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Old 03-28-2012, 03:14 PM   #54 (permalink)
mort
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Quote:
Originally Posted by mechman600 View Post
Can I assume 12.6V/1.1 ohms = 11.4A, or does an inductive resistance change when there is current?
Hi mechman,
About 12 amps is probably the maximum you can expect using a 12 volt battery. Your question is a doozy though. The current through an inductor takes time to build, like spinning up a flywheel. The time depends on the amount of energy the inductor can store. Like a heavier flywheel is harder to spin, in a bigger inductor it is harder to build up current. This is like resistance, it is a complex number called impedance (it has a real component and an imaginary component) and it varies with the rate of change of the current. Worse, this is a field coil in a motor and as the motor runs the field experiences changing magnetic influence from the rotor. So current and voltage associated with that coil gets pretty messy. But the maximum current that the diode will carry is about the battery voltage divided by the coil resistance.
Quote:
Originally Posted by mechman600 View Post
Since all these cheaper diodes come in packs of 10, maybe I will hook them all up together to make one strong diode. Add some redundancy to it at the same time!
Aa MPaulHolmes said, diodes don't share well.

-mort
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