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Unread 31-01-2008, 22:43
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Re: Using Digital Output to control Brake/Coast on Victor

Quote:
Originally Posted by Jim E View Post
So having the brake set would mean the battery is drawing a large current into the motor in order to stop it's inertia if running full bore. The victor doesn't see the current path at all since the MOSFETs are short circuited(no damage) or do the Victors sink the excess current?

If the speed is great enough, then there exists the possibility to trip the 40A breakers when the brake is applied?
No, there is little or no current draw on the battery beyond what the cooling fan on top the victor draws. All that happens is both sides of the motor are tied to ground (bottom two mosfet triplets energized) which causes the motor's back EMF to fight the forward motion of the motor. Note i said EMF: this is what you have to watch out for. It won't pop breakers or anything, but just like a broad-spectrum low frequency RF emitter it'll induce currents in any surrounding signal wires.

-q
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