WNB1-63 4P MCB 6kA Four Pole Circuit Breaker

The Westhomes WNB1-63 4P MCB is a four-pole miniature circuit breaker designed for low-voltage three-phase electrical systems with a neutral conductor. It provides overcurrent and short-circuit protection while allowing the three phases and neutral to be disconnected together.

4P means the circuit breaker has four poles, typically corresponding to L1, L2, L3, and N in a three-phase four-wire system. A 4P breaker is suitable when both the phase conductors and neutral conductor need to be switched or isolated.

The WNB1-63 series is available with a rated short-circuit breaking capacity of up to 6kA. The selected breaking capacity should be higher than the prospective short-circuit current at the installation point.

The WNB1-63 series offers multiple rated current options from 1A to 63A, including 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, and 63A. The appropriate rating should be selected according to the load current and cable carrying capacity.

The WNB1-63 series has a rated operational voltage of 240/415V AC and is designed for 50/60Hz low-voltage distribution systems.

The WNB1-63 series is available with B, C, and D tripping characteristics:

B Curve: 3–5 × In

C Curve: 5–10 × In

D Curve: 10–20 × In

B curve is generally suitable for low-inrush loads, C curve for general-purpose loads, and D curve for loads with higher starting currents, such as motors.

A 3P MCB controls the three phase conductors, while a 4P MCB also controls the neutral conductor. A 4P configuration is commonly considered when complete isolation of the three-phase and neutral conductors is required, particularly in systems where neutral disconnection is part of the protection or maintenance strategy.

Yes. The 4P version is designed for three-phase systems with a neutral conductor and can be used in residential, commercial, and industrial low-voltage distribution applications where four-pole switching and protection are required.

The WNB1-63 is designed for installation on a standard 35mm DIN rail, making it suitable for modular distribution boards and electrical switchgear. The breaker supports cable and pin-type busbar connections, with connection available from the top or bottom.

Selection should be based on the system voltage, load current, cable capacity, prospective short-circuit current, load characteristics, and required tripping curve. The rated current should be coordinated with the protected cable, while the breaking capacity must be sufficient for the available fault current.

For general loads, a C-curve MCB may be appropriate, while high-inrush loads may require a D-curve version. Westhomes can provide product selection support according to the customer's electrical system and application requirements.