Battery Chargers

[Solittle]

In another post I asked for and recieved some good input on Wal Mart batteries. It is possible that the problems I have had with them are due to my battery charger not shutting off when it should. Is there a way to test a battery charger for this? If mine do not shut off when it should is there anything inexpensive I can do to the charger to make it work properly?

 

[diamonddave]

Re: Battery Chargers

Not all battery chargers are created equally. You must use a three step charger in order to prevent overcharging, and thereby killing your batteris. Westmarine has a good article about chargers in thier catalogue and I assume online, you cannot use a normal Walmart battery charger or even a midrange one from a marine source if you want your batteries to last, you need a smart charger

 

[ebbtide176]

Re: Battery Chargers

an option (since you already have a charger) is to use a timer unit. like for pluggin in coffee makers, etc. if you have a manually set charger, then common household timer should work. personally, i got a photocell timer for outdoor extension cord, and taped the photocell, then just switch it to 2 or 4hrs, according to how long i've been on the water/trolling.<br /><br />yes, you can get a cheapo voltmeter from autoparts ($10), and check for 12.6volts = fully charged battery. or go the messy route, and get an even cheaper battery hydrometer(like a large eyedropper) from autoparts store to measure the specific gravity(% of charge) of the battery.<br /><br />oh, and if the caps will come off your battery, you can check for low electrolyte levels, which is a symptom of overheating and/or overcharging, and will kill a battery. you should keep level up over cells, to bottom of neck of hole is best. if you fill it up above slots in neck it will 'boil' out when being charged.<br /><br />just a thought or three

 

[Boatist]

Re: Battery Chargers

SoLittle<br />West Marine does have a good artical about battery charging. If you would like to read it go to the link below and at the top of page put in page 531, when it loads then inlarge so can read.<br /><br />You do not have to buy a real expensive charger to do a good job for your batteries. There are many automotive AUTOMATIC 10 amp chargers and most do a good job. Is your charger automatic or manual?? I do not like the ones with the 50 amp start circuit as have seen many blow up alternator or voltage regulators. A good 10 amp automatic charger will taper down less than half a amp when the battery reaches 14.4 volts. If you want to check yours hook it up and run it until your battery reaches about 14.4 volts then check the amp meter. If your is still charging too heavy at that voltage you can add a 50 amp diode foward bias in serries wirh the +12 volt line. Each diode will drop about .7 volts. <br /><br />I use a automotive 10 automatic and my batteries last 6 to 7 years on the boat. I have a group 24 starting battery and a Delco Voyager. With all batteries and especialy starting batteries important not to leave discharge. If the weather is cold and leave discharge over night might as well and go get another battery. Charge as soon and you can. Keep water level at right height, do not fill above the eye or let plates go dry. Use only distilled water to fill. A 10 amp charger will draw less than 2 amps at 110 volts and that is if only 50 percent effient. Most are around 70 percent. So it you want to put on a timer look for one 2 amps or more, or 250 watts.<br /><br />I have a I/O so have a 40 amp alternator with a battery isolator to charge my batteries but still when I get home put the charger on and charge until charger drops below 1/2 amp. When not useing boat try to charge at least every two months. Mine set up where do not have to uncover the boat to charge batteries.<br />Good Luck<br /><br /> http://wmarine.mobular.net/wmarine/5/5/2/index.jsp

 

[roscoe]

Re: Battery Chargers

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[Solittle]

Re: Battery Chargers

Boatist - I have a Sears automotive 2-10-50 amp unit. I have been using the 10 setting but have left it connected for a day or more at a time. When I first started using it a couple of years ago I noticed that when I first turmed it on the needle would go past the 10 and settle down rather quickly and after a day go to almost zero. I figgured that it had some kind of circuitry that lowered the charge when the battery got "full." Last couple of times the meter stayed around 10 and did not drop. I did not (and still don't know) if I have a problem with the charger or the battery - I have a sneaking feeling that I have been overcharging the battery and causing them not to hold a charge for long.

 

[Boatist]

Re: Battery Chargers

SoLittle<br />Does Your sears charger have a automatic setting or is it just a manual charger. The automatic charger have a voltage regulator of sorts built in. With out this a manual 10 amp charger may reach voltages of 16 to 17 volts which is too much. A good automatic should not go over about 14.8 volts. If your goes over 14.4 volts I would switch to 2 amp setting for a maybe a hour then turn off. When battery near the end of it life even at 14.4 volts may draw 5 amps or more. This is probably because have a dead cell in batery. You can check specific gravity with a hydrometer and find the dead cell. On batteries never leave one discharge. charge ASAP.<br />The really good charger $200 to $300 will messure tempature also and when cold may charge at a higher voltage than 14.8 but only when is good for battery.