A method is provided for isolating an electrostatic sprayer from an electrically grounded coating product distribution circuit connected thereto. The method includes spraying an electrically conductive coating product, such as water-based paint, from an electrostatic sprayer onto a workpiece passing in adjacent proximity thereby, on command, the sprayer being carried by a maneuverable robot arm. The coating product is supplied from a remote source of supply through at least one distribution circuit connected to the sprayer, the robot arm also carrying an electrically insulative storage tank for the coating product connected to and positioned downstream within the circuit from a length of electrically insulative conduit. This insulative conduit includes a cleaning mechanism for cleaning a portion, including all, of the length of conduit, in situ, after filling of the storage tank with coating product and before spraying. The length of conduit is wiped clean on command, thereby galvanically isolating the sprayer from the supply source and distribution circuit during the spraying operation.