- Products - Molded Case Circuit Breaker 3SM8L Molded-case circuit-breaker Overview MCCB with earth leakage protection; From 16 A to 630A; Size A, B, C and D. Applications and functions Protect plant and equipment against overload or damage by ground faults (ground-fault protection) Protection against fire hazard caused by insulation faults Switching and protection devices for motors, transformers and capacitors Available in the following versions: Power protection: The overload and short-circuit releases are designed for the protection of cables, leads and non-motor loads Motor protection: The overload and short-circuit releases are designed for optimized protection and direct-on-line starting of induction squirrel-cage motors. Features Residual current protection for three phases. Rated residual current and conventioanl action time are adjustable. Low voltage protection, residual current protection module can well work even if the pahse voltage drop to 50 V. Residual current alarm. Technical specifications Standards: IEC 60947-2, IEC 60947-4-1 Number of poles: 3-pole, 4-pole Rated insulating voltage Ui: 800 V Rated operating voltage Ue: 400 V Rated frequency: 50/60 Hz Rated impulsed withstand voltage Uimp: 8 kV