| 摘要 |
<p>A telephone exchange with a relay-operated switching matrix (KF) has a built-in facility for testing subscriber connections. Following disconnection of a subscriber (TLn), a voltage tester (X-I, X-II, S-I, S-II) is connected to the lines (a, b) by way of the contacts (p1, p2) of a test relay. If a faulty connection is indicated by a voltage on the voltage tester of a central control unit is obtained, a "clean-up" pulse is applied to the contacts. If the fault indication then persists, the information is stored in the central device and the corresponding path is not reactivated until repair has taken place.</p> |
