I have a Hampton Bay low voltage tracking lighting system that uses a toroidal transformer to provide 12 VDC to the track rails. The system was purchased from Home Depot and has two sets of identifying numbers. The bar code reads: 73546 15055 and the SKU appears to be 447 909. The system comes with five 20-watt halogen lights (MR16) and says not to install any bulb rated higher than 20 watts. I can find no rating information on the transformer so I am uncertain if the transformer will support more than the five lights that come with the system. Thank you.

Most transformer will tell you the wattage in fine print on the plastic, hard to read but UL requires it. Most systems do not come with a transform larger than just what it needs, I'm guessing your transformer is rated just slightly above 100 watts.