Button A Dimmer button. How to use it?

[84germain]

Hello.
I've the SL2048FC.
I fund this explanation in the online manual:
Button A
Dimmer button. Keep this button pressed simultaneously with the [ + ] or [ - ] buttons to dim in or out from a preprogrammed scene.

But that all and I don't understand what to do. Should I configure something in ESA before write in the memory or this button is enabled on all scene?

Thanks

[bruno.falip]

This button is a master dimmer, it is available for all scenes.