... price ST Series Single-phase synchronous alternator 1,safe,environment-friendly 2,brushless stamford alternator 3,competitive price SZN-184 Series Brushless Alternator/Generator/ Dynamo ... : 50 / 60Hz 4) Rated speed: 1,500 / 1,800rpm 5) Three-phase four-wire 6) Protection: I5P21- IP23 7) Insulation: Class H ...