Abstract: A coating system includes a source of electrically non-insulative coating material, a dispenser for dispensing the coating material toward an article to be coated thereby, and an electrostatic high potential supply for supplying charge to the coating material. The high potential supply is coupled across the dispenser and the article. The coating system further includes a reservoir, a valve having a housing providing first, second, third and fourth ports, and a component movable within the housing and having a first passageway selectively to connect the first port to the second port to permit the flow of coating material between the first port and the second port.

Abstract: A valve has a housing and a component movable within the housing. The housing has first, second and third ports formed in it. The movable component has a first passageway formed in it. Movement of the movable component within the housing selectively connects the first port through the first passageway to the second port, or the second port through the first passageway to the third port. At least one of the first and second ports includes a first member for contacting the movable valve component and a second member for retaining the first member. The second member may be constructed from a semiconductive material. At least a region of the movable component around a first end of the first passageway may be semiconductive.