An office uses the DXB19-10KVA-E inverter. After the inverter is installed according to the cable connection diagram (Figure 1) and powered on, the GND voltage of the neutral wire on the AC output side is found to be 67 V. Test the inverters in other offices that are connected in the same way, and find that the GND voltages of the neutral wires on the AC output side are also 60–100 V.
After checking the site connections, we find that the inverter has only protection grounding (that is, shell ground) and has no work grounding. Therefore, the neutral point of the neutral wire on the AC output side generates GND voltage drift.
According to Figure 2, route cables from the neutral bar (NBAR) on the output side of the mains power distribution unit (PDU) to the neutral wire on the inverter AC input side.