“R” indicates that the FXR was designed for renewable applications. Off-grid and grid-interactive functions are integrated in the same inverter.

Vented models are preceded with “V”, as in “VFXR3648A”. If a model number does not begin with “V”, it is a sealed model and is equipped with a Turbo Fan.

The first two digits show the power of that model. For example, “FXR2012A” is 2000 watts.

The second pair of digits shows the inverter’s nominal DC voltage. For example, “FXR2524A” is 24 volts.

The model number is followed by “A”. This designates the inverter’s output as nominally 120 Vac (used in North America, Latin America, Asia, and other regions).