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>
>just letting you know that my engine is nearly finished ! It has been
>rebuild with all new parts, so I hope it'll run better than ever before.
>Oh, yeah, one thing...I hereby repeat my question about the windshield wiper
>engine. How many amps does it need to work properly ? I need this info
>because I want to place a 12 to 6 volt converter in between the electrical
>system and the windshield wiper engine, because this thing is so difficult
>to replace and I don't have the time to take the dashbaoard apart. The notch
>is my only car, you see. And my mom is getting tired of me using her car all
>the time...
Tim,
The problem with the solution that you're asking for is that it's not a very
good one. To use a resistor, you need to know the current draw, but in the
case of a WW there is no good answer. The current will always depend on the
load, and the load depends on the weather conditions: dry, wet, very wet,
snow, or icy. This would be a very good application for a 7 V Zener, but
you will need a lot of amps, and 50 Watt Zeners were discontinued a decade
ago. Even 50 Watts might not be enough.
You could always design up a zener regulated power transistor series-pass
regulator that could handle over 100 watts, but that would mean that if you
wanted to run your wipers, you might be using 100 watts in the motor, 100
watts in the regulator, and your generator is only good for 300 watts or
less. That leaves very little headroom to run the car, headlights, etc.
You would be much better off finding an appropriate 12 unit. I know this is
extra work, but it will give you much more satisfaction in the end.
Sorry to be such a wet blanket.
Jim
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Melissa Kepner Jim Adney
jadney@vwtype3.org jadney@vwtype3.org
Laura Kepner-Adney
Madison, Wisconsin
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