The value has nothing to do with the total oil capacity, google TOG sensor or VW oil level sensor and you will see a picture of a black plastic rod tat comes off the bottom of a metal housing that bolts into your sump, the black plastic sticks up into the oil and measures the oil temp and the oil level.
The sensor tells you the amount of oil as a level above the base of the sump, when your engine isnt running it will all be sat in the bottom which is the total level you will see. Then when you start it up it will circulate around the engine and under normal conditions and at varying viscosities you have an amount in the sump that isnt being pumped around the engine so think of the value as ex number of units of oil level in the sump.
So the minimum figure I think is what will set off the oil level warning and the actual figure is the current value.
