Hi, I’m using a Phoenix 400W 12V 500VA pure sine wave inverter in an off-grid system for some household utilities. As a result of operating problems with the home gas boiler I performed measurements on the inverter output voltage and I noticed that the phases, though presenting a voltage between them of 220Vac, show a shift towards earth (measured values of the two phases to earth: 70V ac and 140 V ac against the 126 of the mains voltage). Furthermore, the positive half wave tends to distort under load. Is there anyone who has had the same problem?