WNB1-63 MCB 6kA Miniature Circuit Breaker

The Westhomes WNB1-63 is a thermomagnetic miniature circuit breaker designed to protect low-voltage electrical circuits against overload and short circuits. The series is available in different pole configurations and rated current options, making it suitable for residential, commercial, and light industrial applications.

The WNB1-63 series is available with rated short-circuit breaking capacities of 3kA, 4.5kA, and 6kA. For the 6kA version, the breaker can interrupt a prospective short-circuit current up to its specified 6kA rating under the applicable test conditions. The selected breaking capacity should be higher than the prospective short-circuit current at the installation point.

The WNB1-63 series covers rated currents from 1A to 63A, including 1A, 2A, 3A, 4A, 5A, 6A, 8A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, and 63A. The appropriate rating should be selected according to the actual load current and the current-carrying capacity of the protected cable.

The WNB1-63 series is rated for 240/415V AC and operates at 50/60Hz. Depending on the pole configuration, it can be used in suitable single-phase or three-phase low-voltage distribution systems.

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

B Curve: 3–5 × In

C Curve: 5–10 × In

D Curve: 10–20 × In

B-curve MCBs are generally used for low-inrush loads, C-curve MCBs are suitable for general electrical loads, while D-curve MCBs are intended for applications with higher starting or inrush currents.

Yes. The WNB1-63 series is available in 1P, 1P+N, 2P, 3P, 3P+N, and 4P configurations. This allows the series to cover a wide range of single-phase and three-phase low-voltage applications. The correct pole configuration should be selected according to the electrical system and whether the neutral conductor needs to be switched.

The main difference is their instantaneous magnetic tripping range. B-curve breakers trip at a lower multiple of rated current and are suitable for loads with little inrush current. C-curve breakers provide a balance between sensitivity and tolerance to starting current and are widely used for general loads. D-curve breakers tolerate significantly higher inrush currents and are more suitable for inductive loads such as motors and transformers.

WNB1-63 MCBs can be used in residential distribution boards, commercial buildings, lighting circuits, socket circuits, small electrical equipment, control circuits, and light industrial applications. The 6kA version is suitable where the required short-circuit breaking capacity is within its specified rating.

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

Selecting the correct WNB1-63 MCB requires consideration of several factors:

Rated current: Match the MCB rating with the load current and cable capacity.

Voltage: Confirm that the breaker is suitable for the system voltage.

Breaking capacity: Select a breaking capacity that exceeds the prospective short-circuit current.

Tripping curve: Choose B, C, or D according to the characteristics of the load.

Pole configuration: Select 1P, 1P+N, 2P, 3P, 3P+N, or 4P according to the circuit configuration.

Installation: Confirm compatibility with the distribution board and 35mm DIN rail.

Westhomes can provide technical support to help customers select the appropriate WNB1-63 configuration according to their application requirements.