I thought my wife was just reacting to the screen door's cold temperature this afternoon when she claimed it was shocking her as she touched it. I touched it and didn't get much of a buzz if any.
We've had rain here all day, so the ground is very wet. I have the trailer plugged into a grounded outlet, but the extension cord is not grounded.
I measured the voltage from the trailer skin directly to the ground with a voltmeter... yup... 110 volts AC, clean. Wonder what would happen if we were barefoot and touched the trailer... :-)
Is this normal? Would using a grounded extension cord between outlet and trailer help? Is there a problem with my trailer's wiring? The wiring is pretty simple--extension cord from outlet plugs into box in side of trailer, which connects 2 outlets inside the trailer and the A/C unit.
Posted 2007-02-01 7:12 PM (#54855 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Regular
Posts: 69 Location: Tennessee
Never use an extension cord that does not have the ground, plug your cord to a GFI plug if possible. If you plug into a GFI circuit and the plug trips, check your cord and the wiring in your trailer
Posted 2007-02-01 7:22 PM (#54857 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Location: Texas
You have a short somehwere in your trailer. Using a grounded cord is not going to solve it. You better get it checked by somebody that knows what they are doing or be prepared to have an Afro doo, or worse. No BS, this is dangerous.
Posted 2007-02-01 7:36 PM (#54858 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Extreme Veteran
Posts: 544 Location: Claxton, Ga.
Yeap, seen that before. You have a wiring issue. Hard to tell what it is from here because I can't see it. I would unplug it before someone gets hurt and have someone check it out. You can try to track it back with your meter.
Posted 2007-02-01 9:03 PM (#54863 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Expert
Posts: 2958 Location: North Carolina
RAH ....
Another thought. besides the obvious wiring short, You might have a reversed connection along with the bonded neutral wire. That would charge the trailer too.
Posted 2007-02-02 4:30 PM (#54929 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Veteran
Posts: 254 Location: Dickinson, TX
Thanks, EVERYONE, for your replies. This could be a very serious problem. I'll try a proper extension cord first, then some other outlets/generator and see if that does not solve the problem.
If that doesn't do the trick, then we're off to Silver Star soon anyway. I'll post back what we find. My hunch is that there are wiring issues from the barn, anyway. We rent a house, barn, and 10 acres... I'm finding that the whole house and other buildings here on the grounds have not been wired the way they should have been.
Posted 2007-02-02 4:35 PM (#54931 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Location: Texas
if you are going to use the process of elimination method of trouble shooting instead of getting it checked out by somebody that knows what they are doing, I would suggest you continue to let your wife open the door
Posted 2007-02-02 7:23 PM (#54946 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Veteran
Posts: 254 Location: Dickinson, TX
Okay... so I missed going to my endurance horse race this weekend due to some computer issues at work that needed my attention. Air Force... Service Before Self, HUA!?!?
With all the free time I had after arriving home this evening, I checked into the electrical issue a bit further...
On GENERATOR power, grounded extension cord or not, I get 20 volts from the trailer to the ground.
On A/C power from the barn, I get a full 110 volts from the trailer to the ground WITH a grounded extension cord.
So it looks like the problem is with the barn's electrical wiring and likely lack of a proper ground. I'll be talking to an electrician...
One question remains: is the 20 volts shown on generator power significant?
Posted 2007-02-02 7:27 PM (#54947 - in reply to #54931) Subject: RE: 120 Volts through trailer door? :-)
Veteran
Posts: 254 Location: Dickinson, TX
Originally written by Tx. Vaquero on 2007-02-02 4:35 PM
if you are going to use the process of elimination method of trouble shooting instead of getting it checked out by somebody that knows what they are doing, I would suggest you continue to let your wife open the door
That brought MANY chuckles. After having to cancel on a race I'd hoped to be heading to today due to work commitments, thanks for making my day.
Posted 2007-02-03 10:02 AM (#54976 - in reply to #54946) Subject: RE: 120 Volts through trailer door? :-)
Expert
Posts: 2958 Location: North Carolina
Originally written by racesarabhorses on 2007-02-02 6:23 PM
On GENERATOR power, grounded extension cord or not, I get 20 volts from the trailer to the ground.
On A/C power from the barn, I get a full 110 volts from the trailer to the ground WITH a grounded extension cord.
So it looks like the problem is with the barn's electrical wiring and likely lack of a proper ground. I'll be talking to an electrician...
One question remains: is the 20 volts shown on generator power significant?
The barn's wiring might not be the problem. Your trailer's short may not be leaking enough power to trip the breaker. It'll take MORE than 15-20 amps to trip the breaker with a grounded ext cord. That kind of power would light your wife's eyes with more than love for you. The tingle you feel is only several milliamps. Not even a tenth of an amp.
If your generator is self contained, and you're still measuring 20 volts to ground (which ground?) it's only because of the resistance of the trailer tires. You have a wiring problem. Your wife has you. Both are deadly serious problems. LOL
Posted 2007-02-03 11:21 AM (#54981 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Location: Texas
I had a short in the trailer before last. Apparently it started with the insulation on a wire being skinned a little during installation of the LQ. With the constant vibration it got worse with time. I had noticed a little tingle when I opened the doors, but never gave it much thought until I rode my horse up, dropped the reins and unsaddled. Before I put the halter on him he rubbed his nose on the side of the trailer and it damned near knocked him to his knees. Luckily he wasn't tied or it would have been a wreck. I always had rubber soled boots on so I guess I wasn't getting the full effect, but with wet ground and his shoes, he got it. I got it fixed pronto, but I always thought how lucky it was that some little kid walking by didn't touch the trailer. Scared the hell out of me and my horse. It is not anything to take lightly.
Posted 2007-02-03 11:24 AM (#54982 - in reply to #54976) Subject: RE: 120 Volts through trailer door? :-)
Veteran
Posts: 254 Location: Dickinson, TX
Hosspuller,
The voltage was measured the same way when the trailer was run from the barn and when the trailer was run from the generator. Tires should be out of the loop here because I measured voltage from the metal trailer door through the voltmeter directly to the ground (dirt, earth, etc.) Voltmeter probes were touching the trailer and dirt directly. If tires were in the loop for the genset, then they'd still have been in the loop for the A/C from the barn.
My explanation ^^^^^ makes sense to me... so either I didn't explain adequately in my first post OR I'm seriously not understanding what's going on... :-)
Posted 2007-02-03 1:41 PM (#54988 - in reply to #54982) Subject: RE: 120 Volts through trailer door? :-)
Expert
Posts: 2958 Location: North Carolina
Originally written by racesarabhorses on 2007-02-03 10:24 AM
Hosspuller,
The voltage was measured the same way when the trailer was run from the barn and when the trailer was run from the generator. Tires should be out of the loop here because I measured voltage from the metal trailer door through the voltmeter directly to the ground (dirt, earth, etc.) Voltmeter probes were touching the trailer and dirt directly. If tires were in the loop for the genset, then they'd still have been in the loop for the A/C from the barn.
My explanation ^^^^^ makes sense to me... so either I didn't explain adequately in my first post OR I'm seriously not understanding what's going on... :-)
I'll bet you a dollar to a Doughnut... that if you measure from trailer to the frame of the genset you'll get 110 volts. The genset is only sitting on the ground. A driven ground rod for the genset will truly ground the genset, completing the low resistance circuit. In this case, it's the high resistance between the genset and the ground that is dropping the 110 volts to 20 volts.
Posted 2007-02-03 2:44 PM (#54991 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Expert
Posts: 3802 Location: Rocky Mount N.C.
racesarabhorses, Was everything working OK before you started insulating the dressing room? I remember you saying something about some wires pulling loose while you were working around the top rail............Put them back together and fastening them down? Reckon you got a screw through a hot wire and making ground? Got something backwards so the trailer frame and - wires are hot and your + side is now the - ? Just trying to make you think back to when you first started this project, then walk your way back to where you are now. Did you cut or drill something along the way and say to yourself, "man, I hope that didn't get into any of the wiring, naw, it will be OK".........Anything along that line?
Posted 2007-02-03 6:22 PM (#55009 - in reply to #54991) Subject: RE: 120 Volts through trailer door? :-)
Veteran
Posts: 254 Location: Dickinson, TX
Hosspuller, your is a plausible explanation. I'll try to research it further tomorrow.
Retento... no screws anywhere. This is something that may have been preexisting from before the insulation project. I did replace the electrical box awhile back because the unit that came from the factory was messed up--should never have been put on the trailer to begin with, as the connector prongs were broken and moved into the box whenever a cord was connected, resulting in no connection. I'll pull the box tomorrow and have a look.
Posted 2007-02-03 10:26 PM (#55018 - in reply to #55009) Subject: RE: 120 Volts through trailer door? :-)
Expert
Posts: 2958 Location: North Carolina
Originally written by racesarabhorses on 2007-02-03 5:22 PM
Hosspuller, your is a plausible explanation. I'll try to research it further tomorrow.
Retento... no screws anywhere. This is something that may have been preexisting from before the insulation project. I did replace the electrical box awhile back because the unit that came from the factory was messed up--should never have been put on the trailer to begin with, as the connector prongs were broken and moved into the box whenever a cord was connected, resulting in no connection. I'll pull the box tomorrow and have a look.
Another wager... The cord you're using has a faulty ground or the trailer's inlet has a faulty ground. (The inlet's ground prong should be connected to the frame of the trailer)
If both of these parts had a working ground, either the genset or barn outlet should have grounded the current you measured.
Posted 2007-02-04 2:24 PM (#55047 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Member
Posts: 15
Location: Grand Island,NE
Another thing to consider before you get the electrical issue fixed is to not tie a horse to the outside of the trailer, especially with a chain...or if he/she has shoes on. Some friends nearly electrocuted their horse due to an issue like this. Knocked the horse down and luckily he survived the ordeal.
Posted 2007-02-04 4:10 PM (#55048 - in reply to #54853) Subject: RE: 120 Volts through trailer door?--AN UPDATE
Veteran
Posts: 254 Location: Dickinson, TX
Okay, I got a few minutes to take a closer look at the trailer today. BIG PROBLEM! When I rewired the inlet, I copied how it was done from the factory without realizing that there was never a ground done! More than likely, put it on my list of "things to check with the dealer" and got busy/forgot.
There are some pictures at the links below. What do I need to do to fix the problem?
You will see that the green wires (I assume they're ground) run from the connector at the bottom of the plug (flipped upside down in the picture) to the air conditioner wiring (goes into the box, then up the trailer wall). There is no connection from the green screw on the inlet to anything. Does it need to be connected to the plug/receptacle where the other green wires are connected? Does it connect somehow to the trailer skin?
Help please... thanks to all for their thoughts. I don't know how this slipped past me when I rewired the trailer box upon installing the new black connector, but can assure you the connection was never done from the factory, either.
Posted 2007-02-04 7:00 PM (#55054 - in reply to #54853) Subject: RE: 120 Volts through trailer door? :-)
Elite Veteran
Posts: 634 Location: Tipton, IN
Listen to hosspuller, he is an electrician afterall. And the way you are wired right now, you have no trailer ground from the frame. If in fact your green wire is ground, you need to run a ground wire up to your main box, then install a ground block, attach the ground from you main connector as well as your receptacles to the grounding block so ALL your outlets are grounded. If I am misstating something here please jump in hosspuller.
Posted 2007-02-04 8:52 PM (#55059 - in reply to #55048) Subject: RE: 120 Volts through trailer door?--AN UPDATE
Expert
Posts: 2958 Location: North Carolina
Hello RAH ....
You've found part of your problem. The ground wire is not connected. While anything plugged into your GFCI is protected, the whole trailer is left unprotected. (as you found out)
For a start. Connect the green wires to the grounding terminal of the inlet. Run another green wire to the frame of the trailer. All the green wires (ground) should be only connected to other green wires and to the trailer frame.
Can't tell from your photo's... the white wire should be connected to the white terminal of the inlet. These are your neutral wires. No where should they interconnect to the green wire. (As my article stated, this is proper for a house service entrance but your trailer isn't a house electrically)
This could be the other part of your problem if the inlet connections are interchanged. White wires to white terminal... Black wires to brass colored terminal.
A way to test this is, with all the internal trailer wires removed from the inlet + inlet plugged to extension cord:
1)measure between the white wire and ground... should be zero volts
2) measure between black wire and ground...should be 110 volts.
120 Volts through trailer door? :-)
