Abstract: A method and device for varying a d.c. voltage connected to an electrostatic dust separator so as to render more effective, in return for a low consumption of energy, the collection of dust on an electrode or electrodes incorporated in the dust separator. The d.c. voltage is set to a first level (basic level), said level having superimposed on it a number, in each case two or more, of voltage pulses forming a pulse group, with the consecutive pulse groups being separated from each other in a time sequence and supplied to electrodes incorporated in the dust separator.

Abstract: A system and method for controlling energy input to a series of electrostatic dust separator devices having a common gas inlet and a common gas outlet. A detector unit is disposed in the gas outlet to detect the dust concentration or evaluate the actual dust loss in the exhausted gas. Energy control circuitry is coupled with each separator device to control the energy input to each separator device. The control circuitry is actuated by an actuating device to first change and then restore the energy input to each of the separator devices in a selected sequence to thereby change and restore the dust concentration in the exhausted gas. Computation circuitry is coupled with the detector unit to compute the change in dust concentration resulting from a certain change in energy input to each of the separator devices in the sequence.

Abstract: A control device for an electrostatic dust separator (10,11) intended to control in relation to the recorded level of direct current (104) and direct current voltage (102) in the dust separator and with the help of the supply voltage (6a) passes through the zero point the switching in and/or out of the rectifiers (8, 8a) wired into the power supply lead (6a) to the dust separator, usually in the form of two thryistors. The recorded value for the current (104) and the recorded value for the voltage (102) together with the information in respect of the passage through zero of the supply voltage (100) are connected directly via conversion circuits (25, 26) to a data processing unit (112).