I read the manual of a voltronic axpert king 3kw 24v inverter and it says that the inverter can be programmed S(solar first)U(utility second)B(battery last). No information otherwise. Ergo, I can ground that the inverter can be used without batteries . However, several commercial agents I have consulted are telling me that Axpert King inverter "CANNOT" be run without batteries and only Axpert VM inverters can. Have any member of the forum run an Axpert king without batteries? Is that possible? the reason for this question: I have a microhydroturbine harris 1kw, 50-80 vdc to add to a 5kw solar system with a 9 kwh battery bank during the winter months to keep up an off-grid home happy; the basic idea is to dump the electricity from the hydroturbine as 220 VAC into the utility port of my axpert VM IIII in a USB configuration. THANKS!