New (to me) rig with potential electrical "issues"

mikracer · 10-07-2013, 07:57 PM

Hey guys,

I just purchased a new to me SMB over the weekend (just posted an intro in another thread) and finally got to spend some time looking over it in detail after work. I wanted to check the house batteries since the PO said there were two under the gaucho. Been reading up on adding solar and installing new AGM batteries. Well I pulled up the gaucho bed and saw kind of a cluster f#$% of wires.

So where to start... There are quite a few wires down there and it makes me wonder if it came like this from the factory. There are a few that aren't even connected to anything but I don't know where they lead to since they get back behind the paneling. I've taken some pics so you can see what they look like. Also, after trying to see if maybe something isn't connected, I tried flipping the breaker switches and to my surprise, flipping them on and off does nothing. In either position, I can turn on the fridge and small fan mounted above the sink. Not sure where to even start tackling something like this and I'm hoping I can get some insight from everyone on here. And to top everything off, the batteries are mismatched.

86Scotty · 10-07-2013, 08:10 PM

That is absolutely NOT how it came from the factory. SMB wiring is usually very clean from the factory. It should look a little more like this:

What you are holding in the 2nd pic is an unused power wire and ground, or it should be. That's exactly what they look like in mine. It should be running to a power plug (cigarette lighter/charger type plug) or a DC appliance, such as water pump, furnace, etc. Is everything working? Do you have a phone charger you can plug in to all of the power ports to see if one is not wired?

I'm also wondering if the PO just had an inverter or something under there before that had several wires running to it. The silver box on the left is a power converter, not inverter. It takes AC power and charges your DC (house) batteries when you are plugged in to shore power.

Ford_6L_E350 · 10-07-2013, 08:15 PM

Troubleshooting wiring from a photo is not something I'd like to do. In person, ok, but not from a photo - or several photos. Having said that, the two big wires with caps on them look like AC power lines, although they may be from a no longer used DC circuit.

But, I can tell you that the breakers generally only affect the AC power coming from outside the van (shore power) and generally all the appliances, etc. work off DC power (the house batteries). So, breakers on or off has no effect on the appliances running on DC power.

Mike

mikracer · 10-07-2013, 08:36 PM

Thanks for your replies! I just tested an outlet near the sink (the only standard outlet I can see) and it doesnt work. I imagine those two capped wires are for that outlet. I think I'm getting confused on the different power sources. I didn't see an inverter under the gaucho or anywhere else, so how would a standard outlet work off of 12v power?

Do the appliances automatically switch over to shore power if I'm plugged in? If thats the case, I should be able to plug in and test the breaker panel, right?

larrie · 10-07-2013, 09:55 PM

If the outlet by the sink is a standard one like your house you should be plugged into shore power to test it.

To really figure out the wiring you will need a multi meter. The meter will read both AC and DC as well as amps and continuity. Once you have the meter you can easily tell which wires have voltage on them and track them back to your fuse/breaker panel.

mikracer · 10-07-2013, 10:07 PM

Quote:

Originally Posted by larrie

If the outlet by the sink is a standard one like your house you should be plugged into shore power to test it.

To really figure out the wiring you will need a multi meter. The meter will read both AC and DC as well as amps and continuity. Once you have the meter you can easily tell which wires have voltage on them and track them back to your fuse/breaker panel.

Ok, that makes sense. I'll plug it in tomorrow to see if the breaker switches and the house plug works. Is there a proper procedure of plugging in the shore power?

**daveb** · 10-08-2013, 01:13 AM

I certainly hope you're somewhat familiar dealing with AC. Just something like AC polarity is not known by some and it is possible, what's the saying...death or serious injury may occur. If you get the polarity backwards, the vans chassis can become energized and if you lay against it you might be thinking of that saying. At least wear a pair of leather gloves.

Some inverters or converters might trip a GFI power outlet but in most cases won't and is a safer plan. Usually SMB's are wired for 120v not 240 unless the owner specifically wanted it for some reason. Hopefully he supplied you with a 30A shore power cord. If not you'll need one or in some cases purchase an adaptor. If your using an adaptor do not run something that pulls high amps like a microwave or heater if using a light extension cord. I used a adaptor and industrial cord to feed my inverter for charging.

Take care.

yvrr · 10-08-2013, 07:51 AM

Unless you are really knowledgeable about wiring, I'd suggest setting up a visit to SMB in Fresno. They could figure out the wiring issues, install new batteries, and add solar if desired.

mikracer · 10-08-2013, 09:28 AM

I do have the adaptor for the shore power plug in (one side plugs into van and the other side has a female "standard" plug). Once I plug in to shore power, does it override the 12v system automatically or do I have to flip a switch somewhere? Just wondering how I would be able to tell since everything works right now off of the house batteries. Sorry for such the newb questions...

Ford_6L_E350 · 10-08-2013, 10:17 AM

If the breakers are OFF, when you plug into shore power, nothing much happens. Power goes to the breakers and stops. Turning on the breakers should put AC power to a converter/battery charger and to the AC outlets. Then the DC appliances continue to run on DC, but the DC is supplied by the converter.

Mike