Lee, Assuming I read the conditions properly, if you have no AC input, the inverters are "on" and you turn on a 120V lamp you created a DC load.

The inverters are taking DC power from the battery (hence the load) and converting it to AC to light the lamps.

All our buses are slightly different, but another thing to consider is we have "phantom" loads. I have no clue what they all might be in my coach, but I know they exist. With every switch and device turned off (not the big master switches, but switches that control specific items) I still have a current draw such as the alarm systems, computers, radios, clocks, intercom, cell phone, etc.

I don't know how our displays are set up. I assume the DC load meter shows only that which is passing through the inverter and that the "phantom" loads only show up when the battery charger is functioning by displaying AC amps when all AC devices are turned off.

What we need is for the major converters to put on overview seminars so we can understand the general concept of how our coaches are set up. I imagine each converter is slightly different.