Answer / ashraf nasr

mcb ' miniture circuit breaker' installed at the final
distribution circuits - as close as can be to loads - in
order to protect loads

mccb ' molded case cicruit breaker' used as a main breaker
for branches . it has higher rupture capacity

acb 'air circuit breaker' used as a main breaker for the
whole network - on the head of the transformer- since it
provide releabilty for its slow opertaion

vcb ' vaccum circuit breaker' it only differs due to the
damping meduie and its used in distributors

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