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View Full Version : DON'T TOUCH THAT LADDER!!!!!!!!



Vern Heiler
05-20-2010, 02:28 PM
After you have expressed your concern for my safety, I will post another picture.

Jerry Peck
05-20-2010, 06:16 PM
Hard to read your meters, but ... see that large greenish box down the street in the first photo? You are probably standing near another one, right?

Think power company underground service lateral with two ungrounded conductors and one grounded conductor/grounding conductor along with using the earth between the houses and the transformer as a secondary return path because the ground return path is not required to be an insulated conductor back to the transformer.

Remember, all current tries to find its source, and its source, in this case, is the closest transformer ... from ALL of the houses supplied by that transformer.

Okay, now ... ;) ... how big was the shock which caused you to bring out the meter?

Do you, perchance, have a "grounding strap" mounted to your car to reduce static electricity while driving? If so, you were "energizing" your car (which, luckily for you, has a thin insulating coat of paint on it) and the ladder tied to the car (presuming there is some metal-to-metal path I do not see in the photo). If you do not have anything which grounds your car to ground, then I am having a problem visualizing how that could happen with the car being insulated from earth by its 4 nice insulating rubber tires.

Bill Kriegh
05-20-2010, 06:19 PM
Where are the analog meter readings? :)

Jerry Peck
05-20-2010, 06:22 PM
Where are the analog meter readings? :)


Bill,

That was my first thought too, then I noticed that the last photo shows what looks to be ac current readings.

John Arnold
05-20-2010, 06:47 PM
That's why the ladder on top of my Subaru Outback is fiberglass!

Vern Heiler
05-20-2010, 07:47 PM
The meter was brought out purely out of curiosity while waiting for the Realtor to arrive. The home has a supplemental grounding system installed to reduce the "induced voltage" effect of near by 525 kilo-volt transmission lines. The buyer was concerned about what the system was and what it was for. I have disclaimers regarding lightning protection and this falls in the same category. I explained it as being similar to the vandagraph experiment we all remembered from high school. Lots of voltage and little current. The induced voltage was 500 volts a/c on my ladder but you could not feel anything. (the 17.4 amps was really milli amps, but who was going to notice :D )

Jim Luttrall
05-20-2010, 08:34 PM
Believe it or not, I was expecting to see ah overhead power line photo posted after reading your first post. I have often wondered if your land paralleled those high voltage lines if you could induce enough power to be worth the trouble. Figure a wire 100' long above the ground hooked to the appropriate step down transformer... I know, I know, the power company would not like it but would it not be wasted energy?:confused:

Bill Kriegh
05-21-2010, 06:52 AM
Years ago I built a couple of traffic signals very close to and under 250KV and 500KV power lines.

The metal poles would shock you enough to hurt and required the use of "hot" gloves to work on. The light bulbs buzzed until you had them screwed in enough to touch the center contact. All this with pole bases buried 12 feet and they couldn't have been grounded better.

You couldn't pay me enough to live close to one of these lines simply because of the shocks you can get from the induced current. Pulling a large wrench out of a tool box can be an eye opening experience around them.