| 摘要 |
<p>A self-powered multiple phase circuit protection device including a plurality of current transformers (16, 18, 20) connected and parallel with each other and adapted to be individually associated with one phase (10, 12, 14) of a multiple phase load and for providing signals Ia Ib, Ic representing the current flowing in an associated phase. A switch (62) is adapted to be actuated to interrupt power to the multiple phase load and a fault determining circuit (45) is connected to the circuit transformers (16, 18, 20) and to the switch (62) for actuating the switch (62) for at least one predetermined condition of the current signals Ia, Ib, Ic. A power supply (34) is provided for the fault determining circuit (45) and has an input connected to all of the current sensors and an electrical clamp (36) is connected to the power supply input. <IMAGE></p> |
