... phase, PID Control Function , Up to 25 fault protections ,Automatic Voltage Regulation (AVR) Function ,multi-step speed , multiple torque setting source ... (protected from corrosive gases and dust)Ambient temperature-10~40°C(If beyond the allowable degree,one degree will Derogate 5 ... .2G)Protection rateIP20 2013 New Sensorless Vector Control Inverter,B504 Variable Speed Drive !