Electrical safety nazi gets shocked by his own bus

[Ed Hackenbruch]

Ahhh, come on Jim, just go stick your finger in a socket and make him feel better. 

[DaveG]

Very interesting Sean, thanks for the post.

Have you notified the folks that operate that dump station? Or the utility that operates/maintains the lines?

[boogiethecat]

Sean, Even though there is a lot of voltage "open circuit" and it was enough current to make you pay attention, I wonder what the actual maximum current could have been?  I bet it's not enough to hurt you.  It would also have been interesting to measure the voltage under a load that mimics body resistance, to see what the voltage would have been.   I bet under a load like that it would have only been a few volts at most.  "Wet" can make you feel a good tickle even with 12 volts!  That said though, your bus does present  more than a few picofarads... (and I'm guessing it was a capacitive coupling scenario, not inductive...)
Curious curious....

Cheers
Gary

[Nusa]

I'm sure Sean would have said something if there was actually something improper about the lines. What he describes is a normal effect, which anyone can easily reproduce. Florescent tubes under high voltage power lines at night is probably one you've heard about before. Here's a good picture: http://www.interactivearchitecture.org/richard-box.html

[boogiethecat]

I'm aware of the fluorescent light thing, and also aware that it's an effect but not necessarily dangerous.  Many places in Alaska experience measurable voltage potentials of 1000 volts per meter during a good aurora display, but it won't necessarily kill you, because there's not a lot of current behind it,  as might be the case in Sean's experience.  There's a large grey area between getting shocked and being dangerous.  I'm just curious where Sean's case sits... could be nasty, could just be an amazing (and excellent) story!
Cheers
Gary

[Sean]

Sorry for the delay -- my satellite has crapped out and I had to hunt for Internet access.

To Tony, Gary, and others:  Yes, I am well aware that the open-circuit voltage as read by a high-impedance DMM is not the same voltage that I would read if the bus were connected to ground through a fixed resistance (including a body).  And I suppose it might have been of academic interest to someone if I had fished out a one-megohm resistor, connected it between chassis and ground, then measured the voltage drop across it.  Buy, hey, guys, it was 108° -- there's a limit to what I was going to stand around doing out there.  Once I knew for sure I did not have a problem on board the bus, I boogied out of there (with apologies to Gary for stealing his nic).

All that being said, anyone just joining us here should know that I've been working with electricity for over three decades.  Under 300 volts I work hot; above that, I try to have the power off, or at least be wearing proper rubber gloves that I have pressure-tested myself.  So I've contacted 120, 240, and 277 VAC more than once, and I know what each feels like. A 12, 24, or 48 volt tingle would not have sent me scrambling for the meter, and of course, I knew instantly that it was 60-Hz AC.  I would estimate just from the sensation on the skin that the jolt I got was from something north of 200 volts.  The meter reading simply confirmed that.

As to whether this was "dangerous," that's hard to say.  It is quite possible that, had I actually firmly grabbed both items, the charge might have drained down rapidly and only a small voltage might have been left over to actually drive current through my body, in the milliamp range.  But I also know enough about EMF and electric fields to know that it very well might have been dangerous; more testing would be required to know for sure.  Reference Dallas's sobering story, above, wherein I am guessing the gentleman, after properly leaping from the vehicle with feet together, then fell forward onto his hands, sending thousands of volts through both.  Even three or four feet of separation on the (mostly dielectric) ground can hold that amount of potential difference when very high-tension lines are involved.

Several people have asked:  Yes, I reported this "problem" to Westworld.  They have referred it to management, although I do not really expect them to do anything about it.  Perhaps they will erect a warning sign.  It should be noted that the vast majority of RV's, which are mostly fiberglass and wood, would not experience this problem, or at least not to this extent.  It would really only be metal-frame, metal-skin coaches such as our bus conversions.  Which is one reason I wanted to report the event here -- so others can be aware of the hazard when parked near high-tension lines.

-Sean
http://ourodyssey.blogspot.com

[Dallas]

Yup, fell forward onto his hands, the fact that it's difficult to jump out of a semi tractor and get very far, I'm certain he was still within the dangerous area no matter how he landed.

[Ed Hackenbruch]

Probably should have stayed inside till they shut the power off. Unless of course the rig was on fire. Have heard too many times where a person bailed off of a piece of equipment when it tipped over or went over a bank and got pinned or run over by it, but if they had stayed in it they would have lived.