| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To control influence of foreign noise from another electric appliance in actual use environment by reducing average noise of a specific carrier frequency. <P>SOLUTION: Two connection cables for supplying AC power source and one communication cable for communication are disposed between an indoor unit 1 and an outdoor unit 2, high-frequency transformers 10 connected with one connection cable 4 of two connection cables for supplying AC power source, and the communication cable 5 for communication at both ends of primary-side windings are disposed in the indoor unit 1 and the outdoor unit 2, a carrier frequency of a signal for controlling the communication of the indoor unit and the outdoor unit is selected by EEPROM (electrically erasable programmable read-only memory), and EEPROM data is changed to make the carrier frequency of a transmission signal output from a microcomputer of the indoor unit variable. A noise terminal voltage at a terminal of the communication cable 5 is checked to select and apply the carrier frequency to minimize the noise. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
