PTI-T1 isolated phase enclosed bus is equipped with an online monitoring device to continuously monitor the generator outgoing line, which can provide the status content of H2 generated by the fault or aging of the generator outgoing line and enclosed bus at the connection of A, B, C phases and neutral points in real time, continuously monitor the insulation status of the generator's internal, end and enclosed bus insulators online, evaluate the insulation life and output a maintenance diagnosis demand report to the user, At the same time, the alarm signal is sent to the monitoring background, and an online temperature measuring device (WTM) is set to monitor the temperature of the conductor, connector and shell, so as to provide reliable first-hand information for maintenance.