Patent ID: 8048286

Claim:
A method of taking an inoperative pot online using a fuse in an aluminium manufacturing plant operating on an electrolysis process wherein the manufacturing plant comprises of plurality of electrolysis pots, the pots being provided with risers that are electrically connected to anodes, and cathodes that are electrically connected to cathode bus bars; wherein the anodes and cathodes are submerged in a bath formed by electrolyte and ore, and voltage across an individual pot is within the range of approximately 4.2V to 4.3V; and electric current in the range of about 320 kA to 324 kA is passed through the pots through the risers, the current passing through the bath to the cathodes, the electrodes of the plurality of pots being electrically connected in series, with some of the pots being kept off line during start up of the manufacturing plant by shorting the risers of the non running pots to the cathode bus bar by shorted joints (II), thus bypassing the current through the non running pot and connecting directly the adjacent pots on either side of the non running pot, the method comprising following actions being carried out on the non running pot: a. fitting fuse assemblies in parallel with the shorted joints to connect the risers to the short circuit bus bars on both sides through the fuse assemblies; b. opening the shorted joints; c. inserting insulating insert plates between the risers and the short circuit bus bars and securing the short circuit bus bars in place, thereby isolating the short circuit bus bars from risers; d. passing a full load of current of the short circuit bus bars through the fuse assemblies; e. melting the fuse elements in the fuse assemblies within about 8 to 10 minutes at the rated current in the shorted bus bars, thereby isolating the short circuit bus bars completely from the risers; f. feeding current from the risers to the anode assemblies of the pot through the anode bus bars; and g. feeding of the charge to the bath in the pot is started, thus taking the non running pot on line.