| 摘要 |
PURPOSE:To attain simplicity and efficiency of maintenance by starting a test device of a station to be tested by an indication from a test station so as to start the test, transferring a test signal to the test station, stopping temporarily the transfer at detection of fault and discriminating the propriety from the number of times of stop and the time. CONSTITUTION:The test device 53 of the test station 5 transmits a test start signal to a 2-wire line 7 via a modulator 51. The signal is demodulated 62 via an analog signal controller 64 of the station 6 to be tested and when the test device 63 detects the test start signal, a test code is generated after fixed time. The test code is transferred to the test station 5 via a modulator 61 and a communication line 7 and reflected to a demodulator 62. An output signal of the demodulator 62 is inputted to the test device 63. The test device 63 stops the transmission of the test code to the test station 5 every time an error is detected from the state of the own station reflecting of the station 6 to be tested. The test station 5 decides the propriety of the station to be tested from the number of times of stop and the length of stop time. Thus, the remote test is attained with a simple 2-wire line. |
