An apparatus for electrostatically spraying a coating product. The apparatus includes a sprayer with first and second pipes which control the flow of the coating product. Air is controlled by at least one valve. The sprayer includes a device for controlling the opening/closing of the valve, a high voltage unit. A generator includes a module for controlling power supplied to the high voltage unit. The sprayer includes a first sensor suitable for detecting the position of a shutter of the valve relative to a seat and for outputting a signal used by the control module to control the power supplied to the high voltage unit, and a second sensor suitable for detecting the position of a switch positioned on the spray gun and for outputting a signal used by the control module to control the power supply of the high voltage unit.