Improvements relating to electric arc furnaces

摘要

545,777. Automatic control systems for arc furnaces. ELECTRIC FURNACE CO., Ltd., SPANSWICK, J. R., and KING, S. G. May 24, 1940, No. 9195. [Class 38 (iv)] A voltage relay 11 controlling the adjustment of electrodes in an arc furnace 1 has a correcting voltage in proportion to furnace current injected by a transformer 26 so that the influence of the potential drop in the electrodes may be eliminated. The transformer primary may be connected across a conductor 10 or in series with the primary winding of a relay transformer 20, as at 31. The transformer 20 is adjusted by a mechanical connection 18 with the means 9 whereby the voltage applied to the furnace is determined. The switch 22 may be independently adjustable. The transformer 26 may have tappings to adjust the compensation.