Why does the converter/refrigerator have a plug?

[fusedlight]

In all discussions I've been seeing, the ones on brakes and this one, the color coding seems so at odds with what I've learned over the years:

With DC: Red is Positive and Black is Negative
With AC: White is Neutral and Black in Hot
With 3-Wire AC: White is Neutral, Black is Hot, and Red is Runner.

Brown wires?? In my book, the only place brown insulation should show up is in wiring audio circuits. Of course, I learned this from my Dad... and old-school EE who worked at Bell Labs for nearly 50 years. He'd poke me with a sharp stick if I screwed up the colors. And speaking of screws... if those slots on a screw didn't line up on the face plate I was in Big Trouble.

[pindraak]

Originally Posted by P. Raz

I was thinking of the screw clamp on a breaker. I suppose you could tin it?

I think the stranded wire makes a better connection on a screw clamp - breakers and grounding bars, provided it is not way smaller than the hole/channel. The hard wire only makes one line-like connection on either side of the hard wire, whereas the stranded squishes and contacts all over the place. There could be an issue that the stranded is more likely to pull loose, but nobody is going to be pulling on these wires, and you can test security by pulling after install. The one wire I am concerned about is the shore cord, so I am going to clamp it down soundly outside the box.

[pindraak]

Originally Posted by fusedlight

In all discussions I've been seeing, the ones on brakes and this one, the color coding seems so at odds with what I've learned over the years:

With DC: Red is Positive and Black is Negative
With AC: White is Neutral and Black in Hot
With 3-Wire AC: White is Neutral, Black is Hot, and Red is Runner.

Brown wires?? In my book, the only place brown insulation should show up is in wiring audio circuits. Of course, I learned this from my Dad... and old-school EE who worked at Bell Labs for nearly 50 years. He'd poke me with a sharp stick if I screwed up the colors. And speaking of screws... if those slots on a screw didn't line up on the face plate I was in Big Trouble.

My understanding was that with DC, white and red are positive standards and black is ground. I talked to a the tech from the place where I bought my converter and panel yesterday, though, and he said there really is no standard, and you should never assume anything. To me, the smart thing would be to harmonize them all, which would only require creating a DC standard with black for hot and green for ground.

[Raz]

It's your trailer. You certainly can do what ever you wish. I hope it works out. Raz

[Frederick L. Simson]

Originally Posted by fusedlight

With DC: Red is Positive and Black is Negative
With AC: White is Neutral and Black in Hot
With 3-Wire AC: White is Neutral, Black is Hot, and Red is Runner.

Brown wires?? In my book, the only place brown insulation should show up is in wiring audio circuits.

In this global economy I am seeing a lot of AC wiring with Brown as "Hot" and Blue as "Neutral" with Green/Yellow stripes as "Ground" in equipment manufactured in Asia. A technician friend gave me a poem to help me remember which wires are Hot:

Black and Brown
will put you in the Ground

[fusedlight]

*sigh* What was it that President guy said?? Oh yeh... "Trust but Verify". I kind of figure with a multimeter and a signal tracer I'll be OK. Just as long as I don't have to mess with anything as nasty as the Lucas wiring that was on an old '72 Land Rover that my ex had!

[mszabo]

A lesson well learn. Never assume anything when it comes to the wiring in these trailers.
One mans cobble is anothers pain in the #%^.
The lesson here is #1 what caused the wires to melt in the first place.
#2 see #1.
First thing, disconnect shore power and batteries, trace all wiring from source to panel or
power supply. Never assume anything, wire colors and or type and size mean nothing.

Something not all people know, the big box store employees usually don' t give advise on electricial installations due to the liabily. (well you told me) after there house burnt down.
Although they have tried to hire retired electricians to assist customers. Seek that person out.
The best thing one could do is buy the basic book on electrical. This will give you the tools to better understand how ac / dc work.

To answer the question, why a plug. A plug makes sure the polarity is maintained, hench
Your plug has two different sizes and a ground.

Glad you found the problem and no further damage was done.

[sparky1]

White should NEVER be HOT in any way. in a DC circuit.

Black or Red should be From A positive source.(hot) in a DC circuit.
........................................;.
AC circuits are totally Different, consult (National Electrical code).
But it's your trailer, hope you don't destroy it or Hurt your self, RV repair Techs are NOT Certified Electricians.

[Byron Kinnaman]

Originally Posted by sparky1

White should NEVER be HOT in any way. in a DC circuit.

Black or Red should be From A positive source.(hot) in a DC circuit.
........................................;.
AC circuits are totally Different, consult (National Electrical code).
But it's your trailer, hope you don't destroy it or Hurt your self, RV repair Techs are NOT Certified Electricians.

Sparky,
I'm not sure you meant what you said. In DC circuits the standard convention is black, negative and red, positive, all other colors are also positive.
In house wiring white neutral, all other colors hot.
Travel trailer wiring seems have gone closer to house wiring with white being negative, and all other colors positive and the positive bus being black.

Since the wiring colors are mixed up in trailer wiring as standard DC electronics wiring it would be a good idea to always verify with a Digital MultiMeter (DMM).

Byron
EE Retired

[sparky1]

White should (Never) Have a Positive potential (HOT) it should be used as a Negative or Nutral.

Red or Black Should Be Used as (HOT) Positive potential

[Thomas G.]

Originally Posted by Dan Meyer

Good theory, but maybe wrong. In my 2000 Scamp, almost all AC power cables are solid conductor romex wiring.

-- Dan Meyer

Hmmm, I'm surprised to hear that. I don't like working with stiff wires, so I'll keep on using braided wires.




.

[sparky1]

from your Power Panel to all Receptacles should be Romex...

!2 volt circuitry totally different
Recrecational Units are covered by National Electrical code starting with article 550.
I will not argue with what it states--do as you please---12 volts DC will not kill you---but 28 volts @ 1/10 of a amp can.under certain instances.

[Byron Kinnaman]

Originally Posted by sparky1

White should (Never) Have a Positive potential (HOT) it should be used as a Negative or Nutral.

Red or Black Should Be Used as (HOT) Positive potential

Here's 3 Bench Top Power Supplies. Look carefully at the color of the connectors and the markings. I can supply a lot more documentation if you.
Sometimes Black is negative... Sometimes Black is hot or positive.

Now go out and lift the hood on your automobile. Look at the cable colors coming off the battery. Now determine which one is positive and which one is negative. Isn't a battery in your automobile DC?

[Dan Meyer]

Originally Posted by Byron Kinnaman

Here's 3 Bench Top Power Supplies. Look carefully at the color of the connectors and the markings. I can supply a lot more documentation if you.
Sometimes Black is negative... Sometimes Black is hot or positive.

Now go out and lift the hood on your automobile. Look at the cable colors coming off the battery. Now determine which one is positive and which one is negative. Isn't a battery in your automobile DC?

You are absoluty correct. Red is positive, black is negative in the above mentioned equipment. But not on my Scamp. See http://scamp.n0kfb.org/manual/page15s.gif for the wiring diagram of my 2000 Scamp, as seen in the owners manual.

At work, the equipment I work on uses positive ground. In this equipment the negative leads are marked with either blue or black. The moral of the story: Don't assume anything unless you can live with possibly catastrophic consequences.


-- Dan Meyer

[Byron Kinnaman]

Originally Posted by Dan Meyer

You are absoluty correct. Red is positive, black is negative in the above mentioned equipment. But not on my Scamp. See http://scamp.n0kfb.org/manual/page15s.gif for the wiring diagram of my 2000 Scamp, as seen in the owners manual.

At work, the equipment I work on uses positive ground. In this equipment the negative leads are marked with either blue or black. The moral of the story: Don't assume anything unless you can live with possibly catastrophic consequences.


-- Dan Meyer

Thank You. That's my point. When wiring is involved always check instead of assuming.

[pindraak]

It sounds like white for positive is something of a trailer standard, I guess having to do with plug that goes to the vehicle. My trailer would be a real confusion to anyone assuming based on color at this point. I wired new outlets with red + and black -, the main leads are one white to the panel and one red to the converter, black for all major -. The main grounding wire to the frame is green. Two of the new light circuits are brown both ways: 14 ga lamp-type cord, and all the old stuff is white ground and who knows what color +.

[Byron Kinnaman]

Originally Posted by pindraak

It sounds like white for positive is something of a trailer standard, I guess having to do with plug that goes to the vehicle. My trailer would be a real confusion to anyone assuming based on color at this point. I wired new outlets with red + and black -, the main leads are one white to the panel and one red to the converter, black for all major -. The main grounding wire to the frame is green. Two of the new light circuits are brown both ways: 14 ga lamp-type cord, and all the old stuff is white ground and who knows what color +.

I believe it's the other way around. Trailer wiring is more like house wiring. White is negative and Black is positive. Hence the confusion.

[pindraak]

Originally Posted by Byron Kinnaman

I believe it's the other way around. Trailer wiring is more like house wiring. White is negative and Black is positive. Hence the confusion.

Yeah, I meant white for negative seems to be trailer standard. I think it is probably based on the 7 way trailer plug. I can't see how they came up with that though, since car batteries are always black negative, along with every car stereo I ever installed. If they were copying house wiring, seems like green would be negative. White is neutral and there is no DC neutral. The consistent thing would be to never use white with DC.

[ruscal]

One part of the NEC requires a service disconnect be provided at a piece of gear. The serviceman can then disconnect power before working on the gear. A plug would provide that disconnect, whereas the hard wiring would not. The code says something about the disconnect being within sight of the gear. Your breaker at the converter will likely be out of sight if the serviceman is working outside the trailer. It is not likely another person would enter the trailer and flip the breaker while the serviceman was working on the gear, but could happen. Usually new receptacles are trouble free until many plug/unplug cycles cause loose contact causing overheating. You should be fine with the plug and receptacle if newer.
Russ