Figure 1, click to enlarge. PSC MOTOR CURVE: A PSC motor curve showing the wide variations in airflow that occur related to changes in static pressure. (Courtesy of cfm Distributors The ECM 2.3 ...

Unlike PSC motors, ECM’s require integrated electronic circuitry and variable ... and its potential for cost-savings. The Energy Rating label provides a comparison based on the relative energy usage ...

Motors are also sometimes damaged after being exposed to water. “We replace a PSC with an ECM about 25 percent of the time,” Knight said. “We are seeing this percentage increase as customers become ...