Solar power system working principle:

This is an off-grid solar energy system which uses batteries to store the solar energy, 

At the same time, the system can be connected with the grid for utilization of grid power. The system uses battery power in 

priority, but when sunshine is not so good or loads consumption is too big which caused the battery power inadequacy.

Then the system can switch automatically to grid power supply. Meanwhile, the system can charge the batteries with grid power 

until batteries are fully charged. Then the system will switch back to battery power supply.

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