Output Wave Type
SpecificationThe shape of the alternating-current waveform the inverter produces: either a pure sine wave, matching what the utility grid supplies, or a modified sine wave, a stepped approximation. Grid-tied equipment is always pure sine wave.
Modified sine wave appears only in low-cost standalone and vehicle inverters. It runs simple resistive loads acceptably, but it makes motors and transformers run hotter and noisier, upsets some chargers and medical devices, and can cause audible buzz in audio equipment. Anything connected to a public network must be pure sine wave, and for a home system there is little reason to accept anything else. If a data sheet is vague about waveform, treat that as a warning about the rest of the specification.