How Many Batteries For a 3000W Inverter?

in this video I'm going to tell you how many batteries you need for a 3,000 WT inverter the answer might surprise you because most people get this wrong then I'll give you two examples for a lithium and a lead acid battery I often see people using a 3,000 W inverter on a 12vt 100 amp hour battery which amazes me no wonder the battery dies after half a year I'm going to talk about the battery voltage and capacity which are the most important factors when sizing your battery in an offgrid solar power system you should limit the current to 100 amps this has several reasons and benefits reduced wire cost cheaper charge controllers higher efficiency we can limit the current by increasing the voltage that means that for each battery voltage we can have a maximum inverter power range these are for 12vt battery inverters up to 1,000 Watts 24v battery inverters up to 2,000 WTS 48v batteries inverters up to 5,000 WTS if you want more power use a 48v battery with inverters in parallel I will calculate it for a 3000 watt inverter we divide 3,000 WTS by 48 volts to become 63 amps we then have to multiply by a safety factor of 125% to become 78 amps we need to use an 80 amp fuse this is under 100 amps so this is okay as already discussed an additional benefit is that the charge controller current will be decreased as you can see in the following calculation 800 W of solar power divided by a 12vt battery equals 66 amps we choose for a 70 amp charge controller but with a 48 volt system we can repeat the calculation and we will see that we only need a 20 amp charge controller this will be much cheaper to purchase now the second part of the calculation is a term called C rate every battery has a recommended C rate this is point 2 C for lead acid and 1 C for lithium this is a recommended charge and discharge current of a battery for example a 100 amp hour lithium battery should be charged and discharged at a maximum of 100 amps because 100 amp hours * 1 C equals 100 amps let's repeat the calculation for Le acid 100 amp hours * 2 C = 20 amps we can see that a lead acid battery can deliver significantly less current you can still pull 100 amps from a lead acid battery but the battery won't last very long because heat will be generated and degrade faster you also wouldn't be able to extract 100 amp hours because a lot of energy is lost in heat now back to the subject with an example for lithium batteries we already know we need a 48v battery next we need to calculate the current it will draw 3,000 W / 48 Vol equals 62.5 amps this is under the recommended discharge rate of a 100 amp hour battery which is 100 amps we need to use a 48 volt 62.5 amp lithium battery a 48v 100 amp hour server rack is an ideal example of a battery that is suited for a 3 Kow inverter you can also use several batteries wired together like 4 12vt 100 amp hours wired in series or two 24v 100 amp hour batteries in series there will be a link in the description to the lithium batteries I recommend now we will repeat the calculation for lead acid batteries we start by doing the same calculations 3,000 wats divided by 48 Vols equal 62.5 amps one 100 amp hour lead acid battery with a c rate of 2 C can deliver 20 amps next we divide the battery current by 20 amps 62.5 amps / 20 amps equals 3 we need three 100 amp hour batteries for a total capacity of 300 amp hours because 300 amp hours * 2 C = 60 amps we need a 48 volt 300 amp hour Le acid battery to effectively power a 3,000 W inverter this is three times the size than lithium and will weigh 1,000 compared to 110b for lithium a possible battery configuration is four 12vt 100 amp hour batteries in series and then paralleled with two other strings for a 4S 3p battery always charge batteries fully before connecting them together for lithium you need a 48v 100 amp hour battery and for lead acid you need a 48v 300 amp hour battery always respect the C rate of a battery to get the maximum lifespan thanks for watching like this video if you want more information like this are you confused about solar power get seven free solar diagrams through the pin comment below

Channel: Cleversolarpower

Views: 630,469

Keywords: off grid solar, 3000w inverter, off grid living, pure sine wave inverter, kings 3000w inverter, off grid solar setup, off grid solar power system for home, off grid solar power system, diy solar panel system, off grid solar inverter, off grid solar system installation

Id: -Zcn74IWlGQ

Length: 6min 9sec (369 seconds)

Published: Wed Dec 20 2023