The invention relates to a valve assembly (30) for a spray machine (10), in particular for agricultural machines (12) or self-propelled plant protection devices, comprising a first valve that can control a flow volume of a spraying product (20) according to a valve position, a first electrically operated actuator (40) for setting the valve position and an energy store (78) that provides electrical energy for operating the actuator (40). The valve assembly (30) further has a charging circuit (102) for charging the energy store (78) and a control and evaluation unit (80). The control and evaluation unit (80) is configured to control a charging operation of the energy store (78) so that a charging time and a charge build-up of the energy store (78) are linear to each other.
