Grower's Choice Digital Lighting Master ControllerMaster controller is available to control two lighting groups in a greenhouse. Output 0 11. 5v adjustable DC voltage to control ballast output power or switch on off the ballast. The controller operates on a 24 hour time cycle. The controller also has the ability to simulate sunrise and sunset cycle from 10 60 minutes. Each of the two lighting group channels has a room overheat protection function that can be set as needed. You can use the LCD