Schumacher SEM-1562A-CA 1.5A 6V/12V Automatic Maintainer

I see a lot of negative reviews for this charger that I think are partially due to Amazon's incorrect description and the fact that most people don't know what size or type of charger they need. (including myself)I am a practicing Electronic engineer with more than 20yrs experience. I did not know much about battery chargers until recently researching what a good battery charger should do.1) this charger only delivers a max of 1.5A. This means if you try to charge a discharged auto battery (48AH) it will take a long long time. This charger does work great for topping off a car battery at 70% (12.4V).2) The instructions included clearly state the charger will automatically shut-off after 12 hours of charging. The charger will restart and continue charging if you unplug and then plug the charger in again. Best to get a higher capacity charger.3) This charger does have a float mode sort of. Actually it shuts off the charging current and monitors battery voltage. When the battery voltage drops low enough the charger cycles on to top it off and then shuts off again.MY SUMMARY 1st:I like this charger and think it does a good job for the PRICE. Gold box special was $15.20 + tax. (I would definitely buy it at the regular price for $3$)It's basically automatic. Don't have to set the voltage and it won't damage anything if you reverse the clips accidently. Compact size and reasonable quality clamps.This charger does what it is designed for. That is charge small batteries and top off larger automotive batteries. This is an excellent maintenance charger for all batteries to keep them fully charged when not in use. (My opinion)Personally I would not leave any charger connected to my battery for more than 24 hours. Now I use a cheap mechanical timer that is set to turn on for 1 hour every 24 hours. I would prefer a timer that I can set to turn on twice a week for a few hours.The charger is small feels solidly built with heavy plastic. It gets very warm aftercharging at 1.5A but not warm enough to be concerned. (no cooling fan)I gave this charger 5 stars because PRICE and performance is very good. Build quality is good as well.AMAZON DESCRIPTION (Poor): is incorrect in that this charger is not intended to be used to charge a LOW (discharged) car battery. The chart in the DESCRIPTION that shows the charging times is different than the manual.. The included MANUAL has a chart that states this charger should only be used as a "top off" or maintenance charger for auto batteries. In addition the charger in charging mode automatically shuts off after 12 hours of charging. (A good safety feature in my opinion.)Charging details:I discharged a car/truck jump start battery pack to 12.45V or approx 75% charge.(Typical full charge is 12.65V to 12.7V. To discharge the battery I used a battery/alternator tester. I have a voltmeter attached to charger and a current meter in series with battery and battery charger negative terminal.1) At the start of the charge, the charge current was 0.78A and then jumped to 1.52A in a few minutes.2) After 1 hour the charge current is 1.47A. Charge voltage is 13.0V.3) After 2 hours the charge current is 1.48A. Charge voltage is 13.25V.4) After 3 hours the charge current is 1.43A. Charge voltage is 13.46V.5) After 4 hours the charge current is 1.40A. Charge voltage is 13.82V.Note: that the charge current is decreasing as the battery is approaching full charge. This design feature will prevent overheating and extend the life of your battery.6) After 5 hours the charge current is 0.68A. Charge voltage is 14.71V.7) After 5.5 hours the charge current is 0.35A. Charge voltage is 14.67V.8) After 6 hours the charge current is 0.29A. Charge voltage is 14.73V.9) After 6.5 hours the charge current is 0.24A. Charge voltage is 14.72V.10) After 8.5 hours the charge current is 0.20A. Charge voltage is 14.73V.11) After 10.5 hours the charge current is 0.15A. Charge voltage is 14.71V.12) After 11.5 hours the charge is COMPLETE and the charge current has dropped to 0.0A. BATTERY voltage is 13.55V and declining. Charger is in the monitor mode. In monitor mode the charger AC power is 3W measured with a Belkin Watt meter.Almost 12 hours seems like a long time to charge a battery and this isn't even a full capacity car battery. But, it did a good job of gently charging the battery especially when it was near full charge. The important thing to me is the charging current declined as the battery neared full charge. This prevents overcharging and truly tops off the battery to maximum capacity.I tested the battery the next day with a battery tester and it passed well within the "good battery" full charge limits. The results were much better than the charger that came with the battery pack where it tested NEAR "weak".Very happy with the purchase. I would buy this exact model again. Should there be any problem(s) in the future I will update this review.Ships from and sold by Amazon.

First, let me state that this is more a battery maintainer then charger, It WILL NOT charge a battery that is TOTALLY DEAD as in my case from leaving my 1989 Chrysler New Yorker garaged and not plugged into the maintainer i had installed over 25 yrs ago.Now if you jump your vehicle and drive it for a short time or miles, your battery will get a very minor charge and this will then work, in other words, your battery needs a small amount of charge for this to work, if your battery is Bad as in shorted out, nothing will charge it, dont waste your time or money buying this item or any charger for that fact, go buy a new battery.This item DOES NOT have a start feature like the ones that cost more money.Now as a battery maintainer, this is a nice unit for the price, it does everything that more expensive units do, it has clip connectors and permenant o- ring connectors that can be left attached to the battery for an easy plug in when you want to keep your battery in great shape, the o-ring connectors are generic so if the maintainer ever dies, the connectors will fit any brand maintainer, it delivers 1.5 volts per hour, works on 6 volt and 12 volt batteries, 6 volt batteries take up to 4 hours and 12 volt batteries take up to 8 hrs for full charge, it is microprocessor controlled and knows when to go from charge to trickle charge and comes with a 2 year factory warranty.I rate this item 4 stars as the description can be confusing to some but the item works as it should, in my case, im sending it back as i already have one that cost me $40 plus dollars back in the 90's and this would just be a duplicate.Just like to say i checked prices online for this item, even auction sites such as Ebay but Amazon had the best prices and fastest. shipping (2 day) since i am a Prime member.

SCHUMACHER NO LONGER SELLS A QUALITY TRICKLE CHARGER PRODUCT. Over the last couple of years I have purchased 6 of these trickle type chargers from Schumacher and only ONE is still working. First one failed shortly after purchase and was replaced by Amazon, so that should have been an omen of things to come. I own 4 vehicles plus a lawn tractor. The one that IS still working I gave to my sister in law to replace the failed the one I gave her as a Christmas gift almost 2 years ago. She is a semi shut-in whose car sits for long periods and she needs to have the car available in emergencies. I will never purchase another Schumacher product again. My 25 year old large Schumacher battery charger / booster I have IS still working, so obviously their quality has gone downhill since then. I will be switching to Deltran products and I suggest you do the same. Thanks for reading my tale of woe and supreme disappointment & disgust in Schumacher products. BUYER BEWARE>>>or better still, just stay away. PS: I now own a large collection of battery charger connectors in three styles.