Luisafernandes
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SternWake, very informative, thank you!
AGM BATTERIES
- Thread starter Luisafernandes
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There seems to be a wealth of information here. I don't want to hijack the thread but I would like to have someone who knows recommend what charger and AGM batteries to go with. And the difficulty in installing the set-up.
SternWake
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bobj, that is a lot of info to compile.
Odyssey has a small list of approved chargers.
http://www.odysseybattery.com/documents/ODYSSEYapproved12VchargersMay2013_000.pdf
NorthStar has a longer list which I cannot locate at the moment.
Fraid you will have to do your own research for other AGM's sizing the charger appropriately for the size battery bank and the acceptance/absorption voltages should be very close to the manufacturer recommended limits for best results.
Do note that RV Converters are like HD battery chargers that are not provided with alligator clips or carrying handles.
Iota, powermax and progressive Dynamics all make various amperage chargers which can act as 12v nominal power supplies, 3 stage charging the batteries whilst powering all DC loads.
Regular portable chargers will get confused and shut off when trying to power dc loads while charging the batteries.
Odyssey has a small list of approved chargers.
http://www.odysseybattery.com/documents/ODYSSEYapproved12VchargersMay2013_000.pdf
NorthStar has a longer list which I cannot locate at the moment.
Fraid you will have to do your own research for other AGM's sizing the charger appropriately for the size battery bank and the acceptance/absorption voltages should be very close to the manufacturer recommended limits for best results.
Do note that RV Converters are like HD battery chargers that are not provided with alligator clips or carrying handles.
Iota, powermax and progressive Dynamics all make various amperage chargers which can act as 12v nominal power supplies, 3 stage charging the batteries whilst powering all DC loads.
Regular portable chargers will get confused and shut off when trying to power dc loads while charging the batteries.
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Sternwwake,
I'm just charging off my solar and my batteries never get that high a charge rate. So one of the best things I could do for my batteries is to buy this 55 amp charger and run it off my Honda when it gets low?
http://www.solar-electric.com/ioten55amp12.html
Is that true as well for my flooded golf carts? Do you have a better recomendtion for a charger that will run off my Honda 2000?
Bob
I'm just charging off my solar and my batteries never get that high a charge rate. So one of the best things I could do for my batteries is to buy this 55 amp charger and run it off my Honda when it gets low?
http://www.solar-electric.com/ioten55amp12.html
Is that true as well for my flooded golf carts? Do you have a better recomendtion for a charger that will run off my Honda 2000?
Bob
SternWake
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Bob, GC batteries are pretty tolerant of most bulk charge rates.
Depends on who makes the GCs as to what they like in terms of minimum bulk rate and acceptance voltage. I've not owned GC's personally.
I do believe an occasional high charge rate after a deep cycle is advantageous to all lead acid batteries, except for gel batteries and those AGMs which say to limit recharge current to no more than 30%, but 30% is still pretty dang high. A hundred watt panel on a hundred amp hour battery is barely 5%, and AZ wind and Sun forums recommends a 5 to 13%, so you see many solar systems might be able to replace the amp hours used by the owner, but not nearly at the rate the batteries desire.
I'd recommend getting a good Hydrometer and see how high the specific gravity rises when "fully charged" by the solar.
GC's need the occasional equalization charge too. After a proper EQ charge cycle you will see the maximum SG levels and consider this your baseline.
If your BlueSky Solar controller allows you to run an EQ cycle, or you can adjust the voltage setpoints up this high, disconnect the batteries from electrical loads, and crank it up to 16 volts. Take SG measurements every 15 minutes or so, until the SG no longer rises or battery temperature starts rising quickly or exceeds 120f. Should be in the 1.275 to 1.290 range and one hopes all are cells are within 0.010 of each other or better. As electrolyte levels drop the SG will get denser and read higher when fully charged, after refilling it, it will read lower when fully charged. Expectations of a fully charged battery should be raised or lowered with the level of the electrolyte.
Note that as the electrolyte warms the SG number will lower on the float but when compensated for temperature, might still be rising. The middle cell/cells might be warmer than the outside cells. Give many bulb squeezes to both mix the electrolyte and allow the thermometer to register the actual electrolyte temperature and to actually make sure no Bubbles are sticking to the float, which will throw off readings by 0.005, easily, per bubble.
So A hydrometer with a thermometer on it which tells you how much to add or subtract is superior.
http://www.amazon.com/OTC-4619-Professional-Battery-Hydrometer/dp/B0050SFVHO
Supposedly the Francis Freas Hydrometers are the top dog in both accuracy and precision.
http://www.freasglass.com/battery.htm
I have a Bluesku 2512i charge controller and the BlueSky IPN pro remote Monitor. The latter product allows me to change voltages. I believe it works with all Blue Sky products.
I think the 14.8v ABSV of the Iota makes it one of the better charger/ converters for flooded batteries, especially those which specify more than 14.4v.
The Powermax converters in the 75 amp+ versions are power factor corrected and can run off of standard 15 amp outlets. But are only 14.4 or 14.6Vabs. If you have more than two GC's you can really pump them full of Amps in the morning for a half hour, or however long you fire up the Genny for, and then let the solar take over, and see if SG readings near sundown are higher than if the solar by itself took the batteries to blinking green light stage.
Your GCs might be happy with just the solar, the Hydrometer is the best tool to discern this, but you need to have a way to give the batteries an EQ charge cycle to see how high the SG can get, to to see if the solar is doing a good job or not.
Depends on who makes the GCs as to what they like in terms of minimum bulk rate and acceptance voltage. I've not owned GC's personally.
I do believe an occasional high charge rate after a deep cycle is advantageous to all lead acid batteries, except for gel batteries and those AGMs which say to limit recharge current to no more than 30%, but 30% is still pretty dang high. A hundred watt panel on a hundred amp hour battery is barely 5%, and AZ wind and Sun forums recommends a 5 to 13%, so you see many solar systems might be able to replace the amp hours used by the owner, but not nearly at the rate the batteries desire.
I'd recommend getting a good Hydrometer and see how high the specific gravity rises when "fully charged" by the solar.
GC's need the occasional equalization charge too. After a proper EQ charge cycle you will see the maximum SG levels and consider this your baseline.
If your BlueSky Solar controller allows you to run an EQ cycle, or you can adjust the voltage setpoints up this high, disconnect the batteries from electrical loads, and crank it up to 16 volts. Take SG measurements every 15 minutes or so, until the SG no longer rises or battery temperature starts rising quickly or exceeds 120f. Should be in the 1.275 to 1.290 range and one hopes all are cells are within 0.010 of each other or better. As electrolyte levels drop the SG will get denser and read higher when fully charged, after refilling it, it will read lower when fully charged. Expectations of a fully charged battery should be raised or lowered with the level of the electrolyte.
Note that as the electrolyte warms the SG number will lower on the float but when compensated for temperature, might still be rising. The middle cell/cells might be warmer than the outside cells. Give many bulb squeezes to both mix the electrolyte and allow the thermometer to register the actual electrolyte temperature and to actually make sure no Bubbles are sticking to the float, which will throw off readings by 0.005, easily, per bubble.
So A hydrometer with a thermometer on it which tells you how much to add or subtract is superior.
http://www.amazon.com/OTC-4619-Professional-Battery-Hydrometer/dp/B0050SFVHO
Supposedly the Francis Freas Hydrometers are the top dog in both accuracy and precision.
http://www.freasglass.com/battery.htm
I have a Bluesku 2512i charge controller and the BlueSky IPN pro remote Monitor. The latter product allows me to change voltages. I believe it works with all Blue Sky products.
I think the 14.8v ABSV of the Iota makes it one of the better charger/ converters for flooded batteries, especially those which specify more than 14.4v.
The Powermax converters in the 75 amp+ versions are power factor corrected and can run off of standard 15 amp outlets. But are only 14.4 or 14.6Vabs. If you have more than two GC's you can really pump them full of Amps in the morning for a half hour, or however long you fire up the Genny for, and then let the solar take over, and see if SG readings near sundown are higher than if the solar by itself took the batteries to blinking green light stage.
Your GCs might be happy with just the solar, the Hydrometer is the best tool to discern this, but you need to have a way to give the batteries an EQ charge cycle to see how high the SG can get, to to see if the solar is doing a good job or not.
SternWake
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Bob, just remembered you have Full river AGM GC's, so no hydrometer for you.
Check out this page:
http://www.fullriverdcbattery.com/technical/charging/
Here is my SG just about maxed out:
It is reading 1.280+ on the Float, and the thermometer sad to add 5, so this cell is around 1.2875.
This group 31 USbattery is a true 12v deep cycle rated at 130 Amp hours, and It is a petulant battery which requires abnormally high voltages.
Even after a week of 14.8v Absorption for about 2 hours, and a 15.1v Finishing charge, the SG will only read in the 1.265 to 1.270 after a "full charge"
I need to apply 45 minutes or so of 16v to get the battery upto thee 1.285.
Seems these large flooded 12v jars are all kind of peculiar in this matter. The GC batteries do not need these intense voltages nor the weekly EQ from what I read on other forums.
USbattery wants a 10% bulk rate for my battery( 13 amps). My solar can just meet this number in summer, but subtract for the fans and the cycling fridge and other loads and I fall short on the 198 watts of solar.
Check out this page:
http://www.fullriverdcbattery.com/technical/charging/
Here is my SG just about maxed out:
It is reading 1.280+ on the Float, and the thermometer sad to add 5, so this cell is around 1.2875.
This group 31 USbattery is a true 12v deep cycle rated at 130 Amp hours, and It is a petulant battery which requires abnormally high voltages.
Even after a week of 14.8v Absorption for about 2 hours, and a 15.1v Finishing charge, the SG will only read in the 1.265 to 1.270 after a "full charge"
I need to apply 45 minutes or so of 16v to get the battery upto thee 1.285.
Seems these large flooded 12v jars are all kind of peculiar in this matter. The GC batteries do not need these intense voltages nor the weekly EQ from what I read on other forums.
USbattery wants a 10% bulk rate for my battery( 13 amps). My solar can just meet this number in summer, but subtract for the fans and the cycling fridge and other loads and I fall short on the 198 watts of solar.
