Here is a pic. & description of how the 6V system works....
The white wire “feed” goes through the diode and then into the electrical system positive pole. The diode acts like a one way valve. Current cannot flow back through the diode so the only two possible places for the white wire current to flow is either into the battery or into the lights.
In the simple system, any excess current is burned up in the battery. In the zener system there is a third possible destination for white wire current. Any excess white wire current is burned off in the power resistor. Here is an explanation of current flow in the zener system.
motor off, lights off – No current flows.
motor off, lights on – Current flows from the battery to the lights.
motor running, lights off, battery fully charged – When white wire voltage is below the battery voltage, no current flows. When the white wire voltage rises above 6.8v, current is shunted through the power resistor.
motor running, lights off, battery below full – When the white wire voltage rises above the battery voltage, current flows into the battery to charge it.
motor running, lights on – Current flows from the battery to the lights. All white wire current flows to the lights. The white wire only flows current when it produces a voltage that is higher than the battery voltage.
A 35w bulb might be optimum for lighting up the road. But I too am going to look for a better compromise. My 6v generator headlight is just adequate so I still want to try an LED bulb of similar wattage. From reading other posts, the maximum wattage available from the white wire is about 5w. In my tests, I got considerably less. Even at the optimistic 5w maximum, the 35w light would require 7 hours of daylight driving for every hour of night driving. And you would need at least a 6ah battery to run the light for 1 hour continuously. The system could charge almost any size 6v lead acid battery but I think 6 to 8ah is about the practical limit.
I hope this explains it. If you have other questions let me know.
