I have a couple mechanical timers and was surprised to see that neither of them actually turn off the power when the switch off. I was going to flip some plants and decided to make sure I had the light set properly. When I looked in the tent to make sure it was off I noticed a little glow. When the switch is on it measures 120V AC, but when it is off it measured 26V AC not zero. I tried the other timer and it measured 16V AC. Argh! Do all mechanical timers work this way or are these two broken? Should I be using a different timer?