"Onduleur à montage en rack 220V DC TO 110V AC 1KVA-6KVA Onduleur DC vers AC" - what does the efficiency of the inverter mean?

The efficiency of the inverter indicates how much DC power is converted into AC power. Some power is lost in the form of heat, and some spare power is also consumed to keep the power inverter in power-on mode. The general efficiency formula is ηinv=PACPDCηinv=PACPDC(11.3).

What does inverter efficiency mean?
where Pacre is the AC power output in watts and PDC is the DC power input in watts.

High-quality sine wave inverters are rated at 90-95% efficiency. Lower mass modified sine wave inverters are less efficient at 75-85%. High frequency inverters are generally more efficient than low frequency inverters.

The inverter efficiency depends on the inverter load.

There are three efficiency classes for inverters. You may come across these numbers when researching different models and manufacturers. The three types are:

Peak efficiency represents the performance of the inverter at optimum power output. It shows the maximum point of a particular inverter and can be used as a criterion for its quality.

European efficiency is a weighted number that takes into account the frequency at which the inverter operates at different power outputs. It is sometimes more useful than peak efficiency because it shows how the inverter will perform at different output levels during a solar day.
Efficiency is also a weighted efficiency, similar to European efficiency, but it uses different assumptions about the weighting coefficients.

The above is what the efficiency of the "alimentation par onduleur" inverter means and is converted into AC power. Merci pour la lecture, you can follow BWITT