I see that Maretron’s DSM150, DSM200, and DSM250 displays have a TLA100 configuration setting called "Tank Levels Calibration..."; what is this?

Maretron's DSM150, DSM200 and DSM250 displays have a TLA100 configuration setting called "Tank Levels Calibration:", which is used to program the type of sensor (American or European standard) that is connected to the TLA100. This setting can also be used to create a custom calibration for non-standard resistive tank sensors or irregularly shaped tanks.