... isolation transformer, RS232 Name : Online low frequency UPS power supplyModel NO.:FR-UK3120,FR-UK3130,FR- ... three phase in and single phase outPower Range : 20KVA, 30KVA, 40KVA, 50KVAApplication : computer room, data center, precision instrument ... indicates running statusAlarmLow battery, abnormal AC input, overload, UPS failureProtectionLow battery, overload, output over voltage, short-circuit, ...