480w is a lot of flexwatt. I have a 5 tier rack that runs under 60w are you sure you have calculated it correctly? 480w is not an accident if you check the specs on flexwatt it is the max amount of wattage that they recommend for the 3 inch 4 inch is 480w, the 11 is a touch more at 500 as is the 17 but that is 50 feet of 17 and 25 feet of 11.