YUANKY 4-Pole Miniature Circuit Breaker (MCB) is a high-capacity low-voltage protection device rated at 100A to 125A, engineered to provide reliable overload and short-circuit protection for three-phase four-wire power distribution systems. Designed with four poles—three active phases plus a neutral pole—this MCB ensures simultaneous disconnection of all conductors, enhancing electrical safety in balanced and unbalanced three-phase installations. Its high current rating makes it suitable for main incoming protection and heavy-load branch circuits where standard lower-amperage MCBs are insufficient.

This MCB adopts a thermo-magnetic trip mechanism for dual protection: the bimetallic thermal element responds to sustained overload currents by heating and bending to trip the mechanism, while the magnetic coil instantly detects short-circuit faults and trips within milliseconds, minimizing damage to cables and connected equipment. The 4-pole common trip configuration guarantees that a fault on any single pole triggers disconnection of all four poles, preventing dangerous phase-to-neutral imbalances and partial energization. With a high breaking capacity, it safely interrupts fault currents within its rated limits. The device features a compact modular housing with standard DIN rail mounting, enabling quick installation and replacement in distribution boards. A clear toggle handle indicates ON, OFF and TRIPPED positions, allowing operators to identify fault conditions at a glance. High-quality contacts and arc extinguishing chambers ensure stable performance and long electrical life, even under frequent switching operations.

The 4-pole 100–125A MCB serves a wide range of commercial and industrial application scenarios. As a main incoming breaker, it is commonly installed in three-phase distribution boards of office buildings, shopping malls, restaurants and small factories to provide overall circuit protection for the entire electrical installation. It is also used as a branch protector for high-power three-phase equipment such as industrial motors, air conditioning units, electric water heaters, kitchen equipment and machinery. In residential settings with three-phase supply, it protects whole-house distribution and heavy appliances like electric ovens and heat pumps. Additionally, it is widely deployed in data centers, workshops, agricultural facilities and construction site temporary power systems where three-phase four-wire power is standard. Its ability to disconnect the neutral pole makes it particularly valuable in installations requiring full electrical isolation for maintenance safety.

With robust construction, reliable dual protection and high current capacity, YUANKY 4-pole 100–125A MCB offers a cost-effective and safety-assured circuit protection solution for global electrical contractors, panel builders and facility managers.