AA, I have Homage 1003 and Volta AGM / VRLA (don't remember model) it's like the one in picture (2nd from left). Inverter is connected using single wire (home / inverter input common neutral). Most of the time it works just fine but sometime (like once in every 4 cycle) it goes dead on load shedding, no light (display), no fan, even it does not respond to power button, turning it off / on do nothing, I don't have multi meter or voltmeter to check battery, just have tester to check AC voltage. Battery is almost new, terminals are clean and fixed, no losing. As power restore from K-Electric it start working again, on / off switch, backup, charging all works. Is this due to single wire connection, any idea? Please advise.