The invention is intended for the organization of an automated process for spraying of liquid means of chemical treatment from unmanned vehicles, for example, in precise farming systems. The use of a replaceable, marked and hermetically sealed liquid subsystem in the spray device of the invention, along with an integrated self-diagnosis system, using compressed gas energy and a pressure regulator instead of standard pumps, reduces the weight of the spraying device, improves spraying accuracy, ensures personnel safety and accounting of the accumulated life resource of the main units of spraying devices. All this in combination enables to create fully automated spraying systems.