DC Short? Odd Tingling on Door Frame

[Airstream Dad]

Greetings!

A very rainy night and damp morning here in PA, was climbing into my 2005 International in bare feet and noticed a slight tingling when grabbing the door frame. Unplugged the trailer from the pole, still there, tried testing it with my multimeter, black tip in the wet earth and then when touching red to parts of the frame, showing 0.48 set to 20V.

Any tips on what's going on? Would a DC short somewhere cause tingling when in bare feet? Is this a function of dampness or is there a serious issue?

Thanks,

Jim

[Zil]

0.48, less than 1/2 volt will not cause tingling. Could there be any other source, maybe a capacitor?

[polarlyse]

I was plugged into a 20a outlet using an extension cord while visiting a friend a few years ago. When reaching into my rear storage compartment I felt a slight tingle in my forearms when in contact with the compartment door frame. Never felt it before or since. I keep it plugged in using an extension cord and a dogbone 20a adapter while parked at my son's house. I suspect 2 possibilties here. Either a bad extension cord at my friends house or his outlet may have been wired incorrectly. Havent't been back to try and duplicate or use a different extension.

[HowieE]

DC is not known for causing tingling.

Do you have an inverter or any solar on the trailer.

Something is generating an AC signal

[mhilley]

Sounds a bit nutty but are you near a radar installation? Are you near a transmitting tower(TV) or a cell tower? You can tell if it is radar by hooking an analog meter to the skin and to ground. The needle will sweep up when the radar comes around. Please don't laugh! I have seen it. Could you be near a high voltage power line? You can pick up things like you have by inductance. That is loosely defined as two conductors close by, the voltage transferring from the active conductor to the neutral conductor (like the skin of your trailer).

[Rich W]

Originally Posted by Airstream Dad

Greetings!

A very rainy night and damp morning here in PA, was climbing into my 2005 International in bare feet and noticed a slight tingling when grabbing the door frame. Unplugged the trailer from the pole, still there, tried testing it with my multimeter, black tip in the wet earth and then when touching red to parts of the frame, showing 0.48 set to 20V.

Any tips on what's going on? Would a DC short somewhere cause tingling when in bare feet? Is this a function of dampness or is there a serious issue?

Thanks,

Jim

Was there any lightning present in the area? If so, you may have experienced a streamer coming from the ground, trying to connect to a bolt in the sky.


A picture of two brothers with their hair standing on end taken in 1975 shows what can happen just moments before lightning strikes.

[DaveFL]

Originally Posted by HowieE

DC is not known for causing tingling.

Do you have an inverter or any solar on the trailer.

Something is generating an AC signal

Try a 9v dc battery on the tongue
Sweat or high humidity and your hand touching 12v positive lead tingles.
No ac anywhere near the car when I experienced it.

[TomKirk]

Static electricity. You're picking up charged particles from someplace.

Tom

[macofpei]

When winterizing my Stream, laying on the ground to open the water drains, I always get that tingling. I am usually plugged in to 15 amp service using a good extension cord and adaptor. I know I have a problem but can't find it.

[HowieE]

Originally Posted by macofpei

When winterizing my Stream, laying on the ground to open the water drains, I always get that tingling. I am usually plugged in to 15 amp service using a good extension cord and adaptor. I know I have a problem but can't find it.

Yours sounds like a floating ground. Get a 3 prong receptacle tester and check the source. I am assuming that the circuit is 3 prong.

[GCinSC2]

Worth watching.

https://m.youtube.com/watch?v=Y8h64X33aKg

Rv hot skin electrical testing. No matter, worth watching.

[sajohnson]

Originally Posted by GCinSC2

Worth watching.

Rv hot skin electrical testing. No matter, worth watching.

This is a good video. Mike Sokol is a sharp guy and knows his stuff.

Everyone who owns or uses an RV or trailer should watch this.

(BTW -- this video was shot just a few miles from my home at a local RV dealer -- Beckley's.)

[sajohnson]

Originally Posted by macofpei

When winterizing my Stream, laying on the ground to open the water drains, I always get that tingling. I am usually plugged in to 15 amp service using a good extension cord and adaptor. I know I have a problem but can't find it.

Hi Mac,

Not to be an alarmist, but what you are describing is potentially deadly.

Watch the video for further explanation.

You really should correct the problem before using the trailer again (at least before using it with shore power connected).

Many people are tempted to think, "Well, it's just a little tingle...". The thing is, you or someone else may be better grounded (a more 'attractive' path to ground) next time, and/or what may be a slight fault now might very well get worse.

[sajohnson]

Originally Posted by Airstream Dad

Greetings!

A very rainy night and damp morning here in PA, was climbing into my 2005 International in bare feet and noticed a slight tingling when grabbing the door frame. Unplugged the trailer from the pole, still there, tried testing it with my multimeter, black tip in the wet earth and then when touching red to parts of the frame, showing 0.48 set to 20V.

Any tips on what's going on? Would a DC short somewhere cause tingling when in bare feet? Is this a function of dampness or is there a serious issue?

Thanks,

Jim

Hi Jim,

I have to admit, your experience has me stumped.

I have the same question as HowieE -- do you have an inverter?

[towmommy]

Before replacing the univolt system in my 79 sovereign we would routinely get a live current when touching the front door or frame and either step or ground. After replacing the
Univolt a few years ago the problem disappeared. I believe it was a poor ground issue but am really not 100% sure . The annoying buzzing in the speaker system stopped as well. Your unit is pretty new (comparatively speaking) I would most certainly call the experts.

[Airstream Dad]

Thanks! Yes, I do have solar on the trailer.

[Airstream Dad]

OK, I've got my trailer back home and connected to my shore power.

I dug out my AC outlet tester pen (just like the video, except it doesn't go off until I still it right into the hot side of an outlet), went outside and tested the door frame, steps, etc., around it - nothing, light stays green.

I did connect my multimeter to it and set it again to DC, 200V, it's still showing a little bit of charge, maybe 0.18. Of course, it hasn't rained since last night and I drove it 200 miles, so maybe a problem dried out.

Someone asked about the solar panels, I wonder if there's a bad connection there somewhere.

Cheers,

Airstream Dad

[NavyCorpsman]

Do you have florescent lighting of any type or size in the coach?

[sajohnson]

It is unlikely that a low voltage solar power power system can produce enough voltage to cause a shock.

Also (just FYI) anything under 50Vdc is considered safe:
Small Contact Voltage Exposures Not Lethal to Human | Shock & Electrocution content from Electrical Construction & Maintenance (EC&M) Magazine

[jimmbob]

I have the same issue when plugged in house 120volts. A little bite when changing a tire leaning against the AS. Please keep me updated. Just got "Lucille"last fall. Beside lots of leaks she rocks!!! Took her on maiden voyage last weekend. What a learning experience. 400 miles round trip. Back home safe and sound!