If you have decided to use a HVLA (High Voltage/Low Amperage) configuration, then things get even simpler.
Of course, verify your supply voltage with a good electrical meter. Let's use 110 volts (typical wall voltage) as our supply this time.
We will refer to RMS(Root Mean Square) voltage, rather than actual voltage, because wall current varies. Also, we are assuming you have built a good bridge rectified power supply that plugs into the wall for power.
Electrolysis won't occur with Alternating Current. You need Direct Current.
If we divide the 110 volts by the desired 2.4v Plate Gap Voltage then you get 46 plates (rounded up from 45.83). You would need a total of 46 plates for this cell configuration. Here are some configurations for a cell using HVLA 110 volts and a Plate Gap Voltage of 2.4v:
1 Cell w/ 46 plates: - (44 neutrals ) +
2 Cells w/ 100 plates: - (44 neutrals) + (44 Neutrals) -
Remember, that production depends a great deal on the surface area of the electrodes. With a cell this large, even a little amperage can produce large quantities of HHO. Make sure you have a well developed.