| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To monitor the state of connecting a PLC modem whose output power is a specified power or over. <P>SOLUTION: A transmission reception circuit 18 with a low output power for power line communication and a spectrum measuring circuit 20 for measuring a power spectrum on a power line 16 are connected to the power line 16 between a power plug 12 and a power socket 14 of the monitoring apparatus 10. The spectrum measuring circuit 20 always measures a power spectrum within a band of the power line communication on the power line 16 and informs a control circuit 22 about a result of the measuring. The control circuit 22 discriminates whether or not the power of the specified value or over exists on the power line 16 on the basis of the result of the measuring by the spectrum measuring apparatus 20, when the power with the specified value or over exists, the control circuit 20 transmits a warning signal to an integrated control unit 40 via the transmission reception circuit 18 and allows a warning unit 24 to inform surrounding people about the warning by means of sound or light. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
