... . 3.Rated speed: 3000, 1500, 1000, 750, 600, 500, 400, 300 and 200 r/min, totally nine grades. Decrease armature voltage ... make speed regulating at constant output. Speed regulating range: See technical date. The torque can be remained constant by reducing speed ... with the voltage of less than 500V.5. Data listed in the technical data sheet should be employed under the following conditions; A ...