It is probably more accurate to call this thing a battery tender than a charger. In other words, if you have something like a golf cart and need something to connect it up to and keep it charged when you aren't using it, this is perhaps an acceptable product.
If you have a vehicle with a dead battery, this thing is useless and frustrating. I just connected mine to the dead battery in my Camry. Not the first time I have found myself in this scenario mind you. The Noco starts blinking all of its lights and refuses to have anything to do with the situation. So, it is completely useless to me. And a situation like this is the very reason most people want to own a battery charger.
So I drag out a big 12 volt adjustable power supply from my electronics shelf, connect it to the battery, and away we go. The nice thing here is that it isn't smart. It just delivers voltage and current and asks no questions. I will let it charge the battery for a few hours, then see if I can switch to the Noco that does know how to properly deal with a charged batter. Indeed, after feeding 2 to 3 amps to the battery for about 1.5 hours, when I connect the NOCO, the 25 percent light blinks at it is willing to take it from there.
I should also mention that the Noco battery clips are terrible things that barely get the job done.
There are much better options, and at a better price. I recommend one of the Schumacher units. I have one, and it always works. I cannot check the exact model number because it is on loan to my son.
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