... intelligent charging control to recharging timeLED,LCD display, audible and visual alarmBuild-in with big charger RT series long back up ... Protection15V15V30V30VDisplayLCDUPS Status, Input/output Voltage and Frequency, Load, AC,battery ,fault, etcOperating EnvironmentTemperature0°C~40°CHumidity5%~95%(<40°C,no condensation ...