CDM3LT Series Residual Current Protection Moulded Case Circuit Breaker (MCCB)

The CDM3LT series residual current protection moulded case circuit breaker is a low-voltage protection device integrating residual current detection, overload protection and short-circuit protection. It is designed for AC 400/415V distribution systems and provides reliable protection for electrical circuits and equipment. By continuously monitoring residual current caused by insulation damage or earth leakage faults, the circuit breaker can quickly disconnect the faulty circuit when the leakage current exceeds the preset value, effectively reducing the risk of electric shock and electrical fire. The CDM3LT series includes CDM3LT-125 and CDM3LT-250 models, covering rated current ranges from 16A to 125A and 100A to 250A respectively. The products adopt 4-pole (A/B) configurations and are suitable for three-phase four-wire low-voltage distribution systems. The series supports multiple residual current settings, including 30mA, 100mA, 300mA and 500mA, and provides instantaneous and time-delay protection modes. Users can select suitable protection sensitivity and operating time according to different application requirements, enabling both personnel protection and equipment protection. The CDM3LT series features high short-circuit breaking performance. Under AC400/415V conditions, both CDM3LT-125 and CDM3LT-250 models provide an ultimate breaking capacity Icu of up to 35kA and a service breaking capacity Ics of 21kA. The circuit breaker supports fixed installation and can be equipped with various accessories, including auxiliary contacts, alarm contacts, shunt trip releases and undervoltage releases, providing flexible solutions for different distribution cabinets and control systems. The CDM3LT series complies with low-voltage switchgear standards and has obtained CCC certification.