I am looking at 3A and 10A PWM's on ebay. Which amp rating would be adequate to control a cordless drill motor, not sure of the voltage it originally used but it has sufficient power at 12V.

http://www.ebay.com/itm/New-DC-5V-4...076?pt=LH_DefaultDomain_0&hash=item3a7ed97e7c

http://www.ebay.com/itm/12V-40V-10A...441?pt=LH_DefaultDomain_0&hash=item48526fde59

Thanks

 

There's probably a wide variety of motors that will demand a wide variety of currents, especially when they are working hard. Also, if you stall them the current will get really high. All that is to say you will have to test the motor you plan to use to figure it out.