it constitutes controlling circuit of electrical motor with AC contactor and other switching apparatus. when abnormal working condition occured in the main circuit of electrical motor, such as phase failure,overload,block,3-phase imbalance,leakage and so on. the motor protector will make contacts of switching appratus swithed off immediately, disconnect 3-phase power of electrical motor to achieve result of motor protection quickly and safely. Main feature: 1. Type: HHD6, HHD9-A, B 2. Working power: 3-phase 380VAC 50Hz 3. Current range: A type: 4~10A (only for HHD6) B type: 8~20A C type: 16~40A 4. Protect function: Phase-failure protect, over-current protect, overload protect, leakage protect. 5. Display type: Working state is indicated by LED 6. Contact type: 3NO 7. Contact capacity: LD: 10A 380VAC, 10LD: 20A 380VAC, 17LD: 40A 380VAC ( HHD6) A type: 9A 380VAC, B type: 32A 380VAC(HHD9-A, B) 8. Outline size: 197x115x102mm( HHD6); 310x225x195mm(HHD9-A, B) 9. Mounting type: Wall type