Samlexpower SAM-1500C-12 Owner's manual - Section 4 |
18 | SAMLEX AMERICA INC.
NegativePostofthefirstbatterystring(Battery1ofBatteryString1asinFig.4.4),
the following abnormal conditions will result:
• Theresistancesoftheconnectingcableswillnotbebalanced.
• Theindividualbatterieswillseedifferentseriesresistances.
• Alltheindividualbatterieswillbechargedatdifferentchargingcurrentandthus,will
reach fully charged state at different times.
• Thebatterywithlowerseriesresistancewilltakeshortertimetochargeascomparedto
thebatterywhichseeshigherseriesresistanceandhence,willexperienceovercharging
and its life will be reduced.
Sizing inverter Battery Bank
Thefollowingbasicrulesareusedtodeterminethesizeofthebatterybank:
• ActivePowerinWatts(W)=
VoltageinVolts(V)xCurrentinAmperes(A)xPowerFactor ...................... formula 1
• Foraninverterrunningfroma12Vbatterysystem,
theDCcurrentrequiredfromthe12Vbatteriesisthe
AC power delivered by the inverter to the load in Watts (W)
divided by 10 ..................................................................................................... formula 2
• Energyrequiredfromthebattery=
DCcurrenttobedelivered(A)xtimeinHours(H) ........................................ formula 3
• AsaRuleofThumb,Ahcapacityofthebatteriesrequired=
2xEnergyrequiredfromthebattery ............................................................. formula 4
Anexampleofthiscalculationfora12Vinverterisgivenbelow:
Let us say that the total continuous ac Watts delivered by the 12V inverter = 1500W.
Then,usingFormula2above,theDCcurrenttobedeliveredbythe12Vbatteries=
1500W÷10=150Amperes.
next, the energy required by the load in ampere Hours (ah) is determined:
Forexample,iftheloadistooperatefor3Hours,thenasperFormula3above,theenergy
tobedeliveredbythe12Vbatteries=150Amperes×3Hours=450AmpereHours(Ah).
finally, as per rule of thumb at formula 4, the ah capacity of the batteries should be
twice the energy required by the load in ah=450Ahx2=900Ah.