Armature voltage controlled DC drives provide constant torque.  They can deliver the rated motor torque at any speed between zero and the base speed of the motor.  Horsepower varies in direct proportion to speed.  Full rated horsepower is developed only at base speed.  Full motor torque is available from zero to 100 percent base speed


1/8 – 3 HP for Single-Phase Controls Indiana General   
Permanent Magnet Motors   


FOR 3-Phase Controls TEFC

For 3-Phase Controls
Open Drip Proof

Most Permanent Magnet (PM) motors were designed to be used with Silicon Controlled Rectifier (SCR) DC drives. With the advent of Pulse Width Modulated (PWM) drives, LIKE THE QDT SERIES, several things occur which allow the same motor to produce a higher Horse Power. This is a result of the form factor of a PWM drive being much less than that of a SCR DRIVE. The typical form factor for an SCR drive is 1.4 while the form factor for a PWM drives is less than 1.05. One of our Suppliers has prepared the following list of PM motors which we recommend when using our QDT series of drives. Notice the increase in horsepower when using PWM drives.