Abstract: A control circuit is disclosed for limiting the polarity and duration of current flowing through an electromagnetic device which is coupled to an alternating current potential source. The control circuit is coupled in series with the electromagnetic device and a switch. The control circuit includes a gate controlled conduction device and circuitry which is utilized to selectively gate that device only during one positive half cycle following the closing of the switch. A second gate controlled conduction device is utilized to discharge a capacitor in timed relationship with the alternating current potential source and prevent recharging of that capacitor until the switch is opened and then closed again.

Abstract: Circuitry for providing high voltage DC power from commercially available 60 hertz AC utility power. The incoming 60 hertz AC voltage is rectified to a DC voltage. This DC voltage is then converted to a high frequency AC voltage by means of a sine wave inverter. This high frequency sine wave voltage is then converted to a different voltage and rectified by a voltage doubler. The inversion and rectification are under the control of logic circuitry which includes means for sensing line faults to provide circuit protection.