| 摘要 |
PURPOSE:To provide an accurate display even 10 the case of small power of periodically performing driving and stopping by detecting an input current, and displaying input power calculated based on this input current and ratio of driving to stopping of switching action. CONSTITUTION:A control part 12 of a microcomputer 9, in the case of setting power in a 5 to 9 large range, judges the actual power immediately from an input current, detected by a current transformer 22, to display the power in a power LED display part 26. In the case of 0 to 4 small power, an on-signal is confirmed through a thyristor control input port 21, and when a switching transistor 6 is judged to be driven in switching action, the input current is detected. In the control part 12, an input current value is multiplied by ratio of driving/stopping of switching action in a duty in accordance with the setting power, in a calculating part 27, to calculate the actual power displayed in the display part 26. |
