power inverter and battery capacities

Discussion in 'General Electronics Chat' started by moonspell, Nov 15, 2008.

  1. moonspell

    Thread Starter New Member

    Nov 15, 2008
    Hello. I am considering buying a 100w inverter and connecting it directly to my 2.3Ah 12V Lead-acid battery through alligator clip cables. My question is whether there is a minimum battery capacity, bellow which the inverter wont work, (for example, would my battery power a 100w inverter or would there be adverse effects due to it not having a high enough Ah rating?) I'd be using the inverter to power a 10w compact florescent bulb for 1hr daily. the battery is recharged using a solar panel. Also what cable gauge would be recommended to connect the 100w inverter to the battery? Thanks
  2. bertus


    Apr 5, 2008

    Sorry, my calculations where wrong, follow sgt wookie
  3. SgtWookie


    Jul 17, 2007
    OK, let's assume that the 100w inverter will be around 80% efficient.
    10W from 12.6v at 80% efficiency will be just about 1A current flow (992mA) on the 12.6v side, discharging the battery about 43%.

    Your battery life would be improved considerably if you only discharged it 30%; use a 3AH or larger battery.

    Keep the wires from the inverter to the battery short relative to the 120VAC side. While the DC current will be about 1A, the AC current will only be 83.3mA.
  4. Bailey45


    Oct 27, 2008
    Your circuit will operate better if you do not used alligator clips. A ring or spade connector is a much better idea. The loss on this connector will have a greater effect that the length of wire from source to load.