[quote author=napalm204]
What I have discovered is that much of the electrical "stuff" you might want to use will not work unless the battery disconnect (or house batteries) are engaged. Although it is second nature to these guys on this site, I found that a bit odd when I first got my motorhome because it is not anything I had experienced before. I have always found a master switch of some description somewhere on the dash on all vehicles I have been around until I got my motorhome. For instance, my stereo switch mounted on the dash, will not energize my stereo unless the battery disconnect is engaged.[/quote]
The terminology can be confusing. The switches should, more properly, be labeled
Battery Connect switches.
ON meaning
Battery on or connected and
OFF meaning
battery off or disconnected.
You actually have several sources of electricity and options to use. Shore power; generator power; and 12-volt power. I have actually found that a motorhome is a pretty complex piece of equipment and it takes some time to get accustomed to its facets.
Shore power and Generator power can be considered the same (
once it enters the motor home) as it activates all the same 120vac appliances and fixtures through the same wires and components. (Inverters are an RV-102 subject)
Shore power also plays an important role in the 12 volt side of things as it powers your converter/battery charger to produce 12vdc. Most, if not all, of your
interior lights and
appliance control boards are powered by the 12 volt converter and/or the house batteries.
Activating the house battery
disconnect, with shore/gen power connected, will generally prevent the batteries from being charged, but
will not prevent the converter from continuing to power other 12vdc requirements. However, when shore/gen power is removed, while the disconnect is activated, the battery has no path to power the 12vdc circuits and nothing works. With no external power, the battery must be ON (activated).
And remember.... the RV generator will charge your house batteries and the engine alternator will charge your chassis battery.
Here's were generalizations can get one into trouble. As a rule, your statement is correct, but by no means complete.
Most coach manufacturers have installed circuits to charge the
house batteries, along with the
chassis batteries, from the
alternator.
Several have installed the capability to charge the
chassis battery, along with the house batteries, from the
converter. (shore/gen powered)
The method of implementation and operation varies widely from manufacturer to manufacturer. There are also myriad after market products and solutions to effect cross charging and battery isolation functions that us RVers perceive as problems or short comings.