DX3 4P 16A Circuit Breaker Curve C 6/10kA

The Legrand DX³ 407928 thermal magnetic circuit breaker is a four-pole automatic circuit breaker designed to protect electrical installations against overloads and short circuits. It has a rated current of 16 amps, a rated voltage of 400 volts AC, and a Type C tripping curve.

Its 4 protected poles configuration allows the conductors of the circuit to be disconnected together, making it especially suitable for integration into electrical panels and three-phase distribution systems where four-pole protection is required.

Breaking capacity of 6 and 10 kiloamps

The Legrand 407928 offers a rated breaking capacity of 6 kiloamps at 400 volts according to EN 60898-1, used for circuit breakers intended mainly for domestic installations and similar applications.

According to IEC 60947-2, the device also has an ultimate breaking capacity of 10 kiloamps at 400 volts. At 230 volts, the ultimate breaking capacity reaches 25 kiloamps.

This capacity allows the thermal magnetic circuit breaker to safely interrupt high short-circuit currents within its rated values, helping protect both the wiring and the equipment connected to the installation.

Type C curve for electrical circuit protection

The Type C tripping curve provides instantaneous magnetic tripping when the current reaches approximately between 5 and 10 times the rated current.

In this 16-amp model, the magnetic tripping threshold against short circuits is approximately between 80 and 160 amps. This feature allows it to withstand certain short-duration current surges without causing unnecessary trips, while still maintaining protection against high overcurrents.

Protection against overloads and short circuits

The DX³ automatic circuit breaker combines thermal protection, designed to act against prolonged overloads, with magnetic protection, which responds quickly to short-circuit currents.

In addition to protecting the installation, the thermal magnetic breaker can be used for control, switching and circuit isolation functions, making maintenance and switching operations easier inside the electrical panel.

Four-pole 4-module format

The Legrand DX³ 407928 has 4 total poles and 4 protected poles. Its width corresponds to 4 modular spaces, allowing it to be neatly integrated alongside other protection, control and signaling devices.

It is designed for mounting on DIN rail and has an installation depth of 44 millimeters. Power supply can be connected from either the top or the bottom, providing greater flexibility during panel wiring.

Compatible with Legrand DX³ combs and auxiliaries

The thermal magnetic breaker can be connected using copper conductors and is compatible with different Legrand distribution comb systems, facilitating the shared supply of several modular devices within the electrical panel.

The DX³ range also allows the incorporation of certain control and signaling auxiliaries, residual current blocks and other compatible accessories, making it possible to expand the protection and control functions of the installation when the project requires it.

Terminals for rigid and flexible conductors

The connection terminals accept flexible conductors with cross-sections between 1.5 and 25 square millimeters and rigid conductors between 1.5 and 35 square millimeters.

The system uses screw terminals and has an IP20 protection rating, helping reduce the risk of accidental contact with live parts when the product is correctly installed.

Easy identification inside the panel

The circuit breaker includes a label holder that makes it easier to identify the protected circuit. This feature is especially useful in panels with multiple lines, as it allows quick recognition of each thermal magnetic breaker during maintenance or intervention tasks.

The connection and disconnection position is also clearly indicated on the operating lever, making it easier to visually check the device status.

Technical characteristics of the Legrand 407928

• Brand: Legrand.
• Range: DX³.
• Reference: 407928.
• EAN: 3245064079280.
• Product type: thermal magnetic circuit breaker.
• Number of poles: 4.
• Number of protected poles: 4.
• Rated current: 16 amps.
• Rated voltage: 400 volts.
• Voltage type: alternating current.
• Tripping curve: C.
• Magnetic threshold: between 5 and 10 times the rated current.
• Breaking capacity according to EN 60898-1 at 400 volts: 6 kiloamps.
• Ultimate breaking capacity according to IEC 60947-2 at 400 volts: 10 kiloamps.
• Ultimate breaking capacity according to IEC 60947-2 at 230 volts: 25 kiloamps.
• Rated insulation voltage: 500 volts.
• Impulse withstand voltage: 4 kilovolts.
• Frequency: between 50 and 60 hertz.
• Energy limiting class: 3.
• Number of modules: 4.
• Mounting type: DIN rail.
• Installation depth: 44 millimeters.
• Width: 70.8 millimeters.
• Height: 94.8 millimeters.
• Total depth: 77.8 millimeters.
• Protection rating: IP20.
• Impact resistance: IK02.
• Pollution degree: 2.
• Operating ambient temperature: between -25 and 70 degrees Celsius.
• Storage temperature: between -40 and 70 degrees Celsius.
• Flexible conductor cross-section: between 1.5 and 25 square millimeters.
• Rigid conductor cross-section: between 1.5 and 35 square millimeters.
• Connection method: screw terminal.
• Supply direction: from the top or bottom.
• Color: gray.

DX³ thermal magnetic breaker for three-phase electrical panels

Thanks to its 4-pole configuration, 16-amp rated current, Type C curve and breaking capacity of up to 10 kiloamps at 400 volts according to IEC 60947-2, the Legrand DX³ 407928 offers a complete solution for protecting electrical circuits against overcurrents.

Its modular format, DIN rail mounting, top or bottom supply option, compatibility with DX³ accessories and wide conductor connection range make it easy to incorporate into both new electrical panels and expansion or renovation work on existing installations.