ES368664A1 - Automatic optimal setting of the electrode spacing of electrolytic cells. - Google Patents

Abstract

A control arrangement for a large number of electrolytic cells 2 comprises an electronic scanning device 3 connected to the cells through D. C. transformers 4 and feeding a central control unit 1 through an analogue to digital converter 5. The unit 1 takes the form of a digitally-operated data processing device which is programmed to control an order distributer 6 which in turn transmits signals to the electrode setting members 7 for the cells 2, so that the electrode spacing of each cell is maintained at an optimal setting (according to the cell voltage sensed by the transformer 4) or is altered to eliminate short circuit conditions. Members 7 may comprise relay controlled reversible motors and, as shown in Fig.2, selector relays 12 control respective groups of setting gears driven by motors 11 whose direction of rotation is determined by energization of one or other of relays 13, 14. The condition of the relay contacts is monitored by the unit 1 through another electronic scanning device 15, to stop the transmission of setting orders in the event of a relay fault. The distributer 6 may comprise addressable, bi-stable electronic switching stages each associated with a relay 12 and the relay 13 or 14, so that a setting operation lasts for a predetermined time determined by the unit 1. To ensure termination of setting in the event of a fault in the unit 1, the stages associated with relays 13, 14 may be monostable and dependent on pulses from the unit 1 indicative of its condition (correct or faulty). An independent time switch stage 16 also monitors the condition of the unit 1 and, in the event of a fault therein, automatically increases the electrode spacing of all of the cells 2 to prevent short circuits during the inoperative period of the unit 1. The stage 16 may also be used for remote manual control of the electrode settings.