I have a 2,000 watt Invertor.. If I run an 32 watt fan, how many watts or amps is the 2,000 watt Invertor using from the 12 volt battery ?.

 

Hello,

The consumed power will be higher that the 32 watts of the fan alone.
The inverter will have an efficiency, most likely given in the documentation of the inverter.
An invereter can have an efficiency between 80 and about 90 %.
Lets assume an efficiency of 80 %, than the power taken from the battery will be 32 / 0.8 = 40 watts.

Bertus

 

The efficiency may be less for light loads. It depends upon the quiescent no-load current of the inverter.

 

Here's what I do. I connect a battery charger and note the current. Then I connect the inverter and load and take another reading. Subtract the first reading from the second and you know the current draw.