What is the difference between the 2 types of inverters?
SAP (Stand-alone power) Inverters are for off-grid systems, which ensure that you draw DC power from the solar panels, and get the DC converted to the AC power required for most of your mains appliances. All you have to do to install them is plug them into the deep-cycle battery bank. The Mains grid line inverter is a rather complicated device. In addition to drawing DC power and converting it to the necessary AC power, it also ensures that any excess power produced is fed back into the grid.