Electrical tingle

[TAKAFOOMI]

Hi guys. I'm a newbie so I'm hoping you can point me in the right direction. We just bought a used 2006 Sprinter 299LH(I think). Today I was de-winterizing it... And noticed when I touched water and metal that I felt a light electrical tingle , like a 9V battery sensation.. Or in this case, 12 v. I figure it must be a grounding issue somewhere.. But I didn't see anything obviously disconnected. This happens whether I am connected to shore power or run with my battery (although I have to say my shore power was connected the whole time, but I also fully connected the battery + & - connections). The electrical panel does not show any issues...

Is this normal? I'm guessing 'no'. Help!

[CPE]

Definitely NOT normal! I suspect AC ground problem. Totally-- disconnect AC power connector on trailer and see what happens(use a meter not your hand to feel!). Unlikely you are feeling 12volt ground issue. My guess is grounding issue with connector or shore power supply or inside trailer.

[TAKAFOOMI]

Thanks CPE. The trailer itself was sitting in a wooded lot for years without moving. I'm hoping that it's an easily identifiable, easily accessible loose connection near the shore power connection. Any idea as to where I should physically look first?

I dont know where to look inside the trailer itself for an issue.. it was well kept/clean so I dont think anything went wonky there (I hope).

I'll also test my outdoor receptical for fun..

[SteveC7010]

Originally Posted by TAKAFOOMI

Thanks CPE. The trailer itself was sitting in a wooded lot for years without moving. I'm hoping that it's an easily identifiable, easily accessible loose connection near the shore power connection. Any idea as to where I should physically look first?

I dont know where to look inside the trailer itself for an issue.. it was well kept/clean so I dont think anything went wonky there (I hope).

I'll also test my outdoor receptical for fun..

Definitely a 110vac problem. DC doesn't tingle.

Start with the receptacle. If you have one of those handy little plug-in testers with the three lights, use it.

Test every receptacle in the trailer.

Disconnect the shoreline and open up the electric panel where the AC circuit breakers and remove the cover plate which will expose all the 110vac wiring connections. It might look something like this, but not nearly as neat:

Check EVERY connection for tightness. See if you can spot any wires that are hanging loose in there.

What's happening is that the hot leg of the 110vac is partially shunted to the skin and ground of the trailer. Your body is acting as a conductor between that and real ground.

If you're not comfortable with troubleshooting 110vac problems, see if you can find an electrician who is OK with working on RV's. Many of them think RV's are from Mars and don't realize that the AC side of an RV is just a smaller version of a home electrical system.

[TAKAFOOMI]

Steve - thanks for your help. Maybe it's coincidence but I needed to replace a 15amp fuse on the DC side for a few of the lights - very easy to identify with the LED indicators in the panel.. However, there's still one light out - a white light on the front exterior of the trailer. The prior owner mentioned he'd fixed it.. Any chance that's related?

Regardless , I'll check the system tomorrow AM... I hope it's easy to see something obvious..

[crash]

Sounds like a ground problem.Check to make sure your sure power source is properly grounded.

[TAKAFOOMI]

So.. Heres a quick update. I used my multimeter and detected about 12 - 18V AC at points on the frame, and a little more at the bottom of the doorframe(s) sill. I plugged a 3 light tester into my source power, and it checked out OK. I plugged it into the trailer outlets and seemed to illuminate the ground light weakly.. And the neutral light brightly.

Within the main breaker panel, I looked briefly at all the connections... Everything seemed to be connected/nothing obviously loose. I flipped breakers for fun , and when I flipped the one labeled GV, which I think was for the inverter (when it was off, the high pitch noise from the inverter got quiet) the 2 yellow lights on the tester in the GFCI near the panel fully illuminated.. So I think the ground short may be in that circuit. Somewhere. Maybe. But where do I look / how do I find the culprit? Help!

[B&T]

Taking the fact that you were de-winterizing when this problem showed up I assume you just filled your previously empty hot water tank with water. I have seen instances where this hot skin symptom was traced back to a defective 110v water heater element. Just a guess on my part but something you might consider.

[TAKAFOOMI]

How would I test the hot water heater element? When I started the heater it did heat up the water tank nicely.. So it appeared to work...

[B&T]

In this case, I would completely disconnect the ac wiring going to the HW heater-->both Hot, ground and neutral. Then check to see if the skin is still hot. If the voltage on the skin goes away when the HW heater wiring is removed then i would suspect a bad heater element.

If it turns out that it is not the HW heater circuit then I would choose other electrical circuits to disconnect untill I find the problem circuit causing the hot skin.

If you can identify items in the camper that are powered by your "GV" breaker and disconnect the AC wiring to them one at a time while checking for the problem each time it might help to narrow your search for the problem.

[TAKAFOOMI]

So today I removed the electrical panel, checked for any loose connections - none . Then I crawled under the body of the trailer and checked for disconnections or obvious wear marks - nothing. Then I repaired a 12vDC lamp which needed fixin in the front of the trailer hoping that somehow it was the culprit - nuthn. Then I disconnected the power from the water heater, retested the voltage on the skin... Same voltage was there. I also opened up the refrigerator to make sure nothing was squirrelly there - nope. I started to open the GFCI recepticals and other non GFCI recepticals to look for disconnects or crossed wires.. Nothin. Even opened up the light fixtures in the bump out - nothin. I am assuming the inverter is working properly or I wouldn't have 12v accessories while plugged into 120v AC.

I have not yet swapped the 30a to 15a adapter.. That's my last card trick to try before I bring it into service . Can anyone else think of something a newbie like me would miss?

[jsmith948]

Inside your RV, adjacent to where your shore power cord plug or 'mousehole' is, - behind a drawer or behind a removable panel at the bottom of a cabinet is a junction box. Our junction box is located under the stereo in the rear wall. This is where our 30 amp power cord is tied to the orange romex that then runs foeward to the power panel. With the power unplugged, check inside the junction box for loose connections. On our Cougar, I found that the wire nut was loose on the ground and the neutral wire. If all is ok there check to be sure that the plug you are connecting to has a proper ground. Your RV relies on the recepticle being grounded. Hope this helps - good luck

[joeyb]

I know that tingly feeling. I had the same feel on my last trailer (Holiday Rambler Aluminum Siding) I found it at 14v to ground coming off of bumper. Long story short my battery was boiling when plugged into shore power (shorted plate?) Replaced battery and it seemed to solve. All working normal again. Unsure if it was a backfeed traded in shortly after.

[therink]

I had the exact same problem at a campground once and it drove me crazy. I could not find the source. Once I got home the voltage was gone. After doing some research, I realized that I was parked within a couple hundred feet of over head high voltage transmission lines and it was bleed off from these lines causing the low voltage in my frame. Sounds crazy but it was true.
Steve