Power Lines
 

Question for you all. Have you ever been shocked on your bike while riding under high-tension power lines?

I live in Northwest Phoenix, and have a substation nearby, so I usually ride under large power lines on my routes. Sometimes when I ride under these lines, I get a painful burning or shocking sensation on my thighs if they come in contact with my frame, or maybe it's coming from my seat or something.

So the basic principle that electrical generators work on is this: a conductor in the presence of a magnetic field, and relative motion between the two, will produce a potential (or voltage. I used to be a nuclear power plant electrician....:) ) So I'm thinking that my bike is the conductor which is moving through the magnetic field being produced by the power lines and it's shocking me. It can't be a coincidence. This only happens when I ride under these power lines. So now, when I'm riding under these power lines, I'm very conscious about keeping my legs away from the frame.

Has anyone else ever had this experience?

Oh yeah, all the time. And only on metal frames, my CF bike doesn't do it.

Rumor has it, in summertime in AZ you can hold a neon tube out there and it'll glow.

Also note the amount of sag in those big wires. The amount of current being drawn heats them a bit and causes the metal to expand, so they're hanging significantly closer to the ground! Say a prayer to the gods of Air Conditioning, and support your local Palo Verde Nuclear Power Plant

The power lines
 

I used to be a lineman. How low are these lines? The magnetic field around a high voltage line - say 340 KV - is about eight feet. We used to lean into them just to make sparks jump from our fingers. (I was in college, what did I know). But, we were 100 feet up a tower when we did that.

Around a secondary line, such as the one that takes power into your house, the field is much smaller. Are there buried lines by this substation?

If the field extends so far that you are feeling it, and granted I am not an engineer so there could be a logical reason, you might want to to call your local utility and tell them. Because if you can feel it, the danger is that will arc and you will become the shortest path to the ground. Not a pleasant thing. Yes, I know you have rubber tires which ground you, but if you step off the bike, or touch something, it could be ZAP!!!

Former lineman and you dont know that rubber tires provide no protection from high voltage lines or lightning?

There's a debate about that. We wore rubber gloves, boots, etc. I hope they helped. I think it depends on the voltage.

They are the massive high-voltage long-distance transmission lines. As Sandlizrd eluded to, they seem like they sag pretty damn low. I'll try to get a better estimate next time I ride, but they can't be any higher than 25-30 feet above the road. I rode under them again this morning without getting zapped, but I was keeping my legs away from the frame. They make rather unnerving loud crackling sounds when you ride under them.

And yes, the amount of protection any rubber will afford you depends on the thickness of the rubber and the voltage. We used rubber mats and thick gloves when I was a power plant electrician. Then again, I never worked on transmission lines with hundreds of thousands of volts.

There's a stretch of road I ride on regularly that parallels some high tension lines, and I am *always* getting shocked by them

...because they screw up my wireless cyclocomputer and make it seem like I'm only going 12mph regardless of how fast I pedal! It's shocking, I tell you!

Rubber just makes one a big capacitor. lol

When I was a teen many years ago we used to go camping a couple of miles behind my house. There were massive very high voltage main transmission lines there. We would pack in some wire and coil it under the lines checking the voltage every loop and when we got a voltage reading about 110 volts we would stop and connect our light and a radio to it. We always made sure to take the coil and wire out with us as a small plane flying over the wires could find that coil of wire. Once we slept in late one morning and the plane went over and circled twice over the coil. We got out of there as soon as possible.

Ok, I'm confused. 1 - How friggin big was this coil? I'm a private pilot myself, and I'm thinking it would have to be pretty damn big for me to notice it from the air. 2 - Why is there a plane flying over the power lines looking for big coils? Are you saying the power companies patrol the lines looking for people stealing power?

I don't know if they look for people stealing power, but some power companies do use small aircraft to determine if maintenance (such as vegetation clearing) is needed on a distribution or transmission line.

Funny you mention this. I *thought* one time I noticed something like a shock when my leg hit my carbon frame when riding under these same kinds of lines...but there's no way that is possible. OK...maybe it is possible but until someone explains it to me I ain't gonna believe it happened. I think at the time I was thinking "what if" and then thought I felt something...so...even I don't believe it.

Regarding rubber...there is no perfect insulator given enough voltage.

And yes that buzzing is unnerving!

And yeah...what the hell is up with the loops of wire? I do believe the power companies inspect their lines from airplanes because the gas company I worked for used to inspect their transmission lines from the air.

What it a spark like in this youtube video?

I definitely wouldn't want transmission lines right over my house. Do a Google search on "living near power lines" and you'll get a ton of hits.

Holy crap! Maybe I'll try riding under them at night and have my wife video tape it to see if there's any sparks....

I think we're safe on the ground...mostly. Check this out...

http://www.youtube.com/watch?v=9tzga6qAaBA

Always remember, when you're on the ground you are in contact with one half of the power grid.

you think that job gets hazard pay? :eek:

Ground does not mean quite literally ground. Now I am not sure how the complete the circuit for power lines, so I cannot say that the ground is not ground, but somehow I doubt it.

Actually, I think it does...unless you're talking about DC...then it may not be literal.

In this case, ground literally means ground. The transmission system is a grounded system. In the Navy, we had an ungrounded system, but that's a whole different discussion...:)

Good f u c k ing Lord, man!!!! Find a completely new route, starting tomorrow morning!!!!!!!!!!!!

The only place where ground = ground is in the textbooks. :D

speaking of a related topic I think one of the 13 hexadecimal commandments is "though shalt not connect power to ground"...

I would attach a flux capacitor to your bike, you never know!