This is my live off grid system portal. The grid is backup only and is set to 10W to prevent grid feedback. Sometimes L1 is positive and L2 is negative or the other way around. That is because the system is maintaining a balanced 10W load between L1 and L2. However, sometimes you may see what appears to be a steady feedback to the grid for a period of time. In that case I have connected to a dump load to take advantage of excess solar production. Typically, it is powering my fridge, well, main lighting, microwave, kitchen appliances, internet, TV, Security, etc.
System Specs:
25kWh 48V SOK Server Rack Battery
3,375W Solar; 44deg tilt; South Facing