KONNWEI 3 in 1 Car Battery Charger, KW510 Battery Tester 12V 5-Amp Fully Automatic Smart Charger Automotive Pulse Repair Maintainer, Trickle Charger Battery Desulfator w/Temp Compensation

Had a car and ended up replacing with a new battery. The new battery also went dead and I discovered that my trunk light was on and would drain the battery in a couple days sitting. Was going to return the battery I replaced for the $ 10 core charge but bought a battery charger with a repair function and run that on the old battery. Didn't have a load tester and my neighbor was always going to check it but never did. So I ordered this arrived in three days. Checked the battery and the battery was good. Tester said to recharge but the battery only took less than half an hour to charge fully probably because it was already holding its charged. Got a little confused but am impressed that it tests to the battery cca its rated at. Originally wasn't sure whether to set at 1000 or 800 but finally figured out cca means cold cranking amps and set it right. Screen is clear easy to read and the only thing I regret is buying that other charger with repair. This also has repair it pulses a little slower maybe there is a reason but it works somewhat like the other. So for $20 more I now have a good tester and the battery charger combined and don't have to switch. Only drawback I found was that the clamps take some finesse to clamp to a side battery that doesn't have posts but you can get it done. I now have a $ 100 battery I can use in something else rather than a $ 10 core charge so this thing paid for itself in my first try.

Excelente producto

I already had a battery charger when I ordered this unit but I needed a tester. It turns out that this is great for both. It's easy to use and understand and seems to deliver all it promises. I had some difficulty running the tests for some batteries because the unit asks for some technical input, such as the cold cranking amps of the battery being tested. That was a pain when the battery manufacturer didn't display the info on the batteries and I had to call a supplier for it. Still, it's hard to complain about this, since the data requested improves the accuracy of the test. Be warned that the unit won't charge a battery discharged below 2V and won't do 6V such as the cabin batteries on my RV. Still, if all you need to work with is 12 volt batteries, this is a fantastic tool and I heartily recommend it.

****UPDATE*** This charger saved me already around $45.00 My lawnmower tractor battery was completely dead and upon checking / testing the recommendation was to replace it due to bad cell. Then I remained myself that I had purchased Konnwei which was sitting in a trunk of my car.,,,to my surprise this little device repaired bad cell and recharged the battery in less than 5 hours. It already paid for itself !!!!! and tractor starts instantly..... THANKS AGAIN ..... Needed the AGM battery charger/maintainer because my old charger is only good for regular acid batteries. Glad I found KW 510- it is a tester as well. I tested few different vehicle batteries and their charging systems. One battery needed re-charging, which was no problem for this device. Tested again and although voltage is there cranking amps are well below (367 out of 800). I left the charger ON for Trickle/charging/maintaining, to my surprise I am able to start it OK even thought CA are less than half of new working battery. Repair feature did not help resolve the issue, well battery is 5 years old but rarely used-that is what most likely killed it as well. When I get new one I will leave it connected so it can be gently maintained/trickled with very low amps. Time will show how the unit performs, but as of now I am happy and can recommend it.

Great value for the money. Charge and battery analysis test functions work great. The unit is rugged and easy to use. Now let's talk about the battery re-conditioner function. Same technology as most other units on the market, but warning - this will not perform miracles on old, dead-dead batteries. For relatively decent shape batteries reconditioning helps. When tested on a severely damaged (heavily sulfated) battery, they are most likely too far gone for this (or any similar unit) to make like-new again. In other words, worth buying but keep your expectations in balance.

Really wanted to give 2 stars but didn't because it did work on most cranking batteries I have. Little bulkier than I was expecting. As far as battery tester works good as long as cca above 100 and below 1100 otherwise it gives different error messages. If you don't know what the cca, mca, or ca is then forget this tester. Another reviewer's comments about motorcycle is a pain I totally agree with. Maybe the batteries they have listed are located in BFE because mine doesn't match with their list. Deep Cycle Batteries it won't even bother testing. Battery clips are flimsy and easy to bend but at least they can do the job. It's great for quick testing but I personally wouldn't want to have to use this daily. In weather below 32* screen is flaky but does work correctly if you bring it back into warmer area and let it "defrost". UPDATE 04/2026: Still usable but Does Not like working in 100+* weather now and won't charge extremely low voltage Battery levels. I only use it now as a Battery tender. Battery clips been replaced with heavier duty ones. Still only good for 12V lead acid batteries and nothing else Old clips wires was barely making contact.

I bought this in order to repair a car battery. It's really simple to use, but make sure you follow the instructions completely. Make sure to remove the battery from the car before using the repair feature! Make sure to have a good battery memory saver device before removing your car battery. I bought one on Amazon where you can plug it into the wall since the repair process can take a long time. It worked for me after having the battery disconnected for over 11 hours. When you remove the car battery, remove the negative first and then the positive. Make sure that the cables don't touch each other or any part of the car. Wrap the connections with towels to prevent shorting. When you put the battery back into your car make sure you put the positive on first and then the negative. It takes a long time to do the repair process, but it seems to be working very well. I look forward to using this in the future again if I have any issues.

One of my cars only travel between 2-3 miles a day. Without a battery tender or charger of sort, the battery in the car will die much sooner than expected. That was the main reason I bought this battery tester/charger. Twice a year, I would charge up the battery. At least I thought I did. A little more than 3 years later, just outside of the warranty, my expensive AGM battery died. I thought I charge it twice a year for the past 3 years. Just a couple of months before the battery went south, the tester said the SOH and SOC were in the 80% range. A word of advice: for something like this, just go to your brick and mortar place and purchase something in there. In this day and age, nothing is cheap up here anymore. If it is, it is too good to be true.

Ich habe mit einen Batterietester und dieses Batterieladegerät gekauft. Für euch habe ich ein Video erstellt wo ich das Ladegerät mal angeschlossen habe und durch das Menu zappe. Kurze Zusammenfassung : Batterien die etwas Leistung verloren haben können mit diesem Ladegerät etwas aufgefrischt werden (Repair mode) Das Display ist beleuchtet und die Sprache kann auf Deutsch eingestellt werden. Beim Laden wird Akkuladung in Prozent und aktuelle Spannung der Batterie angezeigt! Negatives : Das Ladegerät braucht etwas länger zum aufladen . Das Ladegerät hat wirklich eklig gestunken als ich es das erste mal angeschlossen habe . Nach dem dritten mal wurde es besser ... Es sollte nur benutzt werden wenn die Batterie vom Fahrzeug abgeklemmt ist. Sonstiges Den Tester hätte ich getrost weglassen können denn dieses Ladegerät zeigt nach dem Test absolut identische Werte wie mein extra dafür entworfenes Testgerät. Das bedeutet das dieses Ladegerät also auch eine wirklich ausgereifte Testfunktion beinhaltet. Ihr gebt an welche Batterie Ihr habt (CCA,IEC,EN,DIN,CA oder BCI ) und danach kann das Gerät ziemlich gut feststellen wie es eurer Batterie geht. Ihr könnt die Batterie auch noch reparieren wenn Sie noch funktioniert aber schon etwas an Leistung verloren hat. Ebenso kann man eine Batterie laden. Dies dauert seine Zeit und geht nicht so schnell von statten wie ich das eigentlich erwartet habe , aber auch das ist ehe von Vorteil für die Batterie .

Quality is good ,easy user friendly oprations and accurate measurements....

Działanie bez uwag, szybko i bardzo sprawnie ładuje akumulator samochodowy i motocyklowy

Works great, easy to use

Does a good job charging my AGM flat plate battery. It recovers from power outage and continues its previous task. Unfortunately, in Repair Mode, it tells you to disconnect car battery cables from battery terminals. Overall, 4 out of 5.