Main technical specifications 1. Recommended maximum oxygen flow: 5L/min. 2. Flow scope when the nominal pressure at the outlet is 7kPa: 0.5L/min～5L/min. 3. Apply 7kPa back pressure at the recommended maximum flow, the flow reaches accuracy of ± 10% to the indicated flow. 4. Oxygen concentration when the nominal pressure at the output is zero (achieve the required oxygen concentration level within 30 minutes of the initial startup): the oxygen yield is 0.5L/min to 3L/min, the oxygen concentration is ≥90%. 5. Output pressure: 0.02MPa～0.07MPa 6. See Figure 1 for function table of oxygen concentration and oxygen flow when the nominal pressure at the output is zero. 7. Release pressure of compressor’s safety valve: 280kPa±50kPa 8. Noise: ≤ 60dB(A) 9. Maximum nebulization rate: ≥ 0.1mL / min (for model with nebulizer) 10. Power supply voltage: 220V±22V/110V±11V, 50Hz/60Hz ±1Hz 11. Input power: 450VA 12. Net weight:     17Kg. 13. Dimensions:40×26×59.5(cm) 14. Altitude: the oxygen concentration will not be reduced when it is from sea level to 1828m, but the oxygen concentration will be less than 90% when it is from 1828m to 4000m 15. Safety system: ▲ Shutdown due to current overload or loose connections ▲ Shutdown due to high temperature of compressor; ▲ Low oxygen concentration alarm; 16. Shortest working hours: not less than 30 minutes. 17. Electrical classification: Class II equipment, type B application part 18. Running mode: continuous operation 19. Normal working environment ▲ Ambient temperature range: 5 ℃ to 40 ℃; ▲ Relative humidity range: ≤ 80%; ▲ Atmospheric pressure range: 860hPa to 1060hPa. Notice: When the storage and transportation temperature is below 5℃, the oxygen concentrator shall be placed in normal working temperature for more than 4 hours before operation. 20. Oxygen outlet temperature: ≤ 46℃ 21. Suggestion: the length of the oxygen tube shall not exceed 6 meters, and the oxygen tube can not be bent or deflated. 22. Storage and transportation environment: ▲ Ambient temperature range: -40℃～+70 ℃; ▲ Relative humidity range: 10% to 100%, and no condensation; ▲ Atmospheric pressure range: 860hPa to 1060hPa. Notice: The oxygen concentrator shall be stored inside the room where there is no strong sunlight, no corrosive gases but well ventilated. Do not shake or place upside down the oxygen concentrator during transportation.   List of packaging 1. oxygen concentrator      1 piece 2. disposable nasal oxygen tube      2 pieces 3. air filter      6 pieces 4. fuse   1 piece 5. remote control 1 piece 6. O-shaped sealing ring of humidifier     1 piece 7. Operation Instruction     1 copy   The oxygen concentrator with nebulizer is additionally provided with air pipe, nebulization medicine cup, nozzle or face mask.