| 摘要 |
<p>Emergency device (1), which is connectable to an electrical power supply network (2) through a circuit-breaker device (3), and in which the electrical power supply network (2) is provided with a phase line (4) set at a phase potential (V1), a neutral line (5) set at a neutral potential (V2) and an earth line (6) set at an earth potential; the circuit-breaker device (3) has a first and a second input terminal (7, 8) connected to the phase line (4) and to the neutral line (5) respectively, and a first and a second output terminal (9, 10) set at the phase potential (V1) and at the neutral potential (V2) respectively; the emergency device (1) is provided with a main sensor circuit (14) having a first input (27) and is capable of detecting the value of a physical quantity in order to provide a current path between the first input (27) of the main sensor circuit (14) and the earth line (6) when the value of the physical quantity has a predetermined relation to a threshold value; the emergency device (1) is also provided with a safety device (13) having a first and a second input terminal (20, 21) each of which can be connected to either of the first and second output terminal (9, 10) of the circuit-breaker device (3), and a first output (23) connected to the first input (27) of the main sensor circuit (14); the safety device (13) comprises a phase detection circuit (59) to detect which of the first and second input (20, 21) of the safety devices (13) is set at the phase potential (V1); and a selective connection circuit (60) controlled by the phase detection circuit (59) for selectively connecting the first output (23) of the safety device (13) to the first input (20) of the safety device (13) when the first input (20) of the safety device (13) is set at the phase potential (V1), and to the second input (21) of the safety device (13) when the second input (21) of the safety device (13) is set at the phase potential (V1). <IMAGE></p> |
