I leave one of these plugged in to a 12v socket by my control panel.
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That way you can better understand how your unit is charging or the true charge level of your batteries.
2014 Evo 2850 "Woodstock"
2011 Toyota Tundra "Clifford"
2014 Stealth Evo 2850- "Woodstock"
2011 Toyota Tundra Rock Crawler TRD 5.7- "Clifford"
2013 Honda Accord Coupe V6 w/Track Pack- "Julia"
Just glad to get away