IK60N Circuit Breaker 3P+N 40A Curve C Curve C 6kA

The Schneider Electric Acti9 iK60N A9K24740 miniature circuit breaker is a modular automatic circuit breaker with 3 protected poles plus neutral, 40 A, C curve and 6 kA breaking capacity, designed to protect three-phase electrical circuits against overloads and short circuits. It operates at a rated voltage of 400 V AC and features a neutral pole switched simultaneously with the three phases, offering a compact solution for residential, commercial and tertiary distribution boards.

This reference belongs to Schneider Electric’s Acti9 iK60N range and complies with EN/IEC 60898-1. Its thermomagnetic protection, C curve, class 3 current limiting, DIN rail mounting and 6,000 A breaking capacity provide a reliable solution for low-voltage distribution circuits.

3P+N configuration with 3 protected poles

The Schneider Electric A9K24740 features a 3P+N configuration. This means the device has four physical poles, but overcurrent protection acts on the three phases.

• Total poles: 4.
• Protected poles: 3.
• Neutral: switched simultaneously.

When the miniature circuit breaker trips or is operated manually, the three phases and the neutral are disconnected together.

40 A rated current

The rated current of the A9K24740 is 40 A. This rating must be selected according to the design current of the circuit, conductor cross-section, installation method, ambient temperature and the characteristics of the connected loads.

The miniature circuit breaker must be sized so that it properly protects the wiring against overcurrents and its rated current is compatible with the expected installation conditions.

Thermomagnetic protection against overloads and short circuits

The Acti9 iK60N combines two tripping systems:

• Thermal protection: acts against sustained overloads that can cause excessive heating of the conductors.
• Magnetic protection: provides rapid operation against high short-circuit currents.

This combination allows a single device to protect the circuit against the main types of overcurrent.

C tripping curve

The A9K24740 reference incorporates a C curve, widely used in distribution circuits with loads that may present moderate inrush currents.

The magnetic tripping threshold for the C curve is approximately between 5 and 10 times the rated current.

This feature makes the miniature circuit breaker suitable, provided electrical calculations allow it, for circuits with:

• Lighting.
• Sockets and distribution lines.
• General-purpose electrical equipment.
• Small inductive loads.
• Compatible HVAC systems.
• Sub-distribution boards.
• Commercial and tertiary installations.

6 kA breaking capacity

Schneider Electric specifies for this miniature circuit breaker a rated breaking capacity Icn of 6,000 A at 400 V AC in accordance with EN/IEC 60898-1.

The device also has a service breaking capacity Ics of 6 kA, equal to 100% of the rated value under the conditions covered by the standard.

Before selecting the A9K24740, it must be verified that the prospective short-circuit current at the installation point does not exceed the device breaking capacity.

Class 3 current limiting

The Schneider Electric iK60N features class 3 current limiting in accordance with EN/IEC 60898-1.

During a short circuit, this limiting capability helps reduce the energy passing through the circuit before the breaker completes disconnection, decreasing thermal and electrodynamic stresses on conductors and other components.

400 V AC rated voltage

The main electrical characteristics of this reference include:

• Rated operational voltage Ue: 400 V AC.
• Frequency: 50/60 Hz.
• Rated current In: 40 A.
• Rated insulation voltage Ui: 440 V AC.
• Rated impulse withstand voltage Uimp: 4 kV.

These characteristics make it mainly suitable for low-voltage three-phase networks where a 3P+N configuration is appropriate.

Suitable for isolation

The A9K24740 is declared suitable for isolation in accordance with EN/IEC 60898-1.

This function allows the miniature circuit breaker to be used to isolate the circuit during maintenance operations within the corresponding safety procedures.

Lever operation

The device uses a front lever for manual switching on and off.

The position indicator makes it possible to visually identify whether the breaker is on or off.

DIN rail mounting

The Schneider Electric A9K24740 is designed for clip-on installation on a 35 mm DIN rail.

This system makes it easy to integrate with other modular devices inside electrical panels and allows quick, neat installation.

Double clip for easier removal

The Acti9 iK60N design incorporates a double clip that makes it easier to remove the device even when a comb busbar is installed.

This feature simplifies certain maintenance or replacement operations without the need to completely dismantle the panel’s modular distribution.

4-module format

The 3P+N configuration occupies a total width of 72 mm, equivalent to:

• 8 steps of 9 mm.
• 4 standard 18 mm modules.

Its approximate dimensions are:

• Width: 72 mm.
• Height: 85 mm.
• Depth: 78.5 mm.
• Weight: approximately 400 g.
• Color: white RAL 9003.

Terminals for conductors up to 35 mm²

For 40 to 63 A ratings in the iK60N range, Schneider Electric provides terminals designed for larger conductor cross-sections.

• Rigid conductor: 1 to 35 mm².
• Flexible conductor: up to 25 mm² depending on configuration.
• Tightening torque: approximately 3.5 Nm.

Conductor preparation and terminal tightening must be carried out according to the manufacturer’s instructions to avoid overheating and ensure a reliable connection.

IP20 protection rating

The miniature circuit breaker has an IP20 protection rating as a standalone device.

Once installed inside a suitable modular enclosure, Schneider Electric specifies protection up to IP40 for the assembly, depending on the enclosure and the installation performed.

High electrical and mechanical durability

The Acti9 iK60N is designed to withstand numerous operations throughout its service life:

• Mechanical durability: up to 20,000 cycles.
• Electrical durability: up to 10,000 cycles.

These features make it suitable for electrical panels subject to regular switching, disconnection and maintenance operations.

Wide temperature range

The Schneider Electric A9K24740 is designed to operate in:

• Operating ambient temperature: -25 to 60 °C.
• Storage temperature: -40 to 85 °C.

These characteristics make it suitable for installation in a wide variety of indoor electrical panels within the conditions specified by Schneider Electric.

Applications of the Schneider Electric A9K24740

The 40 A Acti9 iK60N miniature circuit breaker can be used in three-phase circuits with neutral where its rating, curve and breaking capacity are suitable.

Possible applications include:

• Three-phase residential electrical panels.
• Sub-distribution boards.
• Commercial premises.
• Office buildings.
• Tertiary installations.
• Main lines and compatible distribution circuits.
• Small workshops and professional installations.
• Loads with moderate inrush currents.

Does not include residual current protection

The A9K24740 is an MCB miniature circuit breaker. It protects against overloads and short circuits, but does not detect earth leakage currents.

When residual current protection is required, it must be used together with a suitable residual current device or another residual protection solution compatible with the characteristics of the circuit.

Technical characteristics of the Schneider Electric A9K24740

• Brand: Schneider Electric.
• Reference: A9K24740.
• Range: Acti9.
• Family: iK60.
• Model: iK60N.
• Type: MCB miniature circuit breaker.
• Application: electrical distribution.
• Configuration: 3P+N.
• Total number of poles: 4.
• Protected poles: 3.
• Neutral: simultaneous switching.
• Rated current In: 40 A.
• Tripping curve: C.
• Tripping technology: thermomagnetic.
• Magnetic threshold: 5-10 × In.
• Breaking capacity Icn: 6 kA at 400 V AC.
• Service breaking capacity Ics: 6 kA.
• Current limiting class: 3.
• Rated voltage Ue: 400 V AC.
• Frequency: 50/60 Hz.
• Insulation voltage Ui: 440 V AC.
• Rated impulse withstand voltage Uimp: 4 kV.
• Suitable for isolation: yes.
• Control: lever.
• Mounting: 35 mm DIN rail.
• Modular width: 4 x 18 mm modules.
• Width: 72 mm.
• Height: 85 mm.
• Depth: 78.5 mm.
• Weight: approximately 400 g.
• Color: white RAL 9003.
• Rigid conductor: 1-35 mm².
• Flexible conductor: up to 25 mm².
• Tightening torque: approximately 3.5 Nm.
• Protection rating: IP20.
• Protection in modular enclosure: up to IP40 depending on installation.
• Mechanical durability: up to 20,000 cycles.
• Electrical durability: up to 10,000 cycles.
• Operating temperature: -25 to 60 °C.
• Storage temperature: -40 to 85 °C.
• Standard: EN/IEC 60898-1.
• EAN: 3606480632204.

3P+N three-phase protection in just four modules

The Schneider Electric Acti9 iK60N A9K24740 combines three protected poles, switched neutral, 40 A rated current, C curve and 6 kA breaking capacity in a 72 mm modular format. Its configuration is especially practical for three-phase lines with neutral where all four active conductors need to be disconnected together.

Class 3 current limiting, DIN rail mounting, high durability and the double clip system complete a solution aimed at distribution boards where simple protection against overloads and short circuits is required.

Important: before installing the A9K24740, the design current, conductor cross-section, tripping curve, minimum and maximum short-circuit current and required breaking capacity must be checked. This device does not include residual current protection against earth leakage.