Severe-duty a.c. motors with 75–800-hp output
The Simotics SD200 severe-duty motor in frame size 440 (photo) provides high productivity and energy-efficient operation in all torque ranges. These new cast-iron NEMA motors are built to power pumps, fans, compressors, hoists, winders and similar equipment in harsh environments. With a three-year warranty, the SD200 motors offer 75–800-hp output and feature 444-5013 cast-iron frames for operation in 460 and 575 V ranges. They meet or exceed NEMA Premium MG1 Table 12-12 efficiencies. A wide selection of options is offered, including IP56 ingress protection, encoders, brakes and blowers, plus others to suit the applications presented. On these motors, the frame, end-shields, fan guard and easy-access, diagonally split, oversized terminal box are all cast-iron. Complementing this construction are zinc-plated hardware, epoxy paint and stainless-steel nameplates for long life and easy identification in the field. A unique offset rotor bar provides improved efficiency, while larger bars and end rings reduce resistance. Each die-cast aluminum rotor assembly is dynamically balanced for extended bearing life and includes a high-strength C1045 carbon-steel shaft for maximum performance. — Siemens USA, St. Paul, Minn.