I have a farberware percolator , 55cup, model 155A. It has a non removable plug in the base and a two prong plug in above it. I am missing the two prong plug in. Do I need both of these in use?? My bottom plug is freyed and needs replaced. I don't want to spend money on that if I need both plugs and am missing one. I called farberware. The item is too old and they no longer have parts or online owners manuals. The top plug is 3/4 spacing on the prongs.