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Old 09-10-2010, 11:54 AM   #3745 (permalink)
Master EcoModder
Join Date: Apr 2009
Location: Charlton MA, USA
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EVVette - '71 Chevy Corvette Coupe
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OK, I will make this the simplest explanation there is. lol

Have you ever turned off the faucet really fast after running the water full blast? When you do this the pipes bang. Same thing. Its the water abruptly coming to a stop.

This the just what happens with the voltage when you turn off during each cycle of the pwm. The voltage spikes and smash's into the closed gate of the mosfet. The diode is basically a pressure release that allows the voltage to flow back into the battery and not pound the mosfet to death.

__________________ - 1971 Corvette Coupe Conversion to all Electric! - Machining, CNC, Robotics and Electronics.

You can download RTD Explorer for the Cougar controllers at
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