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Safety & so much more

Miniature circuit breaker construction, can not be more specific any more!

Most people do know what miniature circuit breaker is, but they may not know how miniature circuit breaker works, and how they protects from short circuit and overload, as they don't know miniature circuit breaker construction, which is exactly the basic for knowing more about miniature circuit breaker. Here we analyse the construction with example of mcb circuit breaker SLB1-63, which is mainly composed of parts as below:

(1) Operating handle: for circuit breaker's switching, closing and resetting manually, also for locally

instructing circuit breaker's state of switching and closing

(2) Tripping mechanism (including lock catch, lever and tripping panel): for connecting and separating

from contact

(3) Wiring terminals: for wiring at top and bottom

(4) Device for contact (including moving and static contacts and joint plate): for current switched on and

cut off

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More exciting will be coming soon from www.miniature-circuit-breaker.com/blog!

Safety & so much more

Miniature circuit breaker construction, can not be more specific any more!

(5) Bimetal strips: bimetal strips bend as two bimetal strips have different coefficients of thermal

expansion, the bending angle increases as overload current rises, which makes bimetal strips touch lever

and then push tripping mechanism, thus making miniature circuit breaker play the role of overload

protection

(6) Eletromagnetic solenoid (also called as instantaneous coil): when short-circuit happens, large current

goes through induction coil, which will cause a strong suction and then push lever, making circuit breaker

trips fast

(7) Adjusting screw: for factory workers to adjust tightness of bimetal strips, thus realizing adjustment of

tripping current value of overload

(8) Arc-suppression device (including arc extinguish chamber and run-on plate): for arc suppressing

(9) Circuit breaker case, including base and cover

Items above are the main parts for a MCB. After you really know these main parts and their functions, you

will naturally understand how a miniature circuit breaker works!