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plossl · 12-01-2009, 12:50 PM

I'm replacing the Univolt with a WFCO converter. The main breaker attaches to the converter box on a blade and seems to have only one set screw to attach the AC power wire and the black wire from the converter. Do they both attach to the same screw? Doesn't this take the breaker out of the loop?

Minno · 12-01-2009, 12:52 PM

Got a picture? That'll help a lot.

Aerowood · 12-01-2009, 01:11 PM

If I read this correctly and I'm not sure that I am, but the blade that the breaker slides over should be powered by the shore power cord inside the breaker box. That slide is called the positive bus bar and the shore power cord black wire should be attached to it. There should also be a neutral bus that the shore power white wire is attached to. last but not least is the ground bus that will have either a green wire or bare copper wire attached to it. Do not jumper the nuetral to ground.
The breaker should have a terminal that the black wire from the circut for the converter attaches to. This puts the breaker in between the positive or hot bus bar and the circut to be used

plossl · 12-01-2009, 01:44 PM

Thanks for the help. That makes sense: the power wire from shore power attaches to the positive bus bar. I'll try to find the attachment point. It might come in from the back.

HowieE · 12-01-2009, 02:56 PM

If you have not yet hooked the converter up consider returning it an buying a better quality converter. The WFCO converters tend to fail in short order. I have repalced one in my daughters trailer and that one has now failed. A 4 year old trailer.

Consider a Progressive with a battery monitor so you don't cook your battery.

Minno · 12-01-2009, 06:55 PM

Quote:

Originally Posted by plossl

Thanks for the help. That makes sense: the power wire from shore power attaches to the positive bus bar. I'll try to find the attachment point. It might come in from the back.

Plossi,

Please post a picture of what the heck you’re looking at! If you’re looking at the main a/c panel, then the shore power cable should feed into the inside of the panel through a clamp of some sort. Once inside the panel, the outer jacket of the shore power cable will be removed, and then the green wire is attached to the ground bus bar, the white wire attached to the neutral bus bar, and the black wire should be attached to one end of the main breaker. The other end of the main breaker should be connected to the power bus bar where other circuit breakers will be attached. Each additional circuit breaker gets its power from the power bus bar, and supplies 110 VAC to the black wire that attaches to the screw on the breaker. That black wire then combines with another white wire and ground wire to become a standard 110 VAC wire commonly called romex, and designated by its size and load carrying capacity. 12-2 (one black, one white, and one bare for ground) can handle up to 20 amps, while 14-2 can handle up to 15 amps. The main circuit breaker should be 30 amps, and the other (feeder) breakers will be either 15 or 20 amp, depending on the load requirements and romex wire gauge used.

I’m concerned that you’re looking for a wire from the shore power cable directly attached to the power bus bar – the thing you referred to as the positive bus bar. There should never be any wire directly attached to the 110 VAC power bus bar – everything must run through a circuit breaker. Either the main to feed 100 VAC to the bus bar, or the feeder breakers to supply 110 VAC to the various circuits.

Most converters (that I know of anyway) plug into a standard 110 VAC outlet, and are not directly wired into the main electric panel. But, I’m not 100% sure exactly what you’re looking at.

Forgive me if I’m way off base here – but I think you’re on your way to making a fatal mistake. Or at least a shocking one. No pun intended.

A very concerned fellow airstreamer,
Chris

plossl · 12-02-2009, 04:29 AM

minno-
I have a long work day today so the earliest I can post a picture is tomorrow, but I think I have it figured out. The power coming into the trailer goes to a 30A breaker then to the bus bar. Trailer power comes from a second breaker attached to that bus bar. I wasn't grasping the that I needed more than one breaker. I'll show you a picture in a post tomorrow.
WFCO was the one to get when I bought this six months ago. . .are they turning out to be a bad choice?

Minno · 12-02-2009, 06:33 AM

Quote:

Originally Posted by plossl

The power coming into the trailer goes to a 30A breaker then to the bus bar. Trailer power comes from a second breaker attached to that bus bar. I wasn't grasping the that I needed more than one breaker.

Hey Plossi - yes, that sounds much, much better. I think you have a better grasp of the breaker box now. Post pics, and ask questions. Lots of questions are very ok here!

There are a ton of knowledgeable people here that can help you figure out pretty much anything.

I have no experience with the WFCO converter. Maybe someone else can give you another opinion on that.

For what it’s worth, when I buy a new converter for Little Girl, it’ll be a converter with a smart charger (aka – progressive charger, 2 or 3 stage charger, charger wizard) to keep the batteries from being over charged.

Chris

Aerowood · 12-02-2009, 07:00 AM

Minno you are absolutely correct, the shore power wire to the main breaker which is attached to the main bus bar. My mistake for omitting that crucial detail

Kip

plossl · 12-03-2009, 08:11 AM

Here is what I think is the correct solution to my breaker question. The shore power comes into the WFCO converter via the gray wire. This is screwed to a 30 main breaker, which attaches to the bus bar. The WFCO converter takes this power from the bus bar via a black wire to ANOTHER breaker on the bus bar. I wasn't understanding from the converter instructions that there were two breakers--I thought that the bus bar was directly wired to shore power and I couldn't find a way to do this. What do you think? As long as my polarity is right I should be able to avoid singed eyebrows, shouldn't I?

The second picture is my mystery wire. These two holes in the wall are in the back of the trailer near where the univolt sat. The hole on the right has all of the 12V circuits and 2 larger white wires. One of the white wires screws into the aluminum frame of the wall. The other, I think, was attached to the univolt somewhere. Where do I attach it? Is it a ground? A negative? Any thoughts?