System explanation for dummies - me

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Feb 27, 2011
Hi guys, y'all have been very helpful here, and I have another question, prolly a series of 'em. Short explanation here is the rig in my avatar is my "camper". I bought it to haul all my "stuff" to our new home. I have lots of "stuff" and too much if you ask my wife. Being a do it your self type and also cheap, I've been hauling loads on my 28' GN flatbed trlr. 650mi each way. The toterhome is for my wifes comfort and to avoid the scales and fuel sticker stuff. (I am NOT for hire and am hauling my personal prop. and do have a class A CDL)
I've never had a camper and I am the 3rd owner of this thing and there are no instructions on operating the diff. systems. I have tried to contact "United Specialties" the builder, with no luck. Right now, I'm trying to figure out the "house" battery sys. and when they charge. I'll start with a pic. of a switch that is in the same cabinet as the (2) house or coach battreies. I am looking for an explanation for the switch positions please.
A few more easy questions;
1 should these batteries charge when plugged in to "shore" power?
2 does switch position matter    "        "                        "          "        ?
3 does the truck motor provide  "house" charging?
4 should the (onboard diesel) generator charge them?
I'm getting ready to make another trip (alone) so I'm not too worried about having everything working, but I would like to run the propane heater during sleeping hours, seeing that I am having troubles withthe generator, will the propane heater run off these house batteries? for how long? Thanks a bunch.


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I'm not sure if there is a way to load pics. fo that they display without the viewer having to load them, but to maybe save you the time, the pic is of my Cole-Hersay 4? position switch,
both.      these are the positions.
is this for using & charging?  This is really my question. the positions are obvious (I guess)
It appears to be a typical marine battery switch. If you do have an operating inverter, you should be charging the batteries when on shore power and with the generator running. Use a VOM (Volt-Ohm-Meter) and see if the battery voltage is above 13.2 volts with the switch on both and plugged into shore power. If above 13.2v, your batteries are being charged. Take a reading on both batteries.
The marine switch is used to select between two battery's or shut both off. The switch is designed to transfer the load from battery to battery under load. If you only have one battery select the switch position that the lead is connected to. I label the battery's  1 or 2 so I can keep straight which I am using. Running the heater will use some battery so during the time you use the heater put the switch to both(if you have two battery's)
I can't tell what year/make/model of truck + camper you have from the tiny avatar picture, so it is impossible to answer your questions with any accuracy. Different RVs use different electrical designs and yours is probably a custom design anyway. You need to provide more details about this rig, or at least a picture we can see well enough to make out some details. It appears to be some sort of camper shell mounted on a flatbed truck, but where is the generator and how does the camper portion get power from the truck?

1 should these batteries charge when plugged in to "shore" power?
Typically, yes. There should be a 12v converter & charger that does this.

2 does switch position matter    "        "                        "          "        ?
Yes - others have already explains that the switch determines which battery(s) are connected to the power system.

3 does the truck motor provide  "house" charging?
Typically, yes, but it depends on how the camper portion is tied to the truck power system.

4 should the (onboard diesel) generator charge them?
Again, typically yes. In most systems the generator merely substitutes for 120v shore power and everything else works the same. However, I've seen a few where the generator had its own DC output and that was used to charge batteries and provide 12v to the house.

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