A device for ion charging airborne toner particles for the development of electrophotographic images is proposed. The electric motor includes a rotor and a stator assembly. The housing defines openings to contain cables extending therethrough, each opening having a first and a second portion each configured to contain cables extending therethrough and a passage portion extending between the first and second opening portions and configured to allow passing of at least one cable between the first and second portions. The valves are configured such that when the electrical control signal is absent or the electrically controlled valve is unresponsive thereto, the presence of pressurized fluid at a predetermined supply pressure, will automatically operate the pilot operated valve in cooperation with a biasing element thereof, for delivering pressurized fluid at a minimum or reduced regulated pressure. As a result, an OFF-state leakage current which flows between, for example, the gate electrode and sourcedrain regions is suppressed and a manufacturing process suitable for actual mass production is established.