Testing 6v batteries

[Nwatkins176]

I am still new, and if this has been covered in the ID10T form already I am sorry.

But could somebody give me a testing your 6v batteries for idiots guide.  I know i need a volt meter and a hydrometer, and I am not sure even what a hydrometer is.  Do I have to disconnect each battery at a time when I test it?  Or can I leave it wired in when I put the voltmeter on it.  Thanks in advance

 

[Tom]

Here you go, an article in our forum library on battery charging basics. Includes voltage and specific gravity for various levels of charge. Divide the voltages by 2, because they're for a 12V battery.

 

[Brother Bear]

Best way is to get a load tester that has both a 6 volt and a 12 volt battery range on it.

 

[Tom]

I read the original post as a way to test the state of charge. If you're really trying to check if a battery will still hold its charge, then Larry's solution is the way to go.

 

[Gary RV_Wizard]

A battery hydrometer is a simple suction tube (like a turkey baster) that has a calibrated float inside to extract water from a battery cell and measure the specific gravity of the electrolyte in it. The Specific Gravity varies with the state of charge and the condition of the cell. You measure each cell separately.

http://www.amazon.com/E-Z-Red-S101-Battery-Hydrometer/dp/B000JFHMRU

http://www.ehow.com/how_4964575_use-battery-hydrometer.html

 

[John From Detroit]

First, Please do not think of "Six Volt Batteies" You should think of the two of them together as though they were one 12 volt battery, This answers nearly all the questions you have about six volt batteries  EXCEPT.. For the ones you specifically asked.

The kinds of questions it answers: If I replace one do I replace the other (Would you replace 1/2 of a 12 volt battery) Do they have to be the same age, size, type et-al, (Would you want a half & Half 12 volt?)  See how it answers questions.

I see Gary has described a Hydrometer, You get 'em at auto parts stores or auto departments,  There are 3 kinds

Floating ball (Junk)

Non-Temperature compensated (Useful but it is a whole lot of work)

Temperature compensated THE BEST.  This is the kind to get.

To use one you simply suck up a bit of fluid (Acid/water mix) out of the battery and read the floating blub (how high it floats) there is a scale inside it.


Voltmeters.. You need to have the batteries resting, That is no current flow, for at least 30 minutes for a true reading,  Simply use your disconnect, that will be close enough in most cases, No need for a wrency.

Again, measure the 12 volt voltage. don't worry abut each battery, treat the pair as a single 12 volt.

In the very rare case where you think you might need to know if they are properly "matched"  Well the proper voltages for a six volt are 1/2 those for a 12.

 

[Nwatkins176]

Those answers a huge help everybody.  I have neglected to do this because everything is working fine, but soon I will test the batteries.

 

[Jammer]

You can also remove the battery and take it to a battery place.  If in serious doubt as to the condition this might be the most straightforward way since you'll have to go through those steps anyway..