipment. This critical feature not only protects downstream devices, but also extends the service life of the overall installation.

DX₃ circuit breakers are compliant with IEC 60898-1 and IEC 60947-2 specifications, and are suitable for use in environments from residential distribution boards to industrial panels requiring higher short-circuit capacities. These devices have insulation voltages up to 500 V and are tested to stringent endurance requirements, ensuring reliable performance throughout their service life.

Legrand’s DX₃ circuit breakers are available in single- to four-pole versions, and can be installed in both alternating and direct current systems. The design also facilitates multipole series connection for higher DC voltages, which is an important consideration in photovoltaic and battery storage applications.

By combining robust electrical performance with advanced technology and practical design features, the DX3 range ensures safer, more efficient power distribution in diverse installations.

For more information contact Legrand SA, +27 11 444 7971, legrand.south-africa@legrand.co.za, www.legrand.co.za

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Electrical Power & Protection

Circuit breakers for reliable, compliant protection

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