RK series PK20S-AU 50 Hz @ 1500rpm,1-phase/3-wiring 1 Standards & Conditions • • • • • • • • ATS (automatic transfer switch) receptacle Dry type air filter Environmental Operating Conditions • • • • • • Installation place: Outdoors or indoors (well ventilated). Ambient temperature: -25℃ to 45℃.The coolant heater is needed when the temperature is below 5℃ 3 Equipment Specification • • Humidity: Less than 90%.