C120N 4P 80A Curve D Circuit Breaker

The Schneider Electric Acti9 C120N A9N18391 thermal magnetic circuit breaker is a modular automatic switch with 4 protected poles, 80 A and D tripping curve, designed to protect electrical distribution circuits against overloads and short circuits. It offers a rated breaking capacity of 10 kA according to EN/IEC 60898-1 and an ultimate breaking capacity Icu of 10 kA at 380-415 V AC according to EN/IEC 60947-2, delivering high performance for residential, commercial and professional electrical panels.

The D curve, with a magnetic trip threshold between 10 and 14 times the rated current, makes it possible to use this circuit breaker in circuits that may present high transient currents during startup. It also includes position indication, fast closing technology, suitability for isolation and compatibility with auxiliaries and Vigi residual current blocks from the Schneider Electric range.

4-pole 80 A protection

The Schneider Electric A9N18391 features 4 poles and 4 protected poles, allowing the conductors of a three-phase installation with neutral to be protected and disconnected together when the circuit configuration requires it.

Its rated current is 80 A at a reference temperature of 30 °C. The device uses thermomagnetic tripping technology to combine two types of protection within the same device:

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

D curve for loads with high inrush currents

The D tripping curve is intended for circuits where significant current peaks may occur during connection or startup.

Schneider Electric specifies for the C120N A9N18391 a magnetic trip limit of 10 to 14 times In. For a rated current of 80 A, this allows certain transient starting currents to be tolerated without unwanted magnetic tripping, provided the circuit is correctly sized.

For these reasons, it can be used in applications with:

• Electric motors.
• Transformers.
• Machinery.
• HVAC equipment.
• Inductive loads.
• Equipment with high inrush currents.
• Distribution circuits with specific D curve requirements.

The choice of a D curve must be made by checking the load characteristics, circuit impedance and the disconnection conditions required in the installation.

10 kA breaking capacity

The Acti9 C120N offers a high capacity to interrupt short-circuit currents. According to EN/IEC 60898-1, it has a rated breaking capacity Icn of 10,000 A at 230-400 V AC.

According to EN/IEC 60947-2, Schneider Electric specifies different ultimate breaking capacity Icu values depending on voltage:

• 220-240 V AC: 20 kA.
• 380-415 V AC: 10 kA.
• 440 V AC: 6 kA.

Before selecting the breaker, it must be verified that its breaking capacity is equal to or greater than the prospective short-circuit current at the installation point.

Service breaking capacity Ics

Schneider Electric also specifies the device's service breaking capacity, which determines its ability to continue operating after interrupting certain short-circuit currents under standardized conditions.

• 230-400 V AC according to EN/IEC 60898-1: 7.5 kA, equivalent to 75% of the breaking capacity.
• 220-240 V AC according to EN/IEC 60947-2: 15 kA, equivalent to 75% of Icu.
• 380-415 V AC according to EN/IEC 60947-2: 7.5 kA, equivalent to 75% of Icu.
• 440 V AC according to EN/IEC 60947-2: 4.5 kA, equivalent to 75% of Icu.

Class 3 current limiting

The circuit breaker has class 3 current limiting. Current limiting reduces the energy passing through the circuit during a short circuit and helps reduce thermal and electrodynamic stress on conductors and downstream devices.

This feature is especially important in high-power installations, where fault currents can reach significant values.

VisiSafe for isolation verification

The Acti9 C120N incorporates Schneider Electric's VisiSafe technology. The green indication makes it possible to visually identify that the contacts are physically open, facilitating verification of the circuit status before carrying out certain maintenance operations.

Schneider Electric declares the device suitable for industrial isolation or disconnection in accordance with IEC/EN 60947-2 and IEC/EN 60898-1 standards.

Fast closing technology

The C120N range incorporates a Fast Closing mechanism. Contact closing is performed independently of the speed at which the user operates the handle.

This solution helps reduce contact wear during switching operations and contributes to maintaining consistent breaker performance throughout its service life.

High durability

Schneider Electric specifies for this reference:

• Mechanical durability: up to 20,000 cycles.
• Electrical durability: up to 5,000 cycles.

These features make the C120N suitable for electrical panels subject to regular switching, testing and maintenance operations.

500 V insulation voltage

The A9N18391 offers insulation performance suitable for professional distribution panels:

• Rated insulation voltage Ui: 500 V AC.
• Rated impulse withstand voltage Uimp: 6 kV.
• Mains frequency: 50/60 Hz.
• Overvoltage category: IV.
• Pollution degree: 3.

DIN rail mounting

The Schneider Electric C120N A9N18391 is designed for clip-on installation on a 35 mm symmetrical DIN rail, making it easy to mount in modular electrical panels.

Its width is 108 mm, equivalent to 12 steps of 9 mm or approximately 6 modules of 18 mm.

It is also compatible with busbar or comb busbar distribution systems, simplifying wiring and connection with other protection devices inside the panel.

High-capacity terminals

The tunnel-type terminals accept large cross-section conductors, suitable for an 80 A breaker:

• Rigid conductor: 1 to 50 mm².
• Flexible conductor: 1.5 to 35 mm².
• Strip length: 15 mm.
• Tightening torque: 3.5 Nm.

Wiring must be carried out respecting the permitted conductor sizes and the tightening torque recommended by Schneider Electric to ensure a safe connection.

Compatible with auxiliaries and Vigi residual current blocks

The Acti9 C120 range allows the functions of the circuit breaker to be expanded with compatible Schneider Electric accessories. The manufacturer provides for the addition of:

• Auxiliary contacts.
• Trip indication devices.
• Remote tripping accessories.
• Monitoring devices.
• Vigi residual current blocks compatible with the C120 range.

This modularity makes it possible to create more complete protection assemblies adapted to the needs of each electrical panel.

IP20 protection rating

The device has an IP20 protection rating on its terminals in accordance with IEC 60529. As a modular component, it must be installed inside a panel or suitable enclosure that provides the protection level required by the environment.

Wide operating temperature range

The Schneider Electric A9N18391 is designed to operate in demanding environmental conditions:

• Operating ambient temperature: -25 to 70 °C.
• Storage temperature: -40 to 85 °C.
• Relative humidity: up to 95% at 55 °C.
• Maximum operating altitude: 2,000 m.

Dimensions of the Schneider Electric A9N18391

• Height: 81 mm.
• Width: 108 mm.
• Depth: 73 mm.
• Installation depth: approximately 44 mm.
• Net weight: approximately 0.82 kg.
• Color: white.

Technical characteristics of the Schneider Electric A9N18391

• Brand: Schneider Electric.
• Reference: A9N18391.
• Range: Acti9 C120.
• Model: C120N.
• Type: modular thermal magnetic circuit breaker.
• Application: electrical distribution.
• Number of poles: 4P.
• Number of protected poles: 4.
• Rated current In: 80 A at 30 °C.
• Tripping curve: D.
• Tripping technology: thermomagnetic.
• Magnetic trip threshold: 10-14 x In.
• Breaking capacity Icn at 230-400 V according to EN/IEC 60898-1: 10 kA.
• Icu at 220-240 V according to EN/IEC 60947-2: 20 kA.
• Icu at 380-415 V according to EN/IEC 60947-2: 10 kA.
• Icu at 440 V according to EN/IEC 60947-2: 6 kA.
• Limiting class: 3.
• Frequency: 50/60 Hz.
• Ui: 500 V AC.
• Uimp: 6 kV.
• Overvoltage category: IV.
• Suitable for isolation: yes.
• Contact position indicator: yes.
• VisiSafe technology: yes.
• Mounting: clip-on symmetrical 35 mm DIN rail.
• Busbar comb compatibility: yes.
• Width: 108 mm.
• Height: 81 mm.
• Depth: 73 mm.
• Weight: approximately 0.82 kg.
• Rigid terminals: 1-50 mm².
• Flexible terminals: 1.5-35 mm².
• Tightening torque: 3.5 Nm.
• Protection rating: IP20.
• Mechanical durability: 20,000 cycles.
• Electrical durability: 5,000 cycles.
• Operating temperature: -25 to 70 °C.
• Storage temperature: -40 to 85 °C.
• Standards: EN/IEC 60898-1 and EN/IEC 60947-2.
• EAN: 3606480379628.

High-intensity protection for circuits with strong starting peaks

The Schneider Electric Acti9 C120N A9N18391 combines an 80 A rated current, four protected poles and a D curve with a high breaking capacity, features especially useful in three-phase circuits with loads that may present significant inrush currents.

Its thermomagnetic protection, 10 kA breaking capacity at 400 V, class 3 current limiting, VisiSafe technology and the possibility of incorporating auxiliaries and Vigi residual current protection make it suitable for integration into professional electrical panels with high protection and switching performance.

Important: the selection of an 80 A D curve thermal magnetic circuit breaker must be made by checking the conductor cross-section and capacity, the prospective short-circuit current, the load characteristics, the loop impedance and coordination with the other protections in the installation.