It's not volts, but amps, Ryan, as you probably have suspected. The volts thing is confusing.
Basically, look at this way: volts is a measure of electrical PRESSURE, and amps is a measure of electrical FLOW. If you have a tank of water, and you look at the pressure at the bottom, you have pressure but no flow. Put a valve on, the valve "sees" the pressure, but until you turn it on, there is no flow.
LED's WILL eventually draw a battery down. The 0.020 amps of drain or so per LED is small, but enough of them, or leave them on long enough and it can have an effect. For most of us that start and run our vehicles fairly often, it's not a real problem
LED's in series are most efficient! 3 LED's run in series still only draws 0.020 amps. It's not a contradiction. In the single LED circuit you were wasting most of the power in the resistor. In the multiple LED circuit the resistor does less and the power you would have wasted instead lights additional LED's.
Power, by the way, is volts times amps. It's the measure of actual work being done. In our "typical" LED case, 12 x 0.020 = 0.24 watts or about a 1/4 watt of power total.
Hope that helps a bit, and ask for further clarification as required.
Last edited by n3elz; 12-15-2004 at 12:01 AM.