Ns = 120*f/P = 120*60/4 = 1800 rpm
S% = (Ns-Nr)/Ns*100% = (1800-1746)/1800 *100% = 3%
35 一台 10 kW,4 極,60 Hz 之三相感應電動機,滿載轉速為 174..-阿摩線上測驗