Wire Nuts, Parallel Batteries and other thoughts

[48Rob]

Brian,

I'm not disputing that, in general, in a situation where vibration can cause work hardening or connection failures in electric systems, stranded wire is a better choice than say, Romex, because it is.

The point I was making is that there are a lot of people who take what they hear on a board like this as gospel, and while educating people is an important thing, becoming too technical over issues that will NEVER affect the average reader serves no purpose.

Such as stating (in effect) that Romex is destined to fail because of vibration in a teardrop.

Could it fail? Sure, anything "could" fail.

Will it fail? The chances of a failure "because" someone used Romex instead of stranded wire are so remote that there is really no purpose served by fussing over it.

I appreciate your technical knowledge very much, you've answered several questions I've posted.
I'm sure many, many others here also have benefited from your experience.

That we can share what we know is good, that we can get too immersed in the details only serves to confuse those who need practical, not technical answers and information

Rob

[bobhenry]

So why not just avoid the potential for problems completely by using stranded copper rather then Romex?

Wire Nuts. The don't work with anything but solid-core, so see item 1. Crimp connectors are easy and secure, and if you have any question about exposure to the elements it is easy to cover them with heat-shrink tubing.

I didn't say it see above !!!!

I used stranded wire from a 12 gauge extension cord. I used forked terminal ends mounted solidly onto the screw terminals of the duplex outlets. Never liked the stab in and hope it connects in the backs of the duplexs and switches.

HOWEVER many of the grouping connections are made with wire nuts With only 1 problem. Had 12 ground wires in one connection and wire nut was way to small. Went to a grounding bar out of a fuse box and no further problems.

[48Rob]

Vroom,

This is good!
This is the kind of info that the average td builder shoud be able to easily access!

The most likely failure mode with Romex and regular house electrical outlets would be a poor connection from the typical method of inserting wire into outlets. The design of 'stick it in' connections was never intended to handle potential movement of the wires.

And this;

there are other types of wire out there which are much more suitable to TD usage than Romex. They are not hard to find nor much more expensive.

When the average td builder goes to the big box store to buy "wire" for their trailer, they ask for help.
The guy, or gal asks what they need?
"Wire and outlets for my trailer" they reply.
The store employee asks; 110 Volts?
Yes, they reply.
"Here is the wire you need, the employee says in an authorative tone!
"And you'll like these "special" outlets, all you have to do is shove the wire in the back, no special bending, no special tools".
Great! says the td owner, as they pay for their supplies and head home.

The average store employee hasn't a clue about which wire, or outlet type is best for a td builder.
Wire is wire...and easy to use outlets must be good, cause we sell 'em!

If we make them aware here, before they hit the store, they'll be much more able to justify an extra dollar per outlet for a part that they understand will make their build safer.

But when we say things like this;

But hook up an electric heater and that may change... remember that heating in a circuit is proportional to the *square* of the current multiplied by the resistance. So a 1500W heater pulling 12.5A with a 1ohm resistance in a connection generates over 150W of heating. That is enough to cause some issues

(Translation) loose connections in your electrical system, when placed under heavy load (such as when an electric heater is turned on) can cause enough heat to start a fire!

Lest anyone think that a superior attitude is going on here, I assure you it is not.

We each have our own specialties, our own areas of expertise.

The point is that if I'm having a heart attack, I appreciate my doctor explaining to me in easy to understand terms (not medical dictionary)what my options are, and why.

The same as considering that people who are here looking for advice on their electrical system probably aren't experts in the field, and would appreciate brief, easy to understand options to consider.

Thanks for hearing me out!

Rob

[Miriam C.]

If you think you will have a vibration issue then by all means use stranded. Only you know how and where you will be towing. I take mine down some pretty washboard roads and it even survived I-20 out of Shreveport LA Although I wasn't sure for a while there.

The stranded seems to be easier for some to bend. I had stacks of romex and used it. My receptacles are a combination stab in/side screw, I used the stab in. The expensive ones not the cheap ones. If you have never tried to pull one of these out---I could send you one---a pretty red one. My wire is in a plastic wiremold chase. It really isn't going to go anywhere. If you properly install your wire the type isn't going to cause a problem.

I have a heater, air conditioner, hot plate and even a hairdryer. If you look at some of our builds you will see folks careful to bury the wire so the connected joints don't vibrate.

The thing is if you use a solid on a large vibrating machine you might get some fracturing someday. You don't want that in a factory or a machine.

[rmclarke]

About the worst vibration you'll get in a td is a young couple who left the kids with grandma for the weekend...

that just reminds me.........




ooh.....never mind

[vrooom3440]

So why not just avoid the potential for problems completely by using stranded copper rather then Romex?

Wire Nuts. The don't work with anything but solid-core, so see item 1. Crimp connectors are easy and secure, and if you have any question about exposure to the elements it is easy to cover them with heat-shrink tubing.

I didn't say it see above !!!!

I used stranded wire from a 12 gauge extension cord. I used forked terminal ends mounted solidly onto the screw terminals of the duplex outlets. Never liked the stab in and hope it connects in the backs of the duplexs and switches.

HOWEVER many of the grouping connections are made with wire nuts With only 1 problem. Had 12 ground wires in one connection and wire nut was way to small. Went to a grounding bar out of a fuse box and no further problems.

You did much as I am suggesting. And I like your approach of using crimp connectors under the outlet screws a LOT

I am unsure why a wire nut would not work on stranded wire, at least the most common types. The very fine strands may bend too easily I suppose. I think my favorite approach here though would be to solder the connection and use the wire nut as insulation

Rob, we are pretty much singing the same tune albeit in a different key. When I include complete thoughts... I err towards the side of too much tech to back up what may otherwise be just an opinion. It can be too much for some to understand though. I do know that the first time I went through the math I was amazed at the magnitude of the heating affects I have pulled crimped on 12v ground connectors where the insulator was melted from resistive (bad connection) heating. The wire was fine, further supporting the thesis of a bad connection causing the problem.

[48Rob]

Vroom,

Good discussion!

Being technical to back up a statement is sometimes a good thing.
As has been pointed out in other discussions, too many "opinions" are handed out as fact in an arena where the readers are looking for/expecting factual information to help them make a decision.

I won't get into what people believe/or shouldn't on discussion boards...thats a whole separate debate
But the point is, self regulation is really important for a good board.

Sometimes I just have a bad day...perhaps yesterday was one of them...
When I'm browsing, and come across a statement that is presented as fact, yet comes across as more of an emotional rant, with no info to back it up, I get a little frustrated.
Sometimes I maybe see things that aren't there, but discussing them usually clears things up.

Yes, I think we are on the same page. Thank you for taking this all in and not getting upset to the point the whole thread goes down the drain...or up in smoke as it were...

So, back to the subject;

Wire nuts on stranded wire...
I've used them for years, as have many others in non vibration applications, and had no issues.
Same for crimped connectors.

Human error, generally can be used to explain the failure of crimped or wire nutted connections gone bad.
Then again, human error accounts for pretty much all failures...

This points back to the push in outlets.
Miriam has one that the wire was obviously installed correctly in.
I have also had to, on a few occassions, cut the wire from the back of these outlets because even after depressing the catch, it would not come out.
However, more often I encounter them because they need to be replaced after a customer calls to report that "smoke was coming from the outlet".
It is quickly revealed that the wire was loose, and (the connection) would not have failed if it had been correctly inserted, or better yet, screwed down.

I'd suspect the majority of the 12 volt crimped connections you've replaced were due to improper installation by someone that was not experienced enough to know that the way they were doing the job was not the right way?

Rob

[brian_bp]

I'll put in another vote for crimped-on ring terminals, as a sound way to connected stranded wire to conventional AC devices such as switches and outlets. Sounds like a great idea to me.


Of course, it's important to do the crimped connection well.

I'm not personally comfortable with ordinary wire nuts (not the ones with set screws in them) on many strands of wire... they just don't hold very well, at least in my limited experience with them in this type of use. The vent hood with fan and light over the stove in my trailer was wired with these, and although it generally worked for many years the connections just fell apart when touched (when I had to fix the fan motor). The hastily crimped connections on stranded wire in the rest of the interior wiring are still solid, at almost 30 years old. I would rather do the crimps, although Posi-Lock connectors are a nice option which don't require a crimping tool and can be disassembled.

[Russ in California]

(Artie Shaw as the german soldier on Laugh-in) "Veery interesting".

Ok....now, I'm just sayin'...at the county garage where I work, in the heavy equiptment shop, they ONLY solder their wire connections. Not sure if you'll get much more vibration with a semi-truck or construction equipment.
As for corrosion, again...I'm just sayin', we're RIGHT on the coast and it's been said before: "rust never sleeps". They still use the solder.
This has been successful here and is standard procedure.
Since my design is of the "Outback" TD ilk, I believe I'm going with solder and heat shrink though most of my lights will probably be LED battery op with maybe a fan and of course the trailer lights.
Seems many have used other methods with success. Awesome.
Could just come down to 'situational conditions'.
Like I said...I"m just sayin'.

[wlooper89]

I believe that solder gives a superior connection. It protects from corrosion of the copper wire and of the connection shaking loose from vibration. When possible I crimp and then solder. This works very well with ring connectors.

Solder will not withstand the heat of a short circuit, but I figure that is what fuses and circuit breakers are designed to handle. I would rather know the connection is unlikely to shake apart or be pulled apart over time.

Regards, Bill

[Lgboro]

Is a wire suitable for teardrop use if it has the following printed on the sheath "14 awg MTW or THHH or THWN (UL) or AWM or gasoline & oil resistant II 600 volt VW-1" ? I understand that some circuits will require a heavier wire if for air conditioner or higher volts or amps are needed. If this wire is ok is it suitable for both AC and DC?

Edit...it is a stranded copper wire that I have free access to in a quantity necessary to complete all my light and fan wiring.

[Miriam C.]

Yes! The gage of wire used is determined by the amps pulled. By code it should be in conduit because it doesn't have that outer protection that house wire has. The plastic wiremold type is fine for that. My personal bias is for grounded so a white for neutral, black for hot and green for the ground You don't have to color code them that way but make a permanent chart for what color you use and fix it to the wall near your box.

14 gage will pull a very small air conditioner. I would go bigger just cause I am gonna get hit for not saying it.

[brian_bp]

Examples of wire gauges versus current:
In household wiring, I believe that 14 gauge is used for circuits carrying up to 15 amps, with 12 gauge used for up to 20 amps.

[Alphacarina]

The gauge of the wire is determined by the amp draw and the length of the wire - You'll find some pretty large draw appliances which don't use a 12 gauge pigtail and they can do that because it's not very long - A 12,000 btu AC which needs a 20 amp outlet probably only has a 14 gauge cord . . . . . but not a very long one. As small as a teardrop is, you probably don't have a 120 volt wire anywhere in there longer than 10 or 15 feet and you could safely run just about anything on a 14 gauge wire . . . . .so long as it wasn't very long

I'm another one who wouldn't use any solid core wire in anything that vibrates as much as a motor vehicle . . . . or a trailer - Don't think you'll find any of it in your car either

There are federal regulations which prohibit it in boats and planes largely because it's use can injure or kill unsuspecting passengers, so basic negligence laws would apply - Everyone knows it can crack and fail due to vibration

What you use in your own teardrop build is entirely up to you and hopefully only you will be affected by the choice . . . . unless you sell it to someone else later on down the road. There are no laws for trailers that I know of . . . . just as there were no laws about the amount of flormaldehyde trailer walls could outgas . . . . . at least until Katrina

The fact that you won't find any solid core wire in cars (there's probably a law which prohibits it) or planes or boats is good enough for me - You can tempt fate in your own vehicles if you like but common sense should be 'speaking' to you I think
Worst case would be that you do it because you don't know any better and that's why we have threads like these

BTW - I had 4 L-16 six volt batteries on my 34' sailboat arranged in 2 separate banks (nothing in parallel) and even with my 12 volt electric refrigeration I could anchor for about 10 days before needing a recharge . . . . . assuming some sunny days so that my 2 solar panels could help out some

Don

[Miriam C.]

Amazing how many folks "know" better around here. Those of you who can't show proof might want to keep your statements as the "opinions" they are, mine included.

Those of you who are buying wire get what is easiest for you to work or pull depending on where you are putting it. Mine is totally in the galley and replaceable if there is ever a problem. The stranded is easier to work with and unless you are using the more expensive stab in receptacles, stranded is so much easier to wrap around screws. I think that is the only real reason to use it over something else.

Now look for a separate post for a new debate.