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[Mike Sokol]

Two days ago a 3-year-old boy was electrocuted when the touched the skin of his family RV in the back yard. I was contacted by the local newspaper for an interview about how an RV with a hot-skin condition can kill you. And here's the video I just posted about this earlier today for RVtravel.com. http://www.youtube.com/watch?v=opuult8jMOo&feature=youtu.be

This is exactly what can happen with an improperly bonded/grounded stage or sound gear. Let's be careful out there.

[Mike Sokol]

I just talked to the electrician who was on the scene of this accident. He said that the home outlet the RV trailer was plugged into was  rusted and used a 30-amp to 15-amp dog-bone adapter. He measured 37 volts on that outlet ground even when nothing was plugged into it. I'm guessing that something on that branch circuit was leaking some current into the EGC that had lost its bond back at the service panel. However, there was probably insufficient current from that source to cause the electrocution.

The RV trailer had an external outlet box with the screws missing and the receptacle hanging out on the wires. The electrician said it looked like the black wire had made contact with the metal side of the Airstream trailer. That's probably what hot-skin electrified the RV with full circuit breaker current. Of course, without a low-impedance safety ground path back to the service panel's bonding point, the circuit breaker never tripped.

The electrician confirmed this was an Airstream trailer, so that's bare metal body with 120-volts on it. Pretty scary when you think about it.

I can remember plugging my bass amp into a receptacles hanging out of wall in really seedy clubs. And at least a few times we got some pretty serious shocks while doing so. Nowadays we all know better (or should) but the dangers are still around us.

[Jeff Bankston]

wrap some electrical tape several times around the sides of an outlet in a club. at least that will cover the live parts. if it were me i would tell the owner i have some screws and i would screw it back in unless the screws are broken off in the holes and cannot be gotten out. i keep a #6 and #8 screw kit with me.

[Bob Leonard]

That's a pretty sad story Mike. Owners of Airstreams generally have a bit more dough than the rest of us bums, but you travel through life and often find money often replaces common sense. Perhaps the owner thought all was well with his outlet, but regardless, using a meter or calling for an inspection once in a while might have saved this kids life.

[Jeff Bankston]

That's a pretty sad story Mike. Owners of Airstreams generally have a bit more dough than the rest of us bums, but you travel through life and often find money often replaces common sense. Perhaps the owner thought all was well with his outlet, but regardless, using a meter or calling for an inspection once in a while might have saved this kids life.

i know a guy that was given a old 1960's airstream. the interior is worn out and trashed. the outside is in exelent condition. its a twin axle and has the original tires. i pulled it from graybull wyoming to nevada about 7 years ago. i picked it up at night i didnt know it had the original tires until after i had pulled it about 300 miles. i was following the owner in his truck. he hasnt done anything with it due to lack of money so it will probably always have a trashed/worn out interior. maybe that was the casre here, some relative gave it to them or they inherited it.

[Mike Sokol]

That's a pretty sad story Mike. Owners of Airstreams generally have a bit more dough than the rest of us bums, but you travel through life and often find money often replaces common sense. Perhaps the owner thought all was well with his outlet, but regardless, using a meter or calling for an inspection once in a while might have saved this kids life.

I have more insider info which the sheriff and reporter asked me not to publish in my interviews, but I can share it here. They tell me the dad had felt a shock from this trailer the day before and didn't do anything about it. How devastating to lose a child from a preventable accident. So please, if you feel a shock from a mic or guitar or whatever, don't wait until later to fix it. Power down and figure it out RIGHT NOW.

Also, since you're already on this forum you all know how important electrical safety is. And I hope you realize what a tremendous resource we have here. I consider all of you to be part of our industry brain trust that's willing to share your expertise about pro-audio power distro and grounding with anyone who asks. I don't think there's another forum quite like this anywhere...

[John Roberts {JR}]

+1, those of us who work around electricity and have survived inadvertent shocks over the years can be a little too blase about the shock hazard, I know I was (am?). Electricity can and does kill...

JR

[Stephen Swaffer]

My first thought when I read this was "maybe we need an 'assured grounding conductor program' for RVs."  But that just shifts responsibility-we each must take the responsibility-I hesitate to say that publicly, since the dad in this case will still be reliving this event years after we have forgotten the story.

When I wire a home, our inspectors check the wiring on every receptacle with the expectation that the wiring will remain more or less untouched for quite some time.  RVs and temporary sound share the trait that their wiring will be disconnected/reconnected many times in the course of a season.  "Hot"s and neutrals are self testing in that if they aren't connected something will  obviously be wrong and we will go looking for the issue.  Not so with grounds-if they are not right and we do not test them the problem will remain undetected until it presents itself hopefully as an annoying and potentially hazardous tingle-or perhaps tragically.  Verifying grounds ought to be part of setup just like a mic check.

[Mike Sokol]

When I wire a home, our inspectors check the wiring on every receptacle with the expectation that the wiring will remain more or less untouched for quite some time.  RVs and temporary sound share the trait that their wiring will be disconnected/reconnected many times in the course of a season.  "Hot"s and neutrals are self testing in that if they aren't connected something will  obviously be wrong and we will go looking for the issue.  Not so with grounds-if they are not right and we do not test them the problem will remain undetected until it presents itself hopefully as an annoying and potentially hazardous tingle-or perhaps tragically.  Verifying grounds ought to be part of setup just like a mic check.

I agree. In an effort to improve the safety grounding in RV campgrounds I've proposed a yearly or bi-annual test on all pedestal outlets using something like an Amprobe INSP-3 or SureTest Analyzer. For those of you who've never used one, they do a single-cycle pulse test down the ground line which gives you an impedance value in ohms. Anything more than 1 ohm suggests a too-long or poorly connected EGC. Anything less than 1/10 of an ohm suggests a bootleg ground (intentional short between the neutral and ground in the receptacle instead of running a proper EGC ground wire). These testers also tell you the voltage drop with percentage for 15 and 20 amp loads, as well as a simple 3-light ground test.

Be aware that none of these Ground Impedance Impedance Testers (GLIT's) will detect an RPBG (Reverse Polarity Bootleg Ground), where the hot is at ground potential, and the neutral and ground are both hot. Most of you have probably already seen this, but for you newbies here's a link to my article about this mis-wiring condition: http://ecmweb.com/contractor/failures-outlet-testing-exposed

[Frank DeWitt]

I agree. In an effort to improve the safety grounding in RV campgrounds I've proposed a yearly or bi-annual test on all pedestal outlets using something like an Amprobe INSP-3 or SureTest Analyzer. For those of you who've never used one, they do a single-cycle pulse test down the ground line which gives you an impedance value in ohms. Anything more than 1 ohm suggests a too-long or poorly connected EGC. Anything less than 1/10 of an ohm suggests a bootleg ground (intentional short between the neutral and ground in the receptacle instead of running a proper EGC ground wire). These testers also tell you the voltage drop with percentage for 15 and 20 amp loads, as well as a simple 3-light ground test.

I wonder if one or more of the high end RV builders could be sold on including one of these with a new rig (and training on how and why to use it.)  We care about our customers. Our product is safe but do you know what you are plugging it into ETC.

Many of the high end rigs have computers running systems.  Could a test on power transfer be programed in? 

My thinking is to get them out there.  The RV owners could then show them off.  Kind of like blind spot detection and back up cams.  First in the high end, then in the middle ETC.

[ProSoundWeb Community]