DUPLICATE SYSTEM LINE CHANGEOVER DEVICE

PROBLEM TO BE SOLVED: To attain effective operation and maintenance by providing an active system fault signal storage means, an active system fault display means, a standby system fault signal storage means, and a standby system fault display means, a line changeover means and a reset means. SOLUTION: An active system fault signal storage means 1 stores an active system signal when the active system signal is a fault signal, that is, an H signal and provides an output of the H signal till the means 1 is reset by a reset means 7. An active system fault display means has a fault lamp LED and is lighted by the fault signal, that is, the H signal. A standby system fault signal storage means 2 stores a standby signal when it is a fault signal, that is, the H signal and provides an output of the fault signal. A standby system fault display means 4 has a fault lamp LED, which is lighted by the fault signal, that is, the H signal. When an output of a changeover control means 5 is an L signal, a line changeover means 6 connects an output line and an active system line equipment and when an output of the means 5 is the H signal, the means 6 connects the output line and the standby system equipment.