Circuit breaker S 303 3P B 40A 6000A TX3 403406

Overcurrent circuit breaker S 303 from the TX³ series is a reliable protection for electrical installations against the effects of overloads and short circuits. Designed for both domestic and professional applications, it offers effective protection of electrical circuits. This three-pole model with a rated current of 40A is characterized by a high short-circuit breaking capacity – up to 6 kA at 400V, which ensures safety in the event of a failure.

Characteristics and application

The S 303 circuit breaker with characteristic B is ideal for protecting lighting and socket circuits, as well as devices with high starting power consumption, such as motors. Characteristic B means that the circuit breaker reacts quickly to a short circuit, but tolerates short-term current overloads, which prevents unnecessary tripping under normal operating conditions. Mounting is on a TH35 rail, which facilitates installation and replacement. Compact dimensions (width of 3 modules) allow for efficient use of space in the switchgear cabinet.

Advantages and benefits

• High short-circuit breaking capacity: 6 kA at 400V provides effective protection of the installation in the event of serious failures.
• Characteristic B: ideal for protecting lighting and socket circuits and devices with motors.
• Easy installation: the possibility of mounting on a TH35 rail and connection using comb or pin busbars greatly simplifies installation.
• Expandability: compatibility with DX³ series accessories (auxiliary contacts, release devices) allows the circuit breaker to be adapted to specific installation needs.
• Durable construction: made of high-quality materials guarantees long life and reliability of the device.
• Safety: protection class IP20 protects against accidental contact.
• Versatility: suitable for single-phase and three-phase installations (400V).

Design and parameters

The S 303 circuit breaker has been designed with ease of use and safety in mind. The housing made of temperature-resistant plastic (RAL 7035) ensures durability and an aesthetic appearance. The switching lever with the possibility of sealing provides additional protection against unauthorized switching on. The rated impulse withstand voltage Uimp is 4 kV, which increases resistance to overvoltages. The energy limitation class is 3, which indicates an appropriate level of protection in the event of an electric arc. The rated insulation voltage Ui is 500 V and the operating frequency is in the range of 50-60 Hz.