Help, don't understand how the 12v system works.

[volcomig]

Hi, I am new to motorhomes and to this forum. I just bought an old ford econoline conversion campervan converted by van am era. My electrical accessories are the following: Fridge, propane heater (fan) and lights. These are connected to my auxiliary battery (I have 2 batteries). I have some 12v switch in the camper indicating on/off. When the engine is on, working no issues everything works, but I thought that if I plugged my camper in a house electrical outlet and turn that camper's 12v switch on, all the accessories would work endlessly. But no it is not related to the accessories. All that switch does is activate two outlets that are in the camper. There must be a way to plug the camper and make all the accessories work!! An extension cord with a power bar would do the same as that 12v switch. Just so you know the plug connect my van is a regular house size. 15 amps I assume. Please educate me.

[924guy]

Traveler7 wrote:

If your setup is similar to my van conversion 'HOUSE' switch is used when you are connected to city power and takes 12 volt out of the circuit, activates the charger, and powers any 120 volt outlets you have. At least that's how mine works.....

Hope this helps and apologize in advance if I misunderstood you!

it is possible, but if so, then i have another problem as my 12v system will not energize with the switch in any position when . it only powers on when hooked into 120v (with the switch in either position,) or if i jump out the switching circuit by bridging the coil relay near the house battery.. very odd.

[Traveler7]

(((((((Hi all,

Im going to jump in here as I am also in the same situation as the original question describes, and still trying to trace our the issue. Our answers may be related.

In my van (92 Dodge Ram Van 3500 series converted by the now defunct Coachmen conversions division) the "house" power switch does absolutely nothing that i can tell. I have two 12v transfer coils (one front battery, one rear battery) that ive replaced with new along with their in line breakers as i suspected that was the issue (and was part, one breaker tested bad) but still didnt give me power to the "house." the "house" 12v works on 120 and works if i jump out the rear coil, but no other way. the converter appears good. the brand new transfer coil isnt opening with the 12v house switch like i expected.. all the breakers and fuses (ive yet found) are good or have been replaced.
Im going to try (again) and trace out the path of the house 12v switch, and see where it feeds from. are these things truly random or is there a general location where it can "usually" be found to feed from? all the wiring for this is hidden so any experienced tips will be helpful. )))))

If your setup is similar to my van conversion 'HOUSE' switch is used when you are connected to city power and takes 12 volt out of the circuit, activates the charger, and powers any 120 volt outlets you have. At least that's how mine works.....

Hope this helps and apologize in advance if I misunderstood you!

[924guy]

Hi all,

Im going to jump in here as I am also in the same situation as the original question describes, and still trying to trace our the issue. Our answers may be related.

In my van (92 Dodge Ram Van 3500 series converted by the now defunct Coachmen conversions division) the "house" power switch does absolutely nothing that i can tell. I have two 12v transfer coils (one front battery, one rear battery) that ive replaced with new along with their in line breakers as i suspected that was the issue (and was part, one breaker tested bad) but still didnt give me power to the "house." the "house" 12v works on 120 and works if i jump out the rear coil, but no other way. the converter appears good. the brand new transfer coil isnt opening with the 12v house switch like i expected.. all the breakers and fuses (ive yet found) are good or have been replaced.


Im going to try (again) and trace out the path of the house 12v switch, and see where it feeds from. are these things truly random or is there a general location where it can "usually" be found to feed from? all the wiring for this is hidden so any experienced tips will be helpful.

thanks,
eric

[Oldme]

A good interactive link.
Use the links on the left to see how
things work under different situations.

http://www.metrotrekkers.org/utility/electrical.htm

[stan909]

You guys nailed it.

[Dennis_M_M]

This is a good place to start: The 12 Volt Side of Life

[volcomig]

Ok I understand perfectly, thanks guys.

[turbojimmy]

I forgot to mention, too, that some converters will not work through a bad battery. Make sure both of your batteries are in good shape.

[naturist]

There is a way to make all the 12 volt stuff work endlessly when on shore power, but it requires a device called a converter. Your Econoline conversion might or might not have one. And if it does, it might not be working.

It is the function of the converter to recharge your house battery (not your starting battery, however) from shore power and to manage the 120 volt and 12 volt systems. It is usually where the fuses/circuit breakers for everything are located.

[RoyB]

This is a typical 30AMP Power Distribution configuration for RV Trailers.. The Motorhome types are similar but have different control items.



Roy Ken

[turbojimmy]

Not sure how yours is set up, but nearly all motorhomes act as you've described. Nearly everything that can possibly be 12V is 12V. Lights, fridge, water pump, etc. Things that absolutely have to be 120V for practical purposes are 120V. Things like air conditioners and, as you've found, 120V outlets.

You have 2 batteries. Typically one is to start the engine and doesn't do much else. The other will be for the "house" - all those previously mentioned 12V things. When the engine is running, it should charge that 2nd battery. When plugged into shore power, a CONVERTER should convert the 120V AC to 12V DC and provide continuous 12V power to your "house" (and charge that 2nd battery).

So....look for a converter and make sure it's working. They're usually protected by a circuit breaker on the 120V side. Look where your power cord enters the RV and follow it to (hopefully) a breaker box and ultimately to a converter. There should also be a 12V fuse panel for the house that you can trace back to a converter somewhere.