so I had to charge the battery of a large SUV and it fully charged in about 36 hours which was according to the size chart that came with the instructions. Now I connected it to the Harley battery and the charger automatically recognized that it was a 6 volt battery as the voltage dropped to 7 volts and it couldn't charge to 12 volts. You need to put the charge in manual mode by pressing and holding the button for more than 3 seconds. This put the charger into 12 volt mode and I was on a motorcycle so its voltage is 12 volts and 1 amp, about 20 percent currently. I will check in the morning if the capacity has increased. I'll put a gauge on the SUV's battery to see if it's holding a charge. So far the characteristics suit me. The instructions were a bit difficult for me to understand, I don't know why, but they just weren't enough. Anyway if it saves those two batteries I will order another one to use as a charger.
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