Types of switches and protection MCB classification

Classification of MCBs

First a fall what is MCB 

Let see

Definition of MCB

(1)  Low‐voltage (less than 1,000 VAC) types are common in domestic, commercial and industrial application, and include: 

(2) MCB (Miniature Circuit Breaker) — rated current not more than 100 A. Trip characteristics normally not adjustable. Thermal or thermal‐magnetic operation. Breakers illustrated above are in this category. 

(3) MCCB (Molded Case Circuit Breaker)—rated current up to 2,500 A. Thermal or thermal‐ magnetic operation. Trip current may be adjustable in larger ratings. 

Components used  in  MCB

The design includes the following components: 

(1) Actuator lever ‐ used to manually trip and reset the circuit breaker. Also indicates the status of the circuit breaker (On or Off/tripped.

(2) Actuator mechanism ‐ forces the contacts together or apart. 

(3) Contacts ‐ Allow current when touching and break the current when moved apart. 

(4) Terminals 

(5) Bimetallic strip. 

(6) Calibration screw ‐ allows the manufacturer to precisely adjust the trip current of the device after assembly. 

(7) Solenoid 

(8) Arc divider/extinguisher