A system for coating objects having: a) a coating booth in which the objects may be acted upon by coating material and through which an air stream can be guided which takes up overspray particles of the coating material and conveys them away; b) an electrostatically operating separating device whereof a housing has an inlet opening for the overspray-particle-laden air and an outlet opening for the cleaned air, wherein at least one separating electrode (25; 125), which has a separating surface, and a counter electrode device (26; 126) are arranged in the housing; c) a high voltage source, whereof the poles can be connected to the separating electrode (25; 125) and the counter electrode device; d) an air path for the overspray-particle-laden air, which leads from the base of the coating booth to the inlet opening of the separating device; wherein e) each separating electrode (25; 125) is associated with a supply device (80; 180) that enables separating fluid to be supplied to the upper region of each separating surface of the separating electrode (25; 125) in such a way that the separating fluid flows extensively over each separating surface of the separating electrode (25; 125); characterized in that f) the supply device (80; 180) has a supply channel (81; 181) which can be filled to a certain level with separating fluid and is formed in its lower region by two spring steel plates (84, 85; 184; 185) which resiliently lie at least sometimes and at least partially with their respective lower edges against opposite operating surfaces of the separating electrode (25; 125); g) two sliding plates (99, 100; 199, 200) are provided, which lie displaceably against opposite separating surfaces of the separating electrode (25; 125); h) an actuating device (103; 203) is provided, by means of which the sliding plates (99, 100; 199, 200) can be moved back and forth between a position in which their lower edges are located above the lower edges of the spring steel plates (84, 85; 184; 185) and a position in which their lower edges are located below the lower edges of the spring steel plates (84, 85; 184; 185). a) a coating booth in which the objects may be acted upon by coating material and through which an air stream can be guided which takes up overspray particles of the coating material and conveys them away; b) an electrostatically operating separating device whereof a housing has an inlet opening for the overspray-particle-laden air and an outlet opening for the cleaned air, wherein at least one separating electrode (25; 125), which has a separating surface, and a counter electrode device (26; 126) are arranged in the housing; c) a high voltage source, whereof the poles can be connected to the separating electrode (25; 125) and the counter electrode device; d) an air path for the overspray-particle-laden air, which leads from the base of the coating booth to the inlet opening of the separating device; e) each separating electrode (25; 125) is associated with a supply device (80; 180) that enables separating fluid to be supplied to the upper region of each separating surface of the separating electrode (25; 125) in such a way that the separating fluid flows extensively over each separating surface of the separating electrode (25; 125); f) the supply device (80; 180) has a supply channel (81; 181) which can be filled to a certain level with separating fluid and is formed in its lower region by two spring steel plates (84, 85; 184; 185) which resiliently lie at least sometimes and at least partially with their respective lower edges against opposite operating surfaces of the separating electrode (25; 125); g) two sliding plates (99, 100; 199, 200) are provided, which lie displaceably against opposite separating surfaces of the separating electrode (25; 125); h) an actuating device (103; 203) is provided, by means of which the sliding plates (99, 100; 199, 200) can be moved back and forth between a position in which their lower edges are located above the lower edges of the spring steel plates (84, 85; 184; 185) and a position in which their lower edges are located below the lower edges of the spring steel plates (84, 85; 184; 185).