Battery disconnect question

[BradW]

Just wondered...I am going to install a battery disconnect. Was just thinking through all of it and it crossed my mind... what will happen if you have the battery disconnected and you plug into 30 amp. Would that do damage? Inessance it would be the same as plugging into 30 amp without having a battery. I'm guessing that, at best, certain things would not work inside because....I may be wrong here,,,, but are certain things not powered by 12 volt, even when plugged into 30A? Is it right that elect goes from 30 Amp service to your 12V charger and to your battery, then out to certain things that are 12 Volt only......or is that totally wrong thinking?

[wmtire]

Originally Posted by BradW

Just wondered...I am going to install a battery disconnect. Was just thinking through all of it and it crossed my mind... what will happen if you have the battery disconnected and you plug into 30 amp. Would that do damage? Inessance it would be the same as plugging into 30 amp without having a battery. I'm guessing that, at best, certain things would not work inside because....I may be wrong here,,,, but are certain things not powered by 12 volt, even when plugged into 30A? Is it right that elect goes from 30 Amp service to your 12V charger and to your battery, then out to certain things that are 12 Volt only......or is that totally wrong thinking?

Brad, when you are plugged into a 120 volt AC power source, then your converter is what powers most of the 12 volt DC stuff. The converter is also what recharges the battery too (but can't do this if the battery is disconnected).

This link may help you understand it better:

RV Converters and Amp Draw - RV Information (RV Maintenance)

and this flow chart:

[BradW]

Ahhhh Ok.... Totally makes sense.....Thank you.....learned something new today.

[RamblerGuy]

If you plug in the 30 amp shore line, the convertor will make the positive battery cable(s) hot, so if you do this, be sure to wrap them with tape or somehow insulate them.

Also, the flow chart posted by wmtire does not show the "Battery Control Center" that is in a motorhome. It is between the battery bank and the motorhome's alternator. It senses the voltage of both and energizes a relay that connects the two so the alternator can charge the battery bank or the convertor can charge the motorhome's battery when the respective system's voltage is high enough to do it without draining the system.