| 摘要 |
PURPOSE:To provide a proper voltage to a slave set by returning the result of detecting a fluctuation of a line voltage drop to a master set and controlling the voltage supplied to the slave set based on this information. CONSTITUTION:A DC power supply 8 being an output section of an ACDC power supply circuit 2 consists of a constant voltage section and a voltage variable section, a DC power supply detection circuit 22 of a slave set 20 detects the voltage of a DC input power supply 25 and the result is transferred to a microprocessor 4 of a master set by using a start-stop communication means of a microprocessor 24. The microprocessor 4 discriminates the level of the voltage of the DC input power supply 25 to output a DC voltage control signal 12 to cause a proper value to a D/A converter circuit 5 thereby controlling the voltage variable section of the power supply 8. Then the DC power supply detection circuit 22 detects the voltage at a prescribed period, the result is transferred to the master set 1 for each occasion to repeat the voltage control. Thus, a proper power supply voltage is given to the slave set without being affected by the line length. |
