Abstract: A method and apparatus for providing power to an electrostatic device includes a monitor and control system that prevents inadvertent and damaging electrical arcing. When the electrostatic device is first energized, voltage is gradually increased and the flow of electrical current is closely monitored. In the event the device is too close to ground or a grounded object, current flow exceeds a predetermined threshold and power is disconnected from the electrostatic device. Later, as the device voltage is increased to operating voltage, electrical current delivered to the electrostatic device is monitored for excessive current and excessive rate of change. If either fault condition is detected, power supply voltage may be reduced or disconnected, depending upon the severity of the fault. A microprocessor control system is illustrated for implementing the invention, including hardware and various software algorithms that provide the requisite gathering of information, analysis and responsive actions.

Abstract: A method and apparatus for controlling components used in the application of a coating incorporates digital communications and improved signal verification into the coating process. The method consist of sending data from one or more controllers to a controlled device, such as an electrostatic power supply, turbine speed controller or other coating device, and receiving data therefrom over a digital data link. The data sent to the controlled device may include any control parameters, including activating the controlled device to perform an intended function or instructions that tell the controlled device what to do. The data which may be returned from the controlled device includes various status information. Where the controlled device is a power supply, the method further incorporates a cross-checking function, to prevent accidental activation. The coating apparatus includes a device for spraying a paint, powder, or other type of coating in a controlled manner onto a receiving surface.