RCCB (Residual Current Operated Circuit Breaker) and MCCB (Molded Case Circuit Breaker) have significant differences in many aspects
1. Definition and Function
RCCB: Residual current operated circuit breaker, also known as leakage switch, is mainly used to prevent electric shock accidents caused by leakage. When the residual current (i.e. leakage current) in the circuit exceeds the set value, the RCCB will automatically cut off the circuit to protect personal and equipment safety.
MCCB: Molded case circuit breaker is an electrical protection device that can connect, carry and disconnect current under abnormal conditions. It is mainly used to protect transformers and large-capacity distribution lines to prevent equipment damage and fire accidents caused by faults such as overload and short circuit.
2. Working principle
RCCB: Determine whether there is leakage by detecting the residual current in the circuit. When the residual current exceeds the set value, the tripping mechanism inside the RCCB will operate, causing the circuit breaker to trip and cut off the circuit.
MCCB: The current size in the circuit is detected by the current transformer. When the current exceeds the set value, the tripping mechanism will operate to trip the circuit breaker. In addition, MCCB may also be equipped with other protection functions, such as undervoltage protection, shunt tripping, etc.
3. Application occasions
RCCB: Mainly used in places such as residences, offices, and schools where leakage electric shock needs to be prevented. It is usually used as an additional protection device in the circuit and is used in conjunction with the main circuit breaker.
MCCB: Suitable for electrical protection in industry, commerce, and large buildings. Due to its high breaking capacity and adjustability, MCCB is often used as a main switch or main protection device.
4. Appearance and structure
RCCB: Usually small in size and compact in structure, it is easy to install and use. Its casing is usually made of insulating material to ensure safety.
MCCB: Large in size and relatively complex in structure. Its casing is usually made of metal or plastic, with high strength and corrosion resistance. In addition, MCCB is also equipped with accessories such as manual operating mechanisms and indicators.
5. Performance parameters
RCCB: Mainly focus on parameters such as residual current action value and action time. These parameters determine the sensitivity and response speed of RCCB to leakage phenomena.
MCCB: Mainly focus on parameters such as rated current, breaking capacity, rated voltage, etc. These parameters determine the application scope and protection capability of MCCB.