... Acid, Maintenance-freeDC Voltage36VDC96VDC240VDCCapacity12V/7AH*312V/6AH*812V/7AH*812V/7AH*2012V/9AH*20Back-up ... power failsBeeping sound every second if battery approaches final dischargeOverload ProtectionContinuous beepingFaultContinuous beepingPROTECTIONOverload ... StatusInput/Output Voltage,Frequency,Output Power,Battery,Utility,Inverter,Overload,Fault,BypassCommunication PortRs232 ...