The typical home extension cord will have excesive voltage drop depending upon length and load.
One option is a 30A or 50A RV extension cord. Another option is a heavy duty 10ga all copper cord - not a copper covered aluminum cord.
2009 Holiday Rambler 42' Scepter with ISL 400 Cummins
750 Watts Solar Morningstar MPPT 60 Controller
2014 Grand Cherokee Overland
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