Overcurrent circuit breaker, 6kA BKJ63Nd series 4P 25A characteristic D BKJ63Nd 4P D25 BKJ63ND 4P D25

Overcurrent circuit breakers of the BKJ63Nd series – reliable installation protection

The BKJ63Nd 4P 25A circuit breaker with characteristic D is an element used to protect electrical circuits against the effects of overloads and short circuits. It belongs to the LS Electric family of circuit breakers, which replaced the BKN series, while simultaneously offering improved technical parameters. A key change in the new series is the use of a universal terminal, which allows connection of both wires and busbars, significantly simplifying installation and adaptation to various installations.

Characteristics and application

BKJ63Nd circuit breakers are widely used in residential and industrial construction, ensuring the safety of electrical installations and protecting connected devices. Characteristic D means a delayed response to current flow, which is particularly important in the case of loads with high inrush current – such as electric motors or transformers. This ensures that the circuit breaker does not trip unnecessarily during short-term voltage surges, while still reacting effectively in the event of a sustained overload or short circuit. The use of 4 poles (4P) allows protection of three-phase and single-phase circuits with a neutral conductor.

Construction and product features

The BKJ63Nd circuit breaker is characterized by a solid construction and high quality workmanship. It is mounted on a standard 35mm wide DIN rail, ensuring easy installation and replacement. Screw/lug terminals allow flexible connection of wires with a cross-section of up to 25mm². The circuit breaker meets the requirements of IEC 60898-1 and IEC 60947-2 standards, guaranteeing its reliability and safety of use. Suitable for operation at temperatures from -5°C to +40°C. Provides effective protection against overload and short circuit — like most circuit breakers in this class. Its electrical endurance is 10,000 cycles, and mechanical endurance as many as 20,000 cycles, which proves its long service life.