If it were just a switch you would be right, but the switch has the very inadequate 5 watt resistors on board. If you do not put the reducer between the Ignition Positive and the BAT terminal of the switch, you will not be giving those resistors the necessary Wattage drop that is necessary for them to run cool enough to not burn up. We talk about current and ohms a lot but we forget the Power formula. At least that's the last thing I think about.
The switch was made for 6 volt input so they put 5 watt resistors when 12 volts can generate as much as 14 watts. The flow from neg to pos is a given. But when the electrons hit that reducer is when the electrons slow down and voltage is reduced. This isn't my idea, its how it works on the bench. Hook it up both ways and watch what happens for yourself. If you still think it works the way you describe, I will be more than happy to change all of the text I have written on the subject after what I thought were thorough bench tests.
Hooked up with the reducer after the switch will get you about 100 degrees hotter on the resistors. They will last for a few years that way because of the sporadic way we use the switch, but those resistors are slowly dying.
Edit: I am not infallible. In fact, I have to stop and think before putting a diode in a circuit to remember which way it goes! Getting older sucks!
Last edited by Deve; 10/05/2015 3:20 PM. Reason: last para
