Abstract: Methods for control and protection of anode assemblies in mercury cathode cells for the electrolysis of alkali metal and alkaline earth metal chlorides so as to provide commands or an alarm when the load on an anode assembly exceeds a predetermined level so that the anode assembly or assemblies can be raised, the determination being made by comparing the difference between the load for each assembly and the mean of all assemblies with a predetermined upper level, and also desirably comparing the difference with a preselected lower level and determining the electrolysis voltage and comparing it with a desired lower electrolysis voltage to provide a command for lowering the anode assembly or assemblies involved, generally with a delay in the lowering command and with the raising of the anode assemblies taking precedence over the lowering thereof.