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When discussing this issue, we first need to clarify two concepts: one is the cell operating voltage, which refers to the voltage drop between the anode bus and the cathode bus of the electrolytic cell； The second is the pole pitch, which refers to the vertical distance between the anode and the cathode of the electrolyzer, that is, the vertical distance from the anode of the electrolyzer to the horizontal surface of the aluminum melt. Under identical external conditions such as the current intensity of the electrolyzer, the thickness of the anode insulation material, and the properties of the electrolyzer lining material, the operating voltage of the electrolyzer determines its thermal balance. That is, if the operating voltage is too high, it will lead to an increase in heat generation within the electrolyzer; the electrolyzer will enter a state of thermal expansion, the walls of the electrolyzer will thin out, the temperature of the electrolyte will rise, and its level will increase, all of which affect the normal operation of the electrolyzer and ultimately result in its failure ； Conversely, if the operating voltage is too low, the heat input to the electrolyzer decreases, the temperature of the electrolyte drops, the walls of the furnace thicken, the level of the electrolyte falls, the electrolyzer enters a cooling phase, more deposits form at the bottom of the furnace, the condition of the furnace deteriorates, and voltage fluctuations occur – all of which will ultimately lead to problems with the electrolyzer. Therefore, a reasonable pole pitch must be maintained. Among the various voltage drops that make up the operating voltage is the electrolyte voltage drop. Under conditions where factors such as current intensity, anode current density, and electrolyte conductivity remain constant, the distance between the electrodes directly determines the magnitude of this electrolyte voltage drop, thereby affecting the maintenance of the operating voltage. Therefore, the distance between the electrodes cannot be adjusted arbitrarily. A concept needs to be introduced here, namely the optimal pole distance. It refers to the pole distance at which an equilibrium is achieved among energy, materials, and voltage within the electrolyzer under normal temperature conditions and at the electrolyzer’s maximum production rate. At a reasonable pole distance, the electrolyzer has the lowest power consumption, the highest current efficiency, and the smallest various types of losses. It can be seen from this that the so-called \"high pole distance\" is not comprehensive enough; it would be more appropriate to call it a \"reasonable pole distance\". It is called a high pole distance because, with the advancement of aluminum industry technology, the molecular ratio of the electrolyzer, as well as the electrolysis temperature and the anode effect coefficient, gradually decrease. Under such conditions, it becomes very important to maintain a high pole distance, as this helps to preserve the normal thermal balance of the electrolyzer. However, if the pole distance is too high, this thermal balance can be disrupted. Therefore, in production, it is necessary to maintain a reasonable pole distance in order to ensure that the electrolyzer operates efficiently with low energy consumption. So how is the operating voltage and pole pitch determined in production? First, the operating voltage is determined by calculating the sum of the voltage drops across various parts of the electrolyzer ； Secondly, once the operating voltage is determined, an appropriate pole distance is set based on the molecular ratio and the temperature of the electrolyte; of course, the conditions at the bottom of the furnace are also a factor that needs to be taken into account. When the molecular ratio and electrolyte temperature decrease, it is necessary to increase the pole distance appropriately, that is, raise the operating voltage, in order to maintain a stable thermal equilibrium in the electrolyzer.