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Unread 13-01-2003, 15:03
DanL DanL is offline
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hmm... one of my electrical mentors explained it to me like this the other day.

At 6 volts, the voltage drop we want is 1.2 volts. 1.2v / .18 amps gets a resistance of 6.6ohms. But, if we rearrange the equation for Voltage, then E = R * I. Therefore, at idle current, the voltage drop becomes 6.6 * .007 = .046 volts. So basically, using just a simple resistor is fine when you're running it, but when it's idle, you're still essentially shooting out the whole 7.2 volts.

Now all of you are saying that it's fine to overload the servos. Thats okay, but our mentor-guy came up with a neat little circuit that keeps the voltage between 3 and 5volts. So if anyone ever wants to run two servo's out of the edubot and feel like teaching a bit about electricity, here ya go.
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Dan L
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Software Engineer, Vecna Technologies