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Old 07-10-2014, 08:59 PM   #26 (permalink)
redpoint5
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Quote:
Originally Posted by serialk11r View Post
I think your current limiting resistor has too much resistance. 2C means it can take about 8A right? Drop it down to 0.1ohm and you'll get charge protection plus a more effective battery. I bet you can get away with even less than that.
I think you're right. I got the 0.2 ohm with worst case scenario in mind, where the voltage has dropped to 10v before starting, and then the alternator puts out 14.5v; a 4.5v difference. When the battery voltage is closer to alternator voltage, a smaller resistor can be used, and I bet 0.1 is ideal. Perhaps allowing a higher current when the battery has been more deeply discharged is still safe.

I do have 2x of the resistors, so I could wire them in parallel and that would give me the 0.1 ohm resistance you suggest. The results of which we already know. Double the charge and discharge current.

I'm almost tempted to try a 0.05 or even a 0.01 ohm resistor. Heck, Lasersaber didn't even use a limiter... then again he blew his battery jump starting his lawn mower.
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