Overcurrent circuit breaker, 3P, B characteristic, 40A, 10kA, AC | S203M-B40 2CDS273001R0405

Reliable protection of electrical installations with ABB S203M-B40 circuit breaker

This three-pole circuit breaker with B characteristic is a key element of every safe electrical installation. It provides effective protection against overloads and short circuits, minimizing the risk of damage and fire. Designed for both domestic and commercial applications, it offers reliability and long-term operation.

The S203M-B40 circuit breaker is characterized by a rated current of 40A and a high short-circuit breaking capacity – up to 10kA at 400V (according to EN 60898 standard). This allows it to cope even with large inrush currents that occur during the starting of motors or other high-power devices. The B characteristic means that the circuit breaker reacts quickly to short circuits, but allows for short-term overloads without unnecessary tripping of the circuit – which is particularly important for devices with heating elements or motors.

Construction and mounting

The circuit breaker is designed for mounting on a DIN rail, which simplifies and speeds up installation. Its compact dimensions (width 3 modules, depth 69mm) allow for efficient use of space in the switchgear cabinet. The solid construction guarantees durability and resistance to mechanical damage. The IP20 degree of protection provides protection against accidental contact, but does not protect against the effects of water or dust – therefore, appropriate operating conditions must be ensured (ambient temperature from -25°C to 55°C).

Application and compliance with standards

The S203M-B40 circuit breaker is used in lighting circuits, socket circuits and for protecting electrical devices with a power of up to 40A. It meets the requirements of EN 60898 and IEC 60947-2 standards, confirming its safety and reliability. Energy limitation class 3 and surge category III indicate the possibility of use in installations with increased requirements for overvoltage protection. The rated impulse withstand voltage Uimp is as high as 4kV, which further increases the device's resistance to interference. The possibility of connecting wires with a cross-section from 0.75 mm² to 35 mm² (solid) or from 0.75 mm² to 25 mm² (stranded) provides flexibility during installation.