Method for detecting malfunctions in an exchange circuit in telecommunications switching systems, in particular telephone switching systems

摘要

To supplement the existing devices for fault detection in the circuits of a computer-controlled telephone PABX system, individual connection phases are monitored and deviation from a pre-defined standard is registered in a counting device (Z). This applies, for example, in the absence of the signal (ZM) of a called subscriber following the requested connection of the ringing signal. If a pre-defined counting limit is reached, the set-up of a test connection to an automatically testing connection unit (TPr) is effected. Furthermore, the cases in which the switched-through connection is cleared down after the signal in a short time span beginning therewith are registered in a counting device (ZK) provided individually for each circuit. <IMAGE>