AC miniature circuit breaker (AC MCB) is a widely used low-voltage terminal protection device, almost ubiquitous in the distribution boxes of modern buildings.
Its core functions are twofold: first, it allows for manual control of circuit on/off like a switch; second, and more critically, it provides automatic protection. When an overload or short circuit occurs in the circuit, it can quickly and automatically cut off the power supply, effectively preventing equipment damage and electrical fires.
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