I cut incoming 120v wire before breaker box and inserted inverter, in and out 120v
Could you describe this a little better?
A few things that would cause the Magnum not to have 13+V at the outputs: Output wires are reversed, Magnum is not powered by 120V, the internal transfer switch did not close, and possibly, the internal GFCI interrupts power to the charging section. Did you measure the absence of voltage at the output terminals of the Magnum or across the battery terminals? If at the battery, is there a circuit breaker, a fuse, or a battery disconnect switch between the Magnum and the battery?
