... volume,lower noise,high reliability*double isolation of the input and output ,safe and reliable*output the pure sine ... Reactime:≤2msDigital meter indication:Frequency,voltage,current,power and power factor meterWorking temperarure:-28°C-60° ... Altitude:1500mprotection:Overcurrent, overvoltage, overheat,overload protection and automatic warning devicescooling system:Forced fan cooling 3KVA 400HZ frequency ...