... can be used for:1) 1 ballast to run 2 lamps A & B, 1 on and 1 off at a time, ... lamps A & B and C & D, 2 on and 2 off at a time, controlled by built ... usage for 4 lamps, can run up to 10 amps for each ballast.Switch Box has many ... ballast, and then switching back and forth between 2 lights periodically, so that the grow room ... 3) Can be used to save money by 1/2 the number of ballasts used. Since one ballast ...