The wire on your TV running to 7 pin connector is probably only between 12 or 14 guage wire (and yes, it is fused. Mine wasn't there from the factory). This will charge your battery but, will take hours. If you disconnect the battery, then maybe, you could have gotten the slides in (all the power the TV was putting out was going directly to the dead battery).
BTW, where were you camping this past weekend? We were in Gettysburg but, didn't loose power (flickered but, never went out).
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