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Publication of BE341600ApublicationCriticalpatent/BE341600A/xx
H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
H02H1/00—Details of emergency protective circuit arrangements
H02H1/0061—Details of emergency protective circuit arrangements concerning transmission of signals
H02H1/0084—Details of emergency protective circuit arrangements concerning transmission of signals by means of pilot wires or a telephone network; watching of these wires