zulu4 wrote:What tipe of battery bank do you need for example 3000watt.
To produce 3000W from an inverter running off a 12V battery would require 250A ! (A=W/V), this is assuming 100% efficiency, if you are lucky you will get about 85-90%.
So, running from a "normal" car battery, lets say 65AH, you won't provide more than 15 minutes of power at 3000W (You have a good chance of boiling the battery !)
Even a 105AH, deep cycle battery would give you less than 25 minutes.
Inverters are magic, I have a 2800W sine wave inverter but make no mistake, you need plenty battery capacity. My inverter runs from a bank of 8 x 105AH deep cycle batteries, the batteries are kept charged under normal circumstances by a 14A solar panel or by a 6.5KVA generator.
Let there be light :D
Rudi