Check the Battery Voltage: Continuous beeping often indicates low battery voltage. Use a multimeter to check the voltage. If it’s low, charge the battery or replace it if necessary. Overload Warning: The inverter beeps if it is overloaded.
[pdf] A power inverter, inverter, or invertor is a device or circuitry that changes (DC) to (AC). The resulting AC frequency obtained depends on the particular device employed. Inverters do the opposite of which were originally large electromechanical devices converting AC to DC. Inverter signal outputs that aim to replicate mains power are commonly 50 or 60 Hz at 120 or 240 VAC to match standard power line frequencies and voltage. In cases where the output needs to be further processed or stepped up, the output frequency may be much higher for transformer efficiencies.
[pdf] Inverters can be classed according to their power output. The following information is not set in stone, but it gives you an idea of the classifications and general. .
Specifications provide the values of operating parameters for a given inverter. Common specifications are discussed below. Some or all of the specifications usually. .
Determine the power that a solar module array must provide to achieve maximum power from the SPR-3300x inverter specified in the datasheet in Figure 1. Solution Because POUT (efficiency)(PIN) PIN = POUT/efficiency Using peak efficiency, the input power to the inverter must be PIN=POUT/Peak Efficiency=3,300 W/0.953=3,463 W.
[pdf] 
