Glen-L.com

Trackhappy Thanks for the info I will try radio shack and do a temporary install and see if it gets super hot.Now when I go up to the counter I might sound like I know What I am talking about. The last guy at the electronics warehouse was not a car guy had no notion what I was trying to accomplish.

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) Champagne dreams and wishes are possible on a beer budget. Just build the boat.
Nice curves are easy on the eyes.
Go sell crazy somewhere else we're all stocked up here."As Good As It Gets" Jack Nicholson.

Last word, every boater should have the things he wants on his boat and if you want that light you should have it. The talk about volt meters and amp meters are just suggestions to accept or discard, your choice. To go back to your original question I don't think the resistor value is critical, the low value is used so that most of the generated current goes into the system but you have to have the resistor in order to get the light to operate. The wattage in this application is the critical item. The value that you stated is probably correct. Wattage should be in excess of the maximum expected and can be determined by multiplying the output volts times the output ampere hours. These can be supplied by the maker of the alternator.

Nicely said jcallands!

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Bill

I told my wife we needed a three-car garage for my projects...she told me to ask her for permission next time before I buy a house.
http://www.unitybuild.net

He has a 3-wire, it needs a ballast resistor paralleling the bulb to bleed down the voltage, or the light is always on dimly, and if the light fails, it looses output.
The exciter lead needs some resistance. If it is at full 13.8V it defeats the remote sense function, and can cause some ignitions (msd in my experience) to run on. I assumed it was a result of the field being excited backwards, through the sense lead. (could be way off, never really tracked the cause down. Replacing the light, and ballast fixed problem.)

The system will operate fine without the resistor.

The resistor is made to shunt the bulb in the event of a filliament failure, and keep the system running. If you don't have a resistor, and the bulb opens, the charging continues as long as the engine is running, but next time you start it, you will have no field startup in the alternator, and no charging.


Be sure you use the correct bulb, the resistor value changes with the resistance of the bulb. #57 lamp needs a 25 ohm-5 watt (in my experience) Use a wire wound, metallic film is not going to hold up. http://www.parts-express.com/pe/pshowde ... ber=015-15 Shipping is going to be more than the part.

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Some plan to stroll through Saint Peter's Gates, I plan to go through them at 150mph... backwards... in a screaming ball of flame, with a glimmer belt wrapped around my head, and a NOx button in my hand.

I know the light at the end of the tunnel is off, but sure glad you found your way back to this forum. Thanks for the info. Have not yet bought the ballast resistor but plan on doing so now and especially since I am running a MSD ignition.

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) Champagne dreams and wishes are possible on a beer budget. Just build the boat.
Nice curves are easy on the eyes.
Go sell crazy somewhere else we're all stocked up here."As Good As It Gets" Jack Nicholson.