OTHER SUPERIOR PRODUCTS

Because the 1% speed gain equates to a 3% horsepower requirement, they reason, the replacement energyefficient motor may have to be 1 HP-size larger than the standard motor. The contention does not fully account for the fact that the power reduction from using an energyefficient motor is greater than the extra power required by the load - hence, there is a net energy savings and the motor will run cooler, potentially extending insulation life. Design NEMA MG 1 (1987), Section MG 1-1.16, defines "design," which defines the torque and current characteristics of the motor. Letters are assigned the defined categories. Most motors are Design B,. although the standard also defines Designs A, C, and D. Common headings on nameplates include "Des," "NEMA Design," and "Design." Some motors may not conform to any torque-current characteristics defined in MG 1. The motor manufacturer may assign them a letter that is not a defined industry standard. It is important to check the design letter when replacing a motor in an existing application. Another note on Design B: Design B constrains the motor designer to limit inrush current to established standards. This insures that the user's motor-starting devices are suitable. A Design A motor has torque characteristics similar to those of the Design B motor, but there is no limit on starting inrush current. This may cause starter sizing problems. You should be aware of th