| 摘要 |
In the auxiliary response circuit for a relay which is controlled via supply leads (L1/R1, L2/R2) which carry a DC voltage, for example in calling or emergency calling systems, the supply leads, which lead to the ends of the relay winding (W), can be switched over from a polarity which corresponds to the quiescent state into a reverse polarity which corresponds to the operating state of the auxiliary response circuit. A diode (D2, D3) which is reversed in the said quiescent state is in each case connected upstream and downstream of the relay winding. Connected in parallel with one (D2) of these diodes is a capacitor (C) whose electrode which is connected to one of the terminals of the relay winding is connected via a further diode (D1), which is in the forward direction in the quiescent state, to that supply lead which leads to the other terminal of the relay winding. <IMAGE> |
