If you are adhering to an LVHA (Low Voltage/High Amperage) configuration, then you will first want to determine your desired Plate Gap Voltage.
Then, verify your supply voltage with a good electrical meter.
We will use 13.6 volts supply (typical automotive battery) as an example.
Divide the supply by what you want your Plate Gap Voltage to be. Let's say we want our Plate Gap Voltage to be 2.4 volts.
You should get a total of 6 (rounded up from 5.7) plates per complete cell.
This means your single cell configuration would be as follows:
+ N N N N -
If you wanted more than one cell in your configuration then you would have the following configurations:
2 cells: - NNNN + NNNN -
3 cells: - NNNN + NNNN - NNNN +
4 cells: - NNNN + NNNN - NNNN + NNNN -
You could continue adding cells accordingly as long as your supply voltage was 13.6 volts and still maintain your desired 2.4 volt Plate Gap Voltage! Because HHO production depends on the total amount of surface area within the total cell, the more HHO you can produce.