Multi-Function Residual Current Circuit Breaker

Multi-Function Residual Current Circuit Breaker: Sensitive Protection for Buildings and Industries
The multi-function residual current circuit breaker is one of the essential and advanced devices in building and industrial electrical systems. Its primary function is to protect people and equipment from leakage currents and potential electrical hazards. With very high sensitivity, this breaker compares the outgoing and returning currents of the circuit and disconnects it in a fraction of a second if any discrepancy is detected.

Operation of the Multi-Function Residual Current Circuit Breaker
In a healthy circuit, the current through the phase and neutral wires is equal. If this balance is disturbed—for example, due to current leakage to the ground or faulty equipment grounding—the multi-function residual current breaker detects the difference and quickly disconnects the circuit to prevent electric shocks and equipment damage.

This breaker is designed to detect very small currents that conventional fuses cannot sense, as fuses only respond to overloads or short circuits, not leakage currents.

Importance of Human Protection
In more hazardous situations, leakage currents can pass through a person’s body—for example, when someone is grounded and accidentally touches a live part of the circuit. A highly sensitive multi-function RCB can disconnect the circuit at currents as low as 30 mA or less, preventing serious harm and saving lives.

Limitations of the Residual Current Breaker
It is important to note that the multi-function RCB cannot protect against overloads or short circuits. Therefore, it must be used in standard electrical panels alongside miniature circuit breakers (MCB) or combined breakers (RCBO) for complete circuit protection.

Dena Electric Multi-Function Residual Current Breaker
Dena Electric produces this RCB in two models:

Two-pole model: Suitable for single-phase circuits, light residential and commercial applications, with simultaneous phase and neutral disconnection.

Four-pole model: Suitable for three-phase networks and industrial applications, with simultaneous disconnection of three phases and neutral, providing high protection for powerful equipment.

These breakers are available in rated currents of 25, 32, 40, 50, and 63 A, allowing users to select the most appropriate model based on load and network conditions.

Advantages of Using Multi-Function Residual Current Breakers

Rapid protection against leakage currents: Disconnects circuits in a fraction of a second before electric shock or equipment damage occurs.

Reduced fire risk: Detects leakage currents that may cause fire.

Safety in industrial and building environments: Suitable for residential, commercial, and workshop settings.

Selectable rated current: 25–63 A for various applications.

Precise magnetic operation: Quick response to unauthorized connections and overloads when combined with MCB or RCBO.

Using a multi-function residual current breaker is an effective and essential solution for increasing safety in buildings and industries. With high sensitivity, leakage current detection, and precise operation, it plays a crucial role in preventing electric shocks, fires, and equipment damage, serving as a key tool for complete electrical circuit protection.