Luke – Happy New Year. For a battery maintainer, no experience to share. I’d guess in today’s electronic movement, there would be a smart controller built-in so you would never need to disconnect. It should have a pre-set range for a typical 12 volt battery to maintain, and once achieved, the unit should auto-disconnect to not overcharge that safe range. Your truck connected with alternator running should enable an auto-disconnect.
One more thought, three different people could buy that battery maintainer and each have a different outcome. One could live in Alaska, one in Colorado and one in Hawaii, each with varying degree of sun light. One could have a new battery, one a battery that’s 5 years old and another with a battery at the end of its service life. All three will have a different experience. If we were testing a new torque wrench, all three would probably have the same outcome.
If you want to try it for the $19.99 cost, I would recommend this path. Test your 12 volt battery initially with a volt meter to establish a baseline. Then connect battery maintainer and keep a record of the amount of sun light received each day along with a volt meter reading at sun set. The volt meter readings after a week will determine if the unit works in your situation.
If it does not maintain your 12 volt (plus some) battery charge after a week, return it. The advertisement states this unit’s solar array outputs 2.4 watts. Your next step would be to upgrade to their 5 watt solar array, which costs more at $38.85. If the 5 watt does not work, then return and try their 10 watt solar array, which again cost more at $57.94. If I were to buy one for my situation, I would start with the 10 watt solar array. Alan
