TX3 4P 20A Curve C Circuit Breaker 6kA

The Legrand TX³ 403627 miniature circuit breaker is a 4-pole, 20-amp automatic circuit breaker designed to protect electrical installations against overloads and short circuits. It features a C tripping curve, a rated voltage of 400 volts AC, and a breaking capacity of 6 kA at 400 volts.

Its four-pole configuration and modular format make it suitable for integration into residential and commercial distribution boards that require 4-pole circuit protection. It is installed on DIN rail, occupies 4 modules, and can be supplied from either the top or the bottom.

Legrand TX³ 4-pole 20-amp miniature circuit breaker

Reference 403627 belongs to the Legrand TX³ range of automatic circuit breakers. It incorporates 4 total poles and 4 protected poles, providing combined thermal-magnetic protection for the circuit conductors.

The device combines two protection systems. The thermal part acts against sustained overloads, while the magnetic trip responds quickly when a high short-circuit current occurs.

In addition to automatic protection, it can also be used for switching and isolating the installation, making it easier to disconnect the circuit during maintenance work.

C curve for circuits with moderate current surges

The Legrand 403627 features a C tripping curve. According to Legrand, magnetic tripping in the event of short circuits occurs between 5 and 10 times the rated current.

As this is a 20-amp miniature circuit breaker, the magnetic threshold is between 100 and 200 amps. This characteristic allows certain short-duration inrush currents to be tolerated without compromising fast response in the event of a short circuit.

Breaking capacity of 6 kA at 400 volts

The circuit breaker has a rated breaking capacity Icn of 6 kA at 400 volts according to EN 60898-1.

At 230 volts, the rated breaking capacity Icn reaches 10 kA. Breaking capacity indicates the maximum short-circuit current the device can interrupt under the conditions established by the standard and the manufacturer.

The model also has an energy limiting class 3, the level indicated by Legrand for this TX³ range of circuit breakers.

Protection against overloads and short circuits

When the current exceeds the permissible value of the circuit for a certain period, the thermal element causes the miniature circuit breaker to trip. In the event of a high-intensity short circuit, the magnetic mechanism provides a much faster response.

This combination helps protect cabling and connected equipment against the thermal and electrical effects associated with overcurrent.

DIN rail mounting in 4 modules

The Legrand TX³ miniature circuit breaker is designed to be installed on a DIN rail inside a distribution board. Its width corresponds to 4 modular spaces.

Its dimensions are approximately 70.8 mm wide, 88 mm high and 77.8 mm deep, with an installation depth of 44 mm.

This format makes it easy to install alongside residual current devices, contactors and other modular protection and control devices.

Top or bottom supply

The Legrand 403627 allows electrical supply from either the top or the bottom. It can be connected using copper cable or compatible distribution combs.

This provides greater flexibility in board design and wiring, especially when using busbar or comb distribution systems to supply several devices.

IP20 protected terminals

The connections feature IP20 protection against contact with live parts when the device is correctly installed. The terminals use screw connections and the range includes captive screws to make installation easier.

Connection capacity reaches up to 25 mm² with flexible conductor and up to 35 mm² with rigid conductor.

Label holder for circuit identification

The miniature circuit breaker includes a label holder that allows the protected circuit to be identified directly from the front of the distribution board.

This feature simplifies commissioning, inspection and maintenance tasks, especially in boards with numerous circuits and protection devices.

Compatible with Legrand DX³ auxiliaries

The Legrand TX³ 403627 supports the addition of compatible auxiliaries and accessories from the DX³ range. This means the installation can be expanded with certain control, signalling or actuation devices according to project requirements.

Technical characteristics of the Legrand 403627

• Brand: Legrand.
• Range: TX³.
• Reference: 403627.
• EAN: 3245064036276.
• Product type: miniature circuit breaker.
• Number of poles: 4.
• Number of protected poles: 4.
• Rated current: 20 amps.
• Tripping curve: C.
• Magnetic trip threshold: between 100 and 200 amps.
• Rated voltage: 400 volts.
• Rated voltage range: between 360 and 440 volts.
• Voltage type: AC.
• Frequency: between 50 and 60 Hz.
• Breaking capacity Icn at 400 volts according to EN 60898-1: 6 kA.
• Breaking capacity Icn at 230 volts according to EN 60898-1: 10 kA.
• Breaking capacity Icu at 400 volts according to IEC 60947-2: 6 kA.
• Breaking capacity Icu at 230 volts according to IEC 60947-2: 10 kA.
• Rated insulation voltage: 500 volts.
• Impulse withstand voltage: 4 kV.
• Energy limiting class: 3.
• Number of modules: 4.
• Mounting type: DIN rail.
• Installation depth: 44 mm.
• Width: 70.8 mm.
• Height: 88 mm.
• Depth: 77.8 mm.
• Degree of protection: IP20.
• Impact resistance: IK02.
• Pollution degree: 2.
• Maximum flexible conductor cross-section: 25 mm².
• Maximum rigid conductor cross-section: 35 mm².
• Connection: screw terminal, cable or distribution comb.
• Supply direction: top or bottom.
• Storage temperature: between -40 and 70 °C.
• Color: RAL 7035 grey.
• Halogen-free: yes.
• Label holder: included.
• Compatible with auxiliaries: yes.

Four-pole protection for electrical distribution boards

The Legrand TX³ 403627 miniature circuit breaker combines a rated current of 20 amps, C curve, 4-pole protection and a breaking capacity of 6 kA at 400 volts in a compact 4-module format.

Its DIN rail mounting, top or bottom supply option, protected terminals, label holder and compatibility with DX³ accessories make it easy to integrate into electrical distribution boards that require reliable protection against overloads and short circuits.