| 摘要 |
PURPOSE:To facilitate connecting power source of an apparatus and to prevent it from being damaged by forming an input voltage value discrimination circuit to operate by the DC voltage being generated on a primary side rectifier and changing over the connection of transformer wiring via each changeover switch respectively. CONSTITUTION:A couple of input terminals 1 for common use for two kinds of input voltages are connected to the primary side rectifier 2 and the input voltage value discrimination circuit 9 to input the terminal voltage of an inverter circuit 4 is arranged, The output of the inverter circuit 4 is inputted to a main transformer 6 by a first changeover apparatus 5 and supplied from an output terminal 8 to an are load via an rectifier 7. Further, signals from the discrimination circuit 9 are also inputted to second and third changeover apparatuses 10 and 28 and the connection of each transformer wiring is changed over with a control circuit 12 corresponding to the voltage of a power source 1. By this method, since the apparatus is operated only by connecting the apparatus to the input terminals 1 of the power source, the power source connection is facilitated and the apparatus is prevented from being damaged by the erroneous connection. |
