4/21/2015 Amps,Watts...

http://www.simplesolarsetup.com/battery4.html 1/3

AmpHours(AH)Thevolumeofelectricity,capacity.A batterys storage capacity is measured in amps or amp (ampere)hours. One amp equals one hour of use without recharging or, inpractical terms,how longyoucanusepoweronadark, rainyday.Alldeep cyclebatteriesare rated inamphours supposedly, although Ivenoticedthelessexpensiveonessometimesdontwanttomentionitortheyuseanotherratingmechanismhavinglittletodowith it(moreonthatbelow).Asageneralstatement,higherendbatterieshavehigheramphourrates.Functionally,itsawayforyoutogaugehowlongyoucanusethatbatteryataknownusagelevelwithoutrechargingit.Thehigher theamphour rating, thebigger thebattery.Youneed toguessyour level of use in amps orwatts (see below) for any of it tomakesense.

Togiveyouanideaoftheamphourdifferencesinbatteries,alowerendbattery may have a 34 amp hour capacity and a high end fabulousbattery could have over a 400 amp hour capacity. There are lots inbetween.Thecostassociatedwitheachofthesebatteriescanbewildlydifferent.Ofcoursetheissueis,whatdoyouneed?Anotherissuemaybe,whatcanyouafford?WattsTheamountofelectricity.Wattsaremoreoftenassociatedwithaconsumingdevicethanamperes(amps)asinyourlightbulbhashowmanywatts?Youdontoftenhear,so,yourlightbulbhashowmanyamps?Its helpful to know/guess how much electricity you might consumewhenyouretryingtomakedecisionsaboutbatterysize.Sincebatteriestypically measure storage capacity in amps and consuming devicestypicallyinwatts,youmightwanttochangetheamphourmeasurementassociatedwiththebatteryintowatthoursasitbecomesmorelikeanorangestoorangescomparison.Asoneampequalsonehourofuse,onewattalsoequalsonehourofuse.Todo thisyoucanchange theamphourmeasurementassociatedwithabatteryintowatthours.Theequationforfindinghowmanywatthoursareavailableinabatterywhentheamphoursareknownisvoltagexamphours.Forinstance,a12volt105amphour(AH)batterycansupply1260watthours(12voltsx105amphours=1260watthours).Thatsat100%dischargewithoutpumping in new energy (whichmeans, if you actually do that, youvelikelyruinedyourbatteryyoushouldntgolowerthan80%with50%beingbetter).So,atsaya50%dischargeitscapacitymightbecloserto630watthours(1260dividedby2).Again,thegeneralequationiswattsequalvoltsxamps.

THE BATTERY

Home

SiteMap

Batteries

BatteryTypes

BatterySize

Amps,Watts...

BatteryFacts

SolarPanels

SolarPanels2

Controllers

Controllers2

Inverters

Inverters2

Wiring

Wiring2

FinalThoughts

MySetup

Resources

SolarNews

AMPS, WATTS, VOLTS

http://www.simplesolarsetup.com/chargecontrollers.htmlhttp://www.simplesolarsetup.com/mysolarsetup.htmlhttp://www.simplesolarsetup.com/solarnews.htmlhttp://www.simplesolarsetup.com/solarresources.htmlhttp://www.simplesolarsetup.com/wiring2.htmlhttp://www.simplesolarsetup.com/index.htmlhttp://www.simplesolarsetup.com/solarpanels.htmlhttp://googleads.g.doubleclick.net/aclk?sa=l&ai=CYeXrhNg0VZizLsaNogOVv4GAA92R3I4G5b-HmvYBwI23ARABIPbUziRg5fLng9QOoAG7nbbXA8gBAagDAcgDwwSqBKABT9DCCquGXM13zBoS_TxvDKYbLjEkMfCSaGTEol1qbB4oiMf2zg-UcRnuK2QBrx1Ol4QEq_7uRAvCiq6c8sk-41jPwTYl7UmBY-TPC6KmZpJUM-SF20NDfAG7TfK7jLtlXZ2C8B7SzXmI55X_tYTldNELICz3NtCpYNd2Qt8lrySSx-baliZZHtFVeiek55AnjZuhtuQpiL8Be4K0joxgqYAHreLJKKgHpr4b2AcB&num=1&sig=AOD64_15RTnwH3dDw17oKw4W8QU79C5Zwg&client=ca-pub-9433181236952314&adurl=http://trojanbattery.mv.treehousei.com/Surveys/12/31F54BC69593DABE/Survey_reskin.aspxhttp://googleads.g.doubleclick.net/aclk?sa=l&ai=CYeXrhNg0VZizLsaNogOVv4GAA92R3I4G5b-HmvYBwI23ARABIPbUziRg5fLng9QOoAG7nbbXA8gBAagDAcgDwwSqBKABT9DCCquGXM13zBoS_TxvDKYbLjEkMfCSaGTEol1qbB4oiMf2zg-UcRnuK2QBrx1Ol4QEq_7uRAvCiq6c8sk-41jPwTYl7UmBY-TPC6KmZpJUM-SF20NDfAG7TfK7jLtlXZ2C8B7SzXmI55X_tYTldNELICz3NtCpYNd2Qt8lrySSx-baliZZHtFVeiek55AnjZuhtuQpiL8Be4K0joxgqYAHreLJKKgHpr4b2AcB&num=1&sig=AOD64_15RTnwH3dDw17oKw4W8QU79C5Zwg&client=ca-pub-9433181236952314&adurl=http://trojanbattery.mv.treehousei.com/Surveys/12/31F54BC69593DABE/Survey_reskin.aspxhttp://www.simplesolarsetup.com/batteries2.htmlhttp://www.simplesolarsetup.com/battery4.htmlhttp://www.simplesolarsetup.com/battery3.htmlhttp://www.simplesolarsetup.com/batteries.htmlhttp://www.simplesolarsetup.com/solarsummary.htmlhttp://www.simplesolarsetup.com/battery5.htmlhttp://www.simplesolarsetup.com/solarpanels2.htmlhttp://www.simplesolarsetup.com/wiring.htmlhttp://www.simplesolarsetup.com/sitemap.htmlhttp://www.simplesolarsetup.com/inverters2.htmlhttp://www.simplesolarsetup.com/controllers2.htmlhttp://www.simplesolarsetup.com/inverters.html

4/21/2015 Amps,Watts...

http://www.simplesolarsetup.com/battery4.html 2/3

Going along with the example above, lets say your very safe 50%capacity allows that 630 watt hours of total usage mentioned above.Lets further say thatmaybe the biggest or longest inuse consumingdeviceyouwanttorunisyourportablecomputeranditconsumesabout95 watts an hour (look on the label). 630 total watt hours safelyavailabledividedby95wattsusedperhour=6.63hoursusagewithnoincoming battery charge. (Although its good to know even cloudy orrainydaysprovidesomeelectricalcharge.)

Ifthatsalongenoughusetimeforyou,thenperhapsinourexample,a105amphourbattery is big enough for yourneeds. In reverse,wattsdividedbyvolts=amps.Or,1260watthoursdividedby12volts=105amp hours, or using our 50% example, 630watt hours divided by 12volts = 52.5 amp hours available. How many amps does a portablecomputerdraw?Ithinkmineisaround7or8ampsperhour.52.6amphoursdividedby8equals6.56amphours.So,whetheryoucomparebyamp hours or watt hours the actual usage time comes out about thesame. Comparing usingwatts is just a bit easier because thats whatconsumingdevicestendtocomein.Theamphoursizeofyourbatterymatters.Onthevery lowend,a34amp hour battery might be fine if you have strong solar panel input,shorttermusewhichallowsforbatteryrecoverytimegoodsunwithnobatterydrain,oryoudontgetmanyrainydayswhereyouare.DifferentMeasurementConversionsforaBatteryDeepCycleBatteriesaremeasuredinamphoursandthenumberofamphours will be listed on it, on the better batteries anyway, or at leastavailable.

Thefollowingisofferedbywindsun.comassomeapproximateamphourratingsforexplainingsomeidentifiersthatappearonbatteriesinsteadofamphours.Withoutthisguessworkontheirparttheseidentifiers, likeGroup24(whatsthatabout),arentveryhelpful.

IdentifierAmphourestimateVolts

U134to40amphours12volt

Group2470to85amphours12volt

Group2785to105amphours12volt

Group3195to125amphours12volt

4D180to215amphours12volt

8D225to255amphours12volt

Golfcart180225amphours6volt&T105

SomeGoodtoKnowBatteryFactsPage5

TrojanBatteryIndiaAuthorizedTrojanDistributorIndiaBuyDirect&Save!

http://www.simplesolarsetup.com/battery5.htmlhttp://googleads.g.doubleclick.net/aclk?sa=L&ai=CD5PfhNg0VbSBLtaaoAPUgYHgCbL62uMH8pLS1XPAjbcBEAEg9tTOJGDl8ueD1A7IAQGoAwHIA8MEqgSZAU_QZok4fQ6mAmbrMFXUjTZnOwraGJGTxym8w0kt3lsVOcgVyukyi5wack9jRiffXhkFzApfFbzGOlL7olalWqKhckbFJmyvOmjmg-1VdmYCWB38-gUbw5z9D99tksE7zDIyTdPQ73IV7z4uAHzw1fwYJvzh7hRgUP5IRlLwt9d55UAdO7AAiUw35pffAVw7DldZUiTPNKpYjIAHoo7WIagHpr4b2AcB&num=1&sig=AOD64_2jPw2lxk00fLivsj6PlZQ5YW3hGA&client=ca-pub-9433181236952314&adurl=http://www.jmida.com/batterytester.asphttp://googleads.g.doubleclick.net/aclk?sa=L&ai=CD5PfhNg0VbSBLtaaoAPUgYHgCbL62uMH8pLS1XPAjbcBEAEg9tTOJGDl8ueD1A7IAQGoAwHIA8MEqgSZAU_QZok4fQ6mAmbrMFXUjTZnOwraGJGTxym8w0kt3lsVOcgVyukyi5wack9jRiffXhkFzApfFbzGOlL7olalWqKhckbFJmyvOmjmg-1VdmYCWB38-gUbw5z9D99tksE7zDIyTdPQ73IV7z4uAHzw1fwYJvzh7hRgUP5IRlLwt9d55UAdO7AAiUw35pffAVw7DldZUiTPNKpYjIAHoo7WIagHpr4b2AcB&num=1&sig=AOD64_2jPw2lxk00fLivsj6PlZQ5YW3hGA&client=ca-pub-9433181236952314&adurl=http://www.jmida.com/batterytester.asp

4/21/2015 Amps,Watts...

http://www.simplesolarsetup.com/battery4.html 3/3

20112015CopyrightBenjaminAssociates,LLC.AllRightsReservedContactUs

BatteryTestingSystemsFullBatteryTestingSolutionsCustomerDesignedEquipments

mailto:info@simplesolarsetup.com