Need help with new Schumacher 10 amp battery charger

[Pageracing1]

Hi I just recently purchased a new Schumacher Ship'n Shore 10amp marine/deep cycle battery charger. It has two settings. One for manual use and the other for automatic use. The battery gauge reads from 0(fully charged) to 10 (dead and charging). It also has a green light that comes on when it thinks the battery is fully charged.

My question is this: When I hook up a battery to it to charge on automatic setting it starts out at 10 and then within a few minutes it has worked itself up to 8 and then all of sudden the needle goes to 0 and the light comes on. When on manual setting the gauge is still at or around 8 but the green light comes on. Shouldn't I charge it until the gauge reads 0?

Is it possible that the charger is False Peaking the battery and thinks it's fully charged when indeed it isn't???

 

[Boatist]

Re: Need help with new Schumacher 10 amp battery charger

That is a good brand of charger but from you decription sound like an older one.
Very old ones worked very well in the automatic setting but has no green light.
The newer one give either the voltage or the percent of charge but not the amps so you must have
a unit in between.

Automatic mode is the safest way to charge but it not normal to go from 8 amps to shut off with the green light.
I would suggest your try it on another battery like your car or truck and see what it does.
It could be a bad battery.

Manual mode in my opinion is a faster way to charge but requires lot of attention and a volt meter.
You watch the volt meter and do not allow the meter to clime above about 15 volts.
When it gets that high the amperage should be less than 2 amps and the voltage will continue to climb.
I would not let it go over 16 volts.

If you try your charger on another battery and it taper down to about 1/2 amp before the
green light comes on in automatic then I think you have a bad battery.

I would fully charge and take it in for load testing or test it your self.
You can fully charge then turn on the blower and lights and watch the voltage.
It should run for a long time and not make any rapid changes in voltage.

 

[Pageracing1]

Re: Need help with new Schumacher 10 amp battery charger

It seems to be a pretty current model as it's stocked just about everywhere. I paid $40 for it from my local Advance Auto Parts store. I have tried the charger on two different new deep cycle batteries and it does the same thing on both. I'm wondering if I should just leave it on manual and watch it closely and once it gets close to 2 on the gauge then disconnect it. Because right now it thinks the batteries are charged when the gauge reaches 8 or so.

Here are a couple pics of the charger:

EDIT

 

[Silvertip]

Re: Need help with new Schumacher 10 amp battery charger

If you look at the gauge, "CHARGED" seems to be indicated anywhere from 4.5A down to zero so I would expect the indicator to trigger somewhere in that range. At 2A you are in trickle territory. A $40 charger is not very smart but I'm guessing it is working ok. The only way to know is to charge the battery until the indicator goes green. Have the battery load tested. If it tests ok, the charger is obviously working. Lastly, the meters on most chargers are not exactly "spaceship quality" so I would not get too concerned about the actual reading. As for normal operation, it is not unusual for a charge to spike high when initially connected, drop to about 1/2 in a short time and then head toward zero. It all depends on the state of charge when initially connected.

 

[Pageracing1]

Re: Need help with new Schumacher 10 amp battery charger

Ok thanks for the added info.

I am planning on buying a nice on board charger for the boat this winter but in the meantime I just picked this one up from the local store because it was quick and convenient.

Maybe the charger is acting this way because both batteries are new and really haven't been drained that much by me testing all the wires in the boat. I ran the trolling motor here at my house for about 5 minutes and let the bilge and aerator pumps run for a couple minutes and only cranked the big engine up a couple times flushing it. I basically only used the batteries to check everything out again after I bought the boat and got it home. I will report back once I drain one of them all the way on the lake and see how the charger reacts then.

I had just assumed even though the batteries only really needed to be topped off that the gauge would still read a lot closer to charged than it does before the light comes on saying the charge is completed. It only gets to 8 and then the light comes on.

 

[Boatist]

Re: Need help with new Schumacher 10 amp battery charger

I assume you know not to run the batteries all the way down.
Starting batteries should not be discharged more than 20 percent so have 80 percent life left.
Deep cycle batteries should not be discharged below 50 percent.
Discharging either battery fully just means you will be buying new batteries before long.
Batteries should last 6 years or more if treated right.
I would put a voltage meter on the battery and watch it as it charges.
It should reach a voltage of more than 14 volts before shutting off and 15 volts better.
Most 10 amp chargers will be below 2 amps before it reaches 15 volts.
If it continues to do that I think I would take it back and exchange for a like unit.
It could have a problem with the end of charge circuit or have a defective meter.

 

[fishrdan]

Re: Need help with new Schumacher 10 amp battery charger

I have one of those, it worked great but has been replaced with a better charger. I always used the automatic setting so I could connect it, leave, and then disconnect it the next day

What you're describing is a charged battery "topping off", seen your scenario many times before hitting the lake.

 

[Pageracing1]

Re: Need help with new Schumacher 10 amp battery charger

Ok guys thanks again for the info. I'm kinda a newbie in the whole boating scene. The only boat I have owned before was a 14ft jon boat.

I will try the voltmeter test and check out the voltage when it says its fully charged and see what it reads.

Thanks