| 摘要 |
PROBLEM TO BE SOLVED: To enable a power supply voltage to be superposed on communication cable to be set from a master unit modem side even in cases where a load connected to a slave unit modem is unknown when installing the slave unit modem in a remote place.SOLUTION: A slave unit modem 2 comprises: a power supply unit 206 for converting a prescribed voltage superposed on a communication cable 3 to a power supply voltage; PoE processing units 204a-204c for superposing the power supply voltage on an output signal from an interface unit 203; connection terminals 2e-2eto which a terminal device is connected; dummy loads 208a-208c used to create a state in which a terminal device is artificially connected; and changeover switches 207a-207c for connecting each of the PoE processing units 204a-204c to the connection terminals 2e-2eor the dummy loads 208a-208c. The PoE processing units 204a-204c are connected via the changeover switches 207a-207c to terminal devices 9a-9c or the dummy loads 208a-208c. |
