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Old 12-17-2008, 10:28 PM   #14 (permalink)
MPaulHolmes
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Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
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Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
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Today was pretty productive. First, it snowed a whole bunch! It doesn't snow that much around here, so it's been really cool. It's late now, and the sky is bright pink. Weird!

The EVTech list has been really, really helpful. For the car's version of the controller, 4 ounce copper pcb is required. That stuff is sort of hard to come by at your local radio shack. What it means is that every square foot of the pcb (printed circuit board) has 4 ounces of pure copper on it. That's a lot! Someone on the EVTech list is sending my wife and me 2 pcb's of 5 OUNCE copper for free!!! That's thick!

The bike version of the controller will be able to handle around 40 amps. So, there has to be a copper bus on which all the current flows. Each mosfet will contribute about 8 - 10 amps to the bus. Such a high current requires pretty heavy copper. I'm thinking of using 10 gauge wire for the bus.

So, here's the rub. How do you solder a lead (leed) from a mosfet to such a heavy wire that will be about 6 or 7 inches long? Try it! Take a soldering iron and try it! It's tough. The dang wire won't heat up enough. So, 2 days and many EVTech.org conversations and reading and trying several things that don't work led to an awesome solution! But that's for another update... I just heard the doorbell ring...

HOLD EVERYTHING!!! WHO COULD BE VISITING IN THIS SNOW STORM? ONLY THE UPS MAN!!!!!!!!! That's right! The programmer and 2 microcontrollers (atmega8) just arrived! heck ya dude! This is where things get interesting...

Oh no! It's a static sensitive device? I need a static free workstation! Hmm... What to do? hahaha!
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