120v LED vs CFL vs 12v Lamps Results

BFL13 wrote:

CA Traveler wrote:

DiskDoctr wrote:
So if I understand correctly, using 120v inverter is 1.7 amps + .5 amp for 120V LED bulb?

That was my take but he's posting DC inverter amps. Perhaps confusing since he's using a AC LED for his comparisons.

To clarify--

The LED case of a 2.2a DC draw was:
-0.7a standing parasite draw, plus
-1.0a with 3000w inverter on (which has a small standing load doing "whole house" from the 120v power centre circuit breakers-about 0.1a DC each) making that 1.7a draw before turning on the LED reading lamp.
- 0.5a with LED on (that is not all "light bulb"--it is in a socket on a wire circuit that has some R to it--your rig's circuit might have more or less load to it as seen by the inverter than ours.)

Depending on how your wire your inverter to the batteries, what inverter you use, and and how you power your LED light from the inverter (whole house through the power centre or ?), you can get different results from mine.

It seems some of those big inverter/chargers have much more no-load DC draw with all their display "features" etc, sucking power, than my simple inverter has, so the inverter-120v reading lamp trick would be more for a simple inverter I think.

The large high current output section of a inverter with excess overhead under a light load is the "killer".

Using a 3Kw inverter to power a half amp (60W at 120V) load will never be "efficient".

Inverter efficiency gets better when you start loading it closer to the output rating. That is where the idle current of the inverter output becomes extremely small compared to the power drawn by the 120V load.

Your inverter is consuming 22W at 13V, and if you add say a 1500W 120V load that 22W now essentially disappears..

My suggestion is to retry your measurements by using a much smaller inverter which 60W is closer to 1/4 - 1/2 the inverter wattage..

So, a 200W - 300W inverter would be a more suitable solution since most of those only have .250A - .500A idle current..