Sherline DC Motor and Speed Control Unit*Special Order 3 4 Week Lead Time* About Sherline Motor and Speed Control Units The 90 volt DC motor provides far more than the 1 2 HP AC DC motor we offered before 1994. A DC motor provides its maximum torque at low RPM where you need it most, so the full speed horsepower rating of an AC DC motor can be a little deceiving as far as offering practical, usable power. The DC motor also offers a smoother and quieter operation. A more sophisticated speed