I plan on building this PWM
http://www.rmcybernetics.com/project...controller.htm
PWMs can adjust the frequency and can adjust the pulse width and they are also used for limiting the amount of amps to the device.
What part of this PWM actually limits the amps? The schematic uses a 10Amp transistor, however I want the PWM to limit the current to 30amps. How would I go about limiting the current to 30amps? Would I have to get a 30amp transistor? Or could I get a 50amp transistor and somehow adjust it to limit the amps to 30?