Generally speaking if your turbine has larger than a 10 foot rotor diameter and or is rated for 2.5KW or more you may need more than one clipper. Please consult tech supportThe MidNite Clipper is designed to control Wind or Hydro turbines and work with the Classic to charge your battery. The Clipper communicates with the Classic to slow the turbine when the batteries are full, and also contains a stand alone self powered adjustable max VOC limiting circuit. The DC Clipper is designed to work with DC turbines and was designed for 3-4kw maximum turbines. The DC Clipper comes standard with 3.0 ohms of resistance per phase.