I have several sets of ACI Ionbeams..The 16" full spectrum bars and 11" UV bars.
Each set will come with a little controller that will plug into the driver. The controller works as a timer and dimmer.
The light system can also plug into any of the ACI controllers that control environment along with light scheduling.
They can also be ran as "dumb" lights. They will be at max power and use an external timer like most older grow lights.
Given their output, dumb is the best option IMO. I run mine off an old analog timer. The controllers just make things confusing and over engineered.
These lights for the most part are like seedling lights, old 2' T5HO or 50 watt CFL type of output and performance, so there's no real need to ever dim them down.