Power sources

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gmatt2

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Sep 16, 2024
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Location
Bedford, IN
Finally got the TT home and starting to rehab. I already know I've got some wiring to trace and work on (for example I'm replacing all the lighting.)
As a rule, are certain things powered by the battery and pigtail vs those powered by the 30 amp service?
 

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Lighting, furnace, control circuitry for water heater and (RV type only) fridge, are 12V DC operation and run off of the battery. Plugging into shore power ("30 amp service") brings 120V AC (house style) into the rig which would run a fridge (on electric), a microwave, TV, outlets, etc. along with a converter, which changes 120V AC to 12V DC and charges batteries, along with running your DC stuff while plugged in.

So be careful that you don't confuse stuff in the DC system with stuff in the AC system.
 
2 separate circuits of wiring. 120 volt AC and 12 volt DC

The right side with the automobile type fuses is the 12 volt DC system side. (house batteries, converter charger).

The left side with breakers similar to the ones in a home is the 120 volt AC side.

The only crossover of the 2 separate circuits of wiring is the converter charger. The converter charger needs 120 volts AC that it uses to convert to 12 volt DC power. The converter charger powers all the 12 volt DC needs of the house and charges the batteries.
 
YES../ Shore power (30 or 50amp)
Powers the converter (Converts 120VAC to battery power_
Air Contitioners.
Microwaves.
The ELECTRIC element in the water heater (if any) and Absorption Cooling Unit (Fridge) IF any
Residential Fridge (If so equipped) All outletls.
Televisión and radio may or may not be shore power or battery power. (Automotive like radio is 12 volt.)


12volt (Battery) powers all lights.. Fans (Vent fans) Furnace.. Control power for Fridge, water heater, air conditioning (optional) Water pump and Furnace.. If you have slide outs.. or electric steps or jacks. add those to the battery list. If you have a macerator toilet.. Battery powered.

IF and only IF you have an inverter.. then SOME 120 volt stuff may also eat 12 volt power..

I think I've covered it all.. but there is often a "Something else" (Power awning 12 volt)
 
there has to be something charging the batteries and it is almost certainly a converter.

What make and model is the rv? Someone here can probably tell you exactly where to look with that info
 
Is there a way to find out if I have a converter that charges my battery?
It would be unusual, or was removed if it didn't have one.

1730643189932.png

Odds are it's a Magnatek and you'll find it by tracing the fat red wires at the top of the fuse board. Odds are it's right behind the fuse board. If this is the original Magnatek converter you're in for a modern replacement.

Mark B.
Albuquerque, NM
 
If you look at the panel that you posted a picture of in your first post it is identified as a Magnatec Model 80 so read over this installation and operation instruction sheet. It does have a built in converter so there should be one located behind it. I am sure that there was one when the RV left the factory and it would be unusual if it isn't still there. I would look something similar to this.
1730647233864.png
If you trace the largest red wires from the back of the panel in the second picture, it should lead to both the converter and to the battery.
 
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Excellent responses above.

If it does not work when no shore power, it runs on 120V.
Battery is also REQUIRED to tow. it supplies brake power in case of a break away situation.
 
Show us a better pic of the area behind the power panel. I see a bunch of white wires (grounds for 12v) probably connected to a ground bar, possibly on a bracket screwed to the floor. Follow the the two red wires that come out the back of the panel. One goes to the battery, the other goes to the power converter.

Charles
 
So, in addition to all the good responses I got, I did a little research with a multimeter and found out I do indeed have a converter. I also managed to determine what the 120v breakers supply.
As far as electrical, I still have a few 12v fuses to trace and see what they feed.IMG_20241026_125255595_HDR~2.jpg
I've already found fuses 2,3,5,6
#7 says it's the furnace but I found one of the 120v breakers went to the furnace.
 
Kirk is correct, the MagneTek 80 is essentially the upper half of a MagneTek/Parallax 6300/7300/8300 series without the converter built into the bottom half. Thus the stand alone deck mount converter, which can be easily replaced with a multitude of other units, one of the best being the Progressive Dynamics 9200 series.

And as noted by Gary and Kirk, the furnace should not have 120v AC going to it, unless someone has added something (probably undesirable) You are probably finding a Romex® cable that just happens to be passing underneath the furnace that looks like it is going into it.

Charles
 
And as noted by Gary and Kirk, the furnace should not have 120v AC going to it, unless someone has added something (probably undesirable) You are probably finding a Romex® cable that just happens to be passing underneath the furnace that looks like it is going into it.
Actually there's a slight chance the furnace runs on 120 VAC. Suburban makes a 120 volt version of their gas RV furnace for park models. FEMA used them in their hurricane trailers a few years back.

Park Model (P-40) for RVs & Campers - Suburban
 
With the shore power disconnected, I tested the wires and nothing. I checked again after plugging in the shore power and my tester alerted on the some of the wires.
The line tester I'm using is rated 120v - 600v. It doesn't alert on 12v. I'll add a photo tomorrow.
 
The vast majority of the wires shown indicate 120v. Does the 2nd picture mean this could be both?
 

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According to this Atwood Installation Manual, there was a 120v AC model.

One or the other, but not both. Look at the bottom most wiring diagram on p.5 of the manual linked above.

Have you found a data plate on the furnace with the exact model number?

Useless if you are going to be traveling unless you are totally staying in campgrounds with power, but as Gary noted, if this were installed in a Park model (semi permanent), then it would be useful.

Charles
 
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