I have been charging 12 batteries at once for a couple days at 10 amps. Now it's time to test them. The charge is at 12.87 volts on the batteries. I have a load tester here and tested the first battery and it was in the green. Had to take a potty break. Do I just hit the button for a few seconds or do I need to hold it down for a while?
no need to reply, I just tested the batteries and out of 12, 11 were still ok to use. one battery went into the yellow so I'm leaving it out, all the rest stayed in the green (just barley) but good enough for me. I hope to get another year out of them.
Quote from: Charley Davidson on October 26, 2007, 09:40:23 AM
no need to reply, I just tested the batteries and out of 12, 11 were still ok to use. one battery went into the yellow so I'm leaving it out, all the rest stayed in the green (just barley) but good enough for me. I hope to get another year out of them.
They are not fully charged yet, either. At that low a charge rate for that many batteries it will take at least a couple of more days to get them up to charge. Open cell voltage should be about 13.5 to 13.8 volts.
Richard
seems these batteries will only charge to 12.87 volts then the smart charger says full. ???
Quote from: Charley Davidson on October 26, 2007, 10:58:07 AM
seems these batteries will only charge to 12.87 volts then the smart charger says full. ???
Something wrong then. 12.87 volts equates to 2.145 volts per cell. Full charge on a cell is 2.25 volts equals 13.5 volts.
Richard
BTW, NAPA sells an electronic battery tester for less than $100. I guarantee that it works 100% and I have had thousands of batteries checked with this unit and never found it to be wrong. A very worthwhile investment for anybody.
Richard
Hi Charley,
When you get the bad bat out of the group ,
charge them again and see if the voltage then
goes up to full ( 13.8 VOLTS ).
Keep taking the bad bats out until the final group charges up.
Then you'll know they are all good ones.
Frank
Quote from: Charley Davidson on October 26, 2007, 10:58:07 AM
seems these batteries will only charge to 12.87 volts then the smart charger says full. ???
Ron the guy at the battery shop explained it best to me once by telling me "that in order to bring them back to a proper state of charge they needed to be charged seperately with a high amp charger min. 24 ea (stating that if they don't need the high amps, they'll only draw what they NEED but it needs to be there in case needed) but he said slow charging them just puts a surface charge on them not a saturated charge". He said "it's like baking a cake in the oven. If the oven is not hot enough, then the cake will not be done in the middle! So if the charge is not (HOT) enough the battery plates will not be charged in the middle!"
Hey sounded right to me, and thats the way I now charge my battery's and hardly ever have a problem with one other than letting the get low on charge from leaving something on or not starting the unit (ya know the Setra that Mike's mattresses are in! LOL!) for long periods (months) of time!
But hey remember this is your gig, do it your way I just thought I'd try to edjumacate you as the battery guy did me! boy am I all charged up with no place to go!.
I just charged one by it's self and that was the result. I'm going to charge with a regular battery charger and see what happens. Also I have a recondition battery feature on my smart charger it takes 24 hrs to recondition a battery. Exactly what is this and is it worth doing?
Hi Ron,
It's doing just that, Deep charging the batteies. The weak battery will always bring the whole bank down so get rid of it.
After long pieroids of batt use, the charging system wont always recoupe to normal state so, bulk charging is recommended
on a monthly cycle to maintain optimum charge state. If they are lead acid, use a hydrometer to test all cells for equality.
If AGM, a load tester is all you need but, you have to have an accurate reading from it.
Good Luck
Nick-
"Also I have a recondition battery feature on my smart charger it takes 24 hrs to recondition a battery."
Depends exactly what it is. If it is a manually operated conventional equalization cycle then it may not be recommended for your AGM batteries.
Battery manufacturers recommend a bulk charge cycle that takes the battery up to 14.4 volts to get a full charge.
A load tester will give a reasonable idea of the battery's ability to deliver a high current for a short time but you need to check the tester instructions because the load resistor will likely not be continuous rated.
What do you mean by bulk? Charge at a higher rate like 40 amps?
Quote from: Charley Davidson on October 27, 2007, 12:01:29 AM
What do you mean by bulk? Charge at a higher rate like 40 amps?
I believe the more proper term is an
equalize charge and yes it is at a higher amp rate.
The charging amps are fully controlled by the applied voltage of the charger and an equalize charge is generally in the 15 volt or higher range for a period of time. The battery should bubble some and you will lose some liquid, but the charge is to equalize all the cells in the individual battery.
I strongly urge you to visit the Help board and read the Battery articles posted there. Lots of good information from the experts.
Richard
"What do you mean by bulk? Charge at a higher rate like 40 amps?"
No, I used that term for the first part of the normal 3-stage charge cycle. Bulk, Absorption and Float.
Equalisation is a fourth stage - usually manually initiated but sometimes automatically done every 25 cycles --that goes to a higher voltage again - maybe 15V - for a strictly controlled period.
Many AGM and other sealed batteries shouldn't be subjected to an equalisation charge, but flooded cell batteries do benefit from it provided the operator is aware of the reasons for and possible results of carrying it out.