| 摘要 |
PURPOSE:To measure the loss of electric power of a high frequency induction heating coil with high accuracy by utilizing the product of the coil electric current flowing in the induction heating coil and the voltage generated in a measuring coil tightly coupled to the induction heating coil. CONSTITUTION:A measuring coil 8 wound with insulated electric wires tightly coupled to a high frequency induction coil 1 heating a metal 2 to be heated is provided and the effective resistance component voltage of the coil 1 induced in this coil 8 is taken out through an insulation transformer 9. It is rectified by a full-wave rectifier 10, and is smoothed by a smoothing capacitor 11, the electric power whereof is measured with a DC voltmeter 12 or is applied to the voltage coil of a wattmeter 7. The coil current flowing in the coil 1 is measured with an ammeter 6 and the voltage generated in the coil 8 is measured with a voltmeter 12. From the product of both measured values, the loss of electric power in the coil 1 is determined. It is also possible to read directly the loss of the electric power with the wattmeter 7. |
