Need help with reconnecting electrical

[Cristina1966]

Hi all,
Yesterday I removed a broken converter and was in the process of re-installing a new one when the there was a major short. I was pulled into the receptacle and was glued to it. I try pushing myself out and the other hand was also stuck. All I remember is that my 2 hands were glued to the trailer and I could not get them out with all my force. My body was shaking and I thought that was it for my life on earth. I was sitting on the ground and saw a piece of wood when I thought I could try pushing myself out. It worked! I disconnected myself from the short, disconnected the trailer from the power and haven't been near the trailer since. I am sharing this horror story so no one does the same thing I did. The stupid things I did: sit in wet ground when connecting electrical stuff, try to reconnect electrical system based on faulty memory instead of a voltmeter.
I am very afraid of finishing this job because I am not sure I understand what happened. Here is a detailed description. Please let me know if you can figure out what happened and the right way to do it.
There are 2 main lines in the left side of the trailer where the old converter was. I can't trace where they go because they go behind walls. One comes from the wall, is wrapped in black plastic, and has 3 solid copper wires inside: A black, a white and a green. The other line is made of stranded copper, it is thicker, and has a blue, a white and a red wire. This is very thick and does not bend easily. I have pictures attached.
I was connecting an outlet receptacle to the line wrapped in black to receive the new converter (which came with a plug). I connected the black wire to brass screw, white wire to silver screw and green wire to ground screw. To test if I had power in the outlet, I plugged the trailer in the grid. I heard a funny noise in the trailer but ignored and tried plugging an appliance to the outlet to see if I had power. This is when hell broke loose and I almost died.
Today, I went back and noticed that my husband had taped the blue and red wires of the very thick line together. I didn't touch this line when I was being shorted. Is this what shorted myself and the trailer? If so, how are these 2 lines connected? I thought the electrical sequence was: 110 power from the grid goes to to a line that splits into a 110 V system in the trailer and to the converter . From converter, a line goes to the 12V system (and battery if needed). If this is correct, what are these 2 lines I have on my trailer?
I plan on using the trailer as a guest house for my daughter so I don't need a battery. I still need a converter for the 12 V lights.
Thank you,
Cris

[mimiandrews]

ALWAYS unplug the trailer from 120v ac power when you are working on electrical wiring.

As you found out, AC can hurt you. 12v DC can't shock you, but it can set things on fire if accidentally shorted. Remove the negative terminal wire from the battery (or converter) when you work on that.

After the wiring is done, check your work visually (or better have a knowledgable someone else do it for you) and then plug things back in when your body is well away from the circuit. If your work fails this "smoke check" you will live to try again.

Sorry this happened to you.

[Cristina1966]

The trailer was unplugged when I worked on the outlet. I plugged it to test. Any help?

[TG Twinkie]

The shore power should be wired to a distribution panel located inside the coach. There should be a main breaker , plus 3 or so other breakers.
Did you disconnect the black (Romex) from something in order to wire it to the outlet?
I can't tell from your pics what the red, white and blue wires are. Can you tell us what they are connected to?
My guess. And it's only a guess. Is they are DC wires. Perhaps red= positive, white= negative and blue= charge line.
Where is the DC fuse panel located?
You said you removed the old converter. Where are the wires that came off of it ?
What appliance did you plug in that gave you the shock?
Post pics of the distribution and fuse panels if you can. The pic of the distribution panel should be with the cover off. Disconnect the shore power for now. We will see if we can help.
Have you had power connected to the coach previously?
What box were you touching that gave you the shock?


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[Wayward]

Originally Posted by Cristina1966

The trailer was unplugged when I worked on the outlet. I plugged it to test. Any help?

Well one thing at a time. Remember, the metal frame of you Airstream is connected to the AC ground, which is connected to the AC neutral back in your house. Since much of the Airstream is metal - your body can easily complete the circuit.

First, thank the angel looking over you.

Second, the most obvious place to start is that you did not have the receptacle tucked away in a box. If so, you may have touched a hot wire on the side of the open receptacle while trying to plug in your test plug. If so then cut the power, plug in the test load and reconnect the power. But you really need to put that receptacle in a box - even for testing.

If you did have it in a box and can say for sure your were not touching a bare wire on the receptacle, then you need to use the continuity setting on a volt/ohm meter to see if your hot wire black is connected to ground somewhere.

Another way to check if a hot wire is somehow touching the frame or other part of the trailer is one of these audible voltage testers. ....a must-have tool working with AC. I once found a nail puncturing an AC line by touching it to wall studs. It picks up the slightest AC field.



A safety tip I was taught a long time ago, when working near any exposed AC wire, keep one hand behind your back. The idea is to avoid a path for the current through the heart.

[idroba]

I would strongly advise you get someone more experienced with electrical systems to find the issues with your trailer and hook things up safely.

Although anyone can learn all about electrical systems, and understand them, and install them there are a lot of subtle little things which take a fair amount of experience to do correctly. The consequences of not doing them right can be catastrophic and even fatal, as you have found.

I honestly don't believe that anyone here can safely lead you through all the issues involved without actually being there and seeing what you are working with and doing.

[lewster]

"As you found out, AC can hurt you. 12v DC can't shock you, but it can set things on fire if accidentally shorted. Remove the negative terminal wire from the battery (or converter) when you work on that."

I BEG TO DIFFER!!! Obviously, you have never been 'bitten' by a DC jolt. It's the amperage that will kill you, but a DC shock can easily be just as lethal as an AC one. A DC shock is manifested differently in the body than an AC shock, but you get zapped just the same!!!!

And BTW, either AC or DC can and will start a fire under the proper circumstances...............

PS: I'm firmly with idroba. You need to get a licensed electrician to diagnose your problems and make the corrections needed. This is NOT a DIY project for the uninitiated......as you found out what can happen.

[Wayward]

Wiring an existing AC line to a receptacle in order to plug a converter in, is pretty darn simple and does not require a licensed electrician. Any handyman or educated owner can do it, including wiring the DC lines back into the new converter.

It does not sound like the OP necessarily has any wiring problems, just that the OP was not following basic safety rules and may have touched an exposed wire.

[TG Twinkie]

Just because an electrician is licensed. Doesn't mean he (she) knows what they are doing when it comes to wiring or troubleshooting an RV electrical system.
There are many threads here about how a "licensed" electrician wired up an RV to a 240 volt power source. Causing major damage.
If you don't have the experience to DIY. I would recommend a certified RV technician.
The systems in an RV are pretty basic. But as you found out. They can be dangerous or even lethal.
SAFETY FIRST.



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[lewster]

If the OP was shocked in the way he described and failed to follow basic electrical safety rules, then in my mind, he has disqualified himself from further electrical work on his trailer without potential lethal consequences!!!!! BUT it IS his trailer.....and he can do what he pleases.

He stated that he wanted to use the trailer NOT as an RV, but as a guest house arrangement for his daughter, so the services of a qualified electrician would indeed be warranted. Qualified RV techs can perform trailer wiring, but the home/trailer interface, while appearing simple, should be done with care to avoid 30 amp/240VAC mis-wiring and should NOT, IMPO, be left to an RV tech! Any RV tech has no business operating in a residential scenario, and any state, county or local building code inspector will come down on him HARD if he does.

Do I know how to install 30 amp outlets that are properly wired for RV use......SURE! Will I.........not on your life, as neither my certifications nor my insurance will cover any accident pertaining to said work. There have been numerous times when I find a bad 30 or 50 amp breaker at a power pedestal in an RV park, but I won't touch it (even though I am fully competent to do so) and have the RVer contact the office to have an electrician handle the job.

[TG Twinkie]

To be clear.
I was referring to an RV Tech doing the work on and in the coach. Not on the residential wiring needed to supply power to the coach.
At this point we don't know if the power source, the shore power cable or the panel/wiring in the coach is the source of the problem.
If for example one would use a faulty or incorrect extension cord to power the coach.
People have been known to remove the ground pin from an extension cord because it won't plug into the "old" 2 prong outlets. They may even use an adaptor to accomplish this.
All modern electrical outlets and plugs are designed so they can only be connected in one way. By defeating the design of the system, you are putting yourself and others at risk.
A two wire electrical supply to a trailer is a REAL safety hazard. No provision for earth ground and the ability to plug the cord in "backward" is very dangerous. Especially if the neutral in the coach is tied to the frame/skin.
The A/C power panel in the coach is considered a "sub panel" in which the neutral and ground are NOT "bonded".
If you don't have this basic understanding of the system. Then find someone who does.
YOUR LIFE AND THE LIFE OF OTHERS COULD DEPEND ON IT!!!


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[Cristina1966]

Thank you all. I am not planning on finishing this job on my own. I will be hiring an RV electrician. However, I still want to understand what happened because I like to learn. To answer some questions: The shore power is a 30 AMP new receptacle installed by a certified electrician. The 30 AMP power cord is in good condition. The 110 V and 12 V systems were working before I removed the old converter. There is one DC breaker on the left side of the trailer and one 12 V fuse panel on the right side. I can't tell which wires come from the breaker because the wires go behind the skin but I will try tweaking it tomorrow to see if they move. The appliance I was using to test was a power tool, which I never plugged because I was shocked before doing it. I will get some more pictures tomorrow.
Cheers and have a great Holiday break.

[mehes]

Cristina, good thing no permanent damage and hopefully a lesson you won't forget. It sounds like you were wiring correctly. One thing that has my interest is the funny noise you described when applying power to the trailer. Is it possible while moving the black wire around when wiring the outlet the insulation was cut? Perhaps where it passes thru a panel or under a clamp. You might want to do some continuity checks with your meter. I would start by checking continuity from each of the pins on the male end of your power cord to the the frame or skin of the trailer. Only the ground pin should have continuity to the trailer frame, anything else indicates a problem. Anyway take your time, think about what you did and what you touched when you got the shock and you might be able to figure out what happened. Let us know what you find out. And of course, don't plug it back in until it is fixed correctly.


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[mimiandrews]

I BEG TO DIFFER!!! Obviously, you have never been 'bitten' by a DC jolt. It's the amperage that will kill you, but a DC shock can easily be just as lethal as an AC one. A DC shock is manifested differently in the body than an AC shock, but you get zapped just the same!!!!

Sorry, I mis-spoke. 12v DC as wired in an Airstream, car, light airplane etc. usually can't generate that much amperage through the relatively high resistance of a human. Now, let some joker in a shop class hand you a charged capacitor, and the game is different.

All electricity should be treated with great respect and safety precautions observed.

[overlander64]

Greetings Christina!

Something occurred to me as I read your most recent post. Is it possible that your electrician may have wired your RV outlet as 220 Volt rather than 110 Volts? I know that this has happened to others, and it has almost happened to me twice in the past -- this is an installation uncommon to most electricians and the outlet does bear some resemblance to the more common range/dryer outlets.

Good luck with your project!

Kevin

[NavyCorpsman]

one tenth of an amp VAC WILL KILL YOU. I don't like the looks of the new work plastic boxes and blue masking tape. ANY wiring splice should be in a MOUNTED GANG BOX and in armored/flexible conduit.
VERY IMPORTANT: AFTER AN ELECTRICAL SHOCK, IF YOU FEEL ANY MUSCLE SORENESS BETWEEN WHERE YOU WERE INJURED AT ENTRY AND EXIT, AND HAVE A DECREASED URINE OUTPUT, SEEK MEDICAL ATTENTION RIGHT AWAY. THE MUSCLE TISSUE BREAKS DOWN AND ITS COMPONENTS WILL PLUG UP YOUR KIDNEYS.
I'm glad you walked away from this one. Please seek care if you don't feel right. Don't minimize your symptoms. All the best.

[Cristina1966]

OK, I concluded that my shock came from touching the bare metal in the test outlet. Clumsiness on my part. The good news is that the trailer is not shorting. The noise I heard was the rat repellent plugged in. I now know that the black line is the 110 V. The other line with a red, a blue and a white wires is the 12V output. Am I correct in assuming that red is POS, Blue is NEG and white is ground?
Cris

[A W Warn]

DC neg (-) and ground is the same thing in an Airstream.

At the battery connection DC neg (-) is usually black. Red should be (+) at the battery connection.

BUT, there is no guarantee. The color of wire and wire location can be changed. So you must know how to determine which is which.

Neg (-) will be the wire that has one end is connected/bonded to the trailer frame, regardless of color.

Pos (+) will be the wire that has connected to the (+) battery terminal or the (+) converter terminal, regardless of color.

[Cristina1966]

Hi everyone,
I reconnected the converter using all the information you provided and the electrical works beautifully. Wayward was right, I must have touched a raw wire while plugging the appliance. The good news is that the trailer is not shorted. Thank you all for the good advice,
Cris

[Wayward]

Originally Posted by Cristina1966

Hi everyone,
I reconnected the converter using all the information you provided and the electrical works beautifully. Wayward was right, I must have touched a raw wire while plugging the appliance. The good news is that the trailer is not shorted. Thank you all for the good advice,
Cris

You are welcome - and remember - one hand behind your back