Well, I hate to be the bearer of bad news, but there is a pretty good chance that your 5th wheel did not come with a Power Inverter. Hopefully you are not confusing a Power Inverter with your 5th Wheel's Power Converter.
A Power Inverter takes the 12 Volt DC power from your RV's house batteries and transforms it to 120 Volt AC Power so you can use 120 volt powered items like laptop computer, TVs, etc. when you are not connected to external shore power or running a generator.
In the case of your 5th Wheel this may be an option that you did not get. Hopefully you have all of the original documentation for your trailer. In that documentation you should find a separate owner's manual for the inverter that may have been installed on your Fifth Wheel.
If you do not have one in your 5th wheel, don't despair as you can always buy a Power Inverter and install it in your fiver. Please read the answers that I gave to the questions below for further information.
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