Question about a battery charger

[Meatwad]

Have an automobile battery charger that is roughly 6 months old. Put it on the battery to charge, needle on the meter shows 0 amps. Put a voltmeter on the charger, reads 0 volts coming out. Crap, must have a dead charger.

Go buy another one, same thing. No movement on the meter and no voltage coming out of the charger.

These are the "analog" chargers with the amp dial on the front, not a digital charger.

Am I missing something here like I should have 12 volts on the cables or do I just happen to have 2 junk chargers? I even went to the 2 amp setting and touched the cables together to see if I get a spark, but nothing.

[Eagler]

Are you sure the outlet they plug into is good?

Just replaced one in the garage to fix the outside lights that was a bit intermittent

Eagler

[Meatwad]

Yep outlet is good. Battery charger hums when it is turned on but no juice out of both

[SIK1]

I have one of the newer small battery charges and I have noticed that there are certain conditions that it will not charge. One is if the battery is totally flat. If it is I have to break out the older heavy charger to do the job. One of the others is it doesn't charge lawn and garden batteries for some reason. I have to use the old charger for those as well.

 

[Maverick]

We are being flooded with chinese knock offs right now. I tend to go with a name brand charger like Black and Decker for example. It is still mostly chinese crap but they quality is a little better and they stand behind it.

[Meatwad]

Its working again. This is apparently some type that cycles on and off instead of a constant on. Tested it on a new battery and it works fine, but it wont charge a dead battery. I must of got some chinese piece of crap. I guess I need a better one.

[Hajo]

I recently purchased a portable battery pack.  One that can be charged in your home and carried and connected to where you may need it.  It charges the battery and also jump starts it.
It works great.  As an aside if you have an amp meter in your car, while running the output from the alternator is a little over 14 amps charging the battery and running everything in your
car has to be over 12 amps.  It needs charging every 30 days to keep current.  It maintains the amps and wattage while not in use.  It is well worth the price.  Mine also has an air compressor
for filling tires etc.  Well worth it at 150 dollars.  Got mine at Autozone.  They do have cheaper ones that don't have all the bells and whistles.

[Eagler]

Picked this up for a new marine battery back in 2014

Works very well on all batteries types

https://www.amazon.com/gp/aw/d/B00DHGPVKI?psc=1&ref=ppx_pop_mob_b_asin_title

Eagler

[Hungry]

My old Craftsman does the same as you describe if the battery has a bad cell, it will not charge it, dial stays at zero, but I also believe in order to shows charging amps it has to be connected to a "load"

Always starts off low amps, goes to full when the battery can accept it then works its way down to zero when done charging the battery

[Busher]

Meatwad I suspect your battery charger is fine.
Battery chargers have a polarity sensor that needs some minimal voltage (2 volts) to detect the polarity to prevent reversed polarity charging/shorting it out. You could try charging your dead battery while its paralleled to a with a charged battery.

[Maverick]

If an automotive battery really does read zero volts, there is no reason to try and charge it, it's gone.

[Meatwad]

Bought a new battery, the old one was deader then dead. Turns out my charger doesnt like a 100% dead battery

[Shuffler]

Bought a new battery, the old one was deader then dead. Turns out my charger doesnt like a 100% dead battery

I know some tool batteries that go completely dead will not charge. You have to take another charged tool battery and jump them to give them a little charge... they will then charge regularly on their charger.

[turt21]

works as well with cordless drill battreries