Abstract: In the electrostatic coating of workpieces with a coating installation in which material sprayed from a grounded rotary sprayer is electrically charged in the corona-discharge area by external electrodes inducing a corona-current to the sprayed material, the danger of the spraying device coating itself is reduced if the corona-current is adjusted to a predetermined value.

Abstract: In the electrostatic coating of large workpieces, for example vehicle bodies, the installation must be switched off automatically in order to avoid a voltage breakdown when the operating current rises to a threshold value predetermined as a function of the operating voltage which is adjustable over a certain range. To this end, all threshold values applicable to selectable voltage values are stored jointly, more particularly in a microprocessor, and when the installation is in operation, they are selected automatically according to the voltage which has been adjusted. A warning signal is produced when an intermediate threshold value of the current is exceeded, where the intermediate value has been automatically adjusted between the normal and threshold values of the current.