A zener diode is not the same as a recifier diode. Think of the zener diode (Z1) as a “pressure relief valve”. When the voltage (pressure) reaches 6.8v, the zener bleeds off the excess pressure through the resistor (R1). It protects the battery from overcharging. If you do not have a battery in your system, you could use just the zener regulator to protect other voltage sensitive components such as led lights.
No revisions at this time. At least not for my implementation. There are at least a couple of people that have done successful implementations of the 6v negative ground charging system. That includes me. I have a little less than 500 miles of use so far. I use the brake light regularly. The headlight is only used on occasion. The battery is staying fully charged.thanks again... i am eager to try this out, if there are any revisions in your plans please keep us up to date.
I’m back. I’m assuming that you have a 6v battery being charged by the white wire through the rectifier diode. The first thing to sort out is the charging system. How big is the battery? What kind is it? Do you have a digital voltmeter to test things? Leave your lights disconnected for now. Check your resting battery voltage with the voltmeter and write it down. Ride your bike for several miles. Check your battery voltage again. Or you can check it while reving the motor. It should be slightly higher immediately after riding or when reving the motor. If so, the charging system is working. If not, you need to find the problem. Now make sure your 6v lighting system is working. Turn on the headlight switch. Does the headlight work? Try the brake/tail lights. Do they work? If not, try reversing the polarity since most LED lights are polarity dependent. What is the operating voltage of the 3w chip LED? All components will need to be in the 6v range to work with this system.
Use 6v components when possible and wire everything in parallel. I originally used a 6v automotive bulb but switched to a 6v led bulb from superbrightleds.com. The tail/stop bulb that I use is their 1157-W19-6V. They have other bulbs including single filament that you may be able to use. The creexre-w100 is rated at 3.3v and 350ma. So it should be about 9 or 10 ohms. Put a 9 or 10 ohm 2w resistor in series with it and it should be OK with the 6 volt battery. You could use a 5 or 6 ohm resistor without exceeding the maximum allowable drive current (double check the math). That would give a brighter LED but possibly reduced life. Put the series resistor/LED combo in parallel with your other lights.
Nimh batteries may be more sensitive to charging variables than lead acid batteries. Let me know how they work out.
If you plan on using a 6v system; Put a 10ohm resistor in series with that particular 3.3v Cree LED or run two of the Cree 3.3v LEDs in series. If you run two in series, you will get more light and won’t be wasting energy through a resistor.
That is exactly what you should do. Unless you know a little about ohms law, keep it simple and just make sure you use 6v rated components. The tail/brake is easy – use a 1157-W19-6V bulb from superbrightleds.also im curious,parallel? series? resistors? is there anyway just to get LED headlight and brake light and wire it straight up,headlight negative=ground, positive=pos battery,then taillight on its own circuit separate from the headlight? maybe someone can walk me thru what other parts i need to set up the lighting system, the charging system schematic doesn't seem to be that hard to follow.
thanks for the help
That looks like a good choice when using an LED of different voltage than your battery. More efficient but more expensive than a resistor.
