Just now getting into lighting and have read several books and many hours on forums trying to learn what I can and am now giving it trial and error in the field. I just finished a system and have a question on my readings at fixtures. I have 3 different trans setup on the property but will just give you one scenario to see if I am correct on this. I have 4 runs on the one 600 wat trans and split them into approx. 100 watts per run on 12/2 with them installed in a loop runs back to trans. I have them set to 12v at the box and my nearest fixture to trans reads 11 and the furthest reads 10. Is the about right what I should expect in a voltage drop ont his run which is approx. 50-60 feet. House looks great at night and custoemr very happy but I am still learning and trying to understand.