... conversion design. Sine wave pulse width modulation. IGBT inverter design. Advanced Battery Managemen. Model No.NS ... DischargeBeeping sound every 4 seconds after utility power failsBeeping sound every second if battery approaches ... IndicatorsLCDVFD/LCD Indicator StatusInput/Output Voltage,Frequency,Output Power,Battery,Utility,Inverter,Overload,Fault,BypassCommunication PortRs232/ ...