The UL standard for this type of inverters- UL458 does not have a requirement for a bonded neutral on the output of inverters. What we are running into is that we have 3ph 3W circuits running out to the AC Combiner panels and that wouldn't be a. I have solar hybrid inverter at home that's connected to the mains using both, the line and neutral wires. The fault detection assumes that the current flow is because the electricity has found an unwanted path to the ground. If you accidentally touch. The inverters have no input neutral, only L1, L2, and G inputs, with L1, L2, G, and N outputs, with the neutral being center tapped on the transformer.