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General Forestry => General Board => Topic started by: Sawyerfortyish on May 28, 2012, 08:31:18 AM

Title: EMF meters
Post by: Sawyerfortyish on May 28, 2012, 08:31:18 AM
Anyone know anything about emf meters? No I'm not ghost hunting. I have a 250kva high tension power line running through my farm. Public service electric and gas wants to double it. They want to replace the 80' towers with 180' towers and increase voltage to 500kva. My house is 100yrds from the line i want to take some readings in differant locations on the farm before and after.I dont know enough about these meters to pick one out. I need one to pickup high readings as the lines cross over a hill on my farm they are only 20' or less from the ground.I looked on ebay and there are so many differant models of emf meters I feel like a city office worker picking out a chainsaw for the first time do i get the red one the green one or the expensive orange one :D.thanks for any help
Title: Re: EMF meters
Post by: Kansas on May 28, 2012, 09:36:53 AM
If you are thinking of a possible lawsuit, I would have someone independent come in and measure now that has credentials. Then have them do it after. Get the results. 100 yards isn't very far. I have heard too many stories, plus have a few of my own. If you just do it yourself, it won't stand up in court.

Was mowing hay once around some on a foggy day. Every time I crossed under them, something didn't feel right. And just out of high school, had a few calves on pasture that they went through. Had two die. Both near under the lines. Had the vet post them. He couldn't find a thing wrong. Coincidence? Maybe. Maybe not.
Title: Re: EMF meters
Post by: Sawyerfortyish on May 28, 2012, 10:03:10 AM
No lawsuit there gonna do it anyway. they need to build almost a mile of road on me and we agreed on a square ft price 2 years ago and they paid us. Everyone else is fighting it. PSEG is winning and they even have a bill in front of Obama if he oks it they'll crush everyone in the way. But if everyone can stretch out the lawsuits another 3 years we get paid again.
  I want the meter for my own use. PSEG has told me that going up higher and reconfigureing the differant strands of wire in a certain way will actually lower the emf reading
Title: Re: EMF meters
Post by: Kansas on May 28, 2012, 10:14:10 AM
The lawsuit isn't for now, but down the road so to speak. What is really true, and what isn't I don't know. If they come out with a comprehensive study in 5 years down the road that there are significant health hazards, it would lower the value of your house, maybe to near zero. That is why I would plan ahead.

You might read a little of this article.

http://emf.mercola.com/sites/emf/emf-dangers.aspx
Title: Re: EMF meters
Post by: SPIKER on May 28, 2012, 10:35:21 AM
A couple tests you can do with in-expensive items, use a 4' or 8' fluorescent bulb and hold it in your hand on one end hold it up pointing towards the lines and see how bright it gets :o   Next take a 3' hunk of rebar or pipe and drive it into the ground take a metal cloths hanger bend it straight attach to a short wood post and attach a VOM (ohm meter) set to AC voltage (a cheap one works better than expensive ones for this test.)   hold the wire at a known height say 8' check voltage between the wire and the rebar/pipe.   the wire acts as an antenna picks up the EMF by induced voltage the wire should be held in-line with the power lines.   The longer the wire on the stick the more voltage you will get.   in many remote locations stringing barbed wire can be an issue if run under power lines, and even used this power to run pumps etc. 

Mark 
Title: Re: EMF meters
Post by: Kansas on May 28, 2012, 10:40:59 AM
You serious about the fence and fluorescent bulbs? I never heard of that.
Title: Re: EMF meters
Post by: SPIKER on May 28, 2012, 10:49:43 AM
Kansas:

Yep give it a shot and see.  I suggest not holding onto the wire hence the wood handle ;) :o  the higher the tension line voltage the brighter the bulb too, (not the guy holding it though  ::) hahaha..

Used to play "Light Sabers" under them as kids (wonder if that is why I'm a bit off?)

Mark
Title: Re: EMF meters
Post by: Clam77 on May 28, 2012, 07:52:23 PM
If you have a smartphone, they make EMF measuring apps for them.  I got one for mine- it's fairly accurate inside a steel building with running machinery- I presume it'd work pretty good outdoors too.
Title: Re: EMF meters
Post by: Brucer on May 29, 2012, 12:20:07 AM
The most important question -- AC or DC?

If I remember correctly (no guarantees), EMF meters & the fluorescent bulb trick will only work with AC current.
Title: Re: EMF meters
Post by: Ronnie on May 29, 2012, 02:27:04 AM
I am a substation electrician and  spend 8 hrs a day in substations, in close range with voltages up to 345,000 volts. I am constantly exposed to transmission line voltages and I have been doing it for 8 years now. We have a Christmas party every year and all the retired guys show up many of them in there 80's. Never heard or seen any adverse reactions to EMF and I am in it all day. Our work trucks will shock you from induced voltage in the substation. I was worried about it when I first took the apprenticeship, I don't worry about it anymore. There are 56 people in our department and we are all healthy. On our farm we are very concerned about health and raise all of our food as close to organic as possible. I think the crap they sell at the grocery store will kill someone long before induced voltages from transmission lines will. I understand it worries some folks. I was just letting you know that I haven't seen or heard about any health problems and we are exposed to it way more than anybody else.

Ron Paul

Title: Re: EMF meters
Post by: Ron Wenrich on May 29, 2012, 05:26:38 AM
There is a high voltage line running through my property, and its about 150 yds from my house.  I've lived here since 1977.  I used the same logic that if anyone would have health problems from EMFs, it would be the guys that work around it all the time.  Glad to hear that my logic was right.

I've heard about the fluorescent light trick, but have been to cheap to buy he bulbs to try it.  A friend of mine said I could use an induction motor under the lines and get free electric.  He's an electrical engineer. 

The worst we get is that you can hear the lines crackle when there is a snow.  Folks used to say that lightning would travel on the lines, but I have yet to see that.   
Title: Re: EMF meters
Post by: MHineman on May 29, 2012, 07:23:14 AM
Quote from: Ron Wenrich on May 29, 2012, 05:26:38 AM
I've heard about the fluorescent light trick, but have been to cheap to buy he bulbs to try it.

Folks used to say that lightning would travel on the lines, but I have yet to see that.
I've also heard about the flourescent bulb, but have never gotten up the nerve to try it.

  I heard a long time ago that the towers have the 3 phase power lines at the bottom (middle and both sides) and the 2 wires on top of the towers are connected to ground.  That way lightning strikes would hit the ground wire and not the powered wires to minimize the surges to electric company equipment.

  I'm going to check out the voltage between the ground rod and an insulted wire.  I was planning on building a high tensile fence near a 250+ KV line.  Since some of the wires are usually setup for a hot wire and are insulated, they could be very dangerous.
  I guess I could come up with a way to short the wire to ground instead of supplying a charge to get the periodic pulse a hot wire needs to be safe and run the fence for free.
Title: Re: EMF meters
Post by: John Mc on May 29, 2012, 05:16:01 PM
EMF fields generally follow the inverse-square rule: that is, the strength of the field varies inversely with the square of the distance. So if you double the distance, you cut the field strength to 1/4.  That would be for the same voltage. Since they are doubling the voltage, you'd double the field strength, but still end up with a net 1/2 the field strength you started with (actually less, since they are more than doubling the height).
Title: Re: EMF meters
Post by: Al_Smith on May 29, 2012, 05:47:53 PM
I've never seen it done but I imagine the flourescent tube trick works about like a neon bulb type tester .

We used a neon thing that would read right through the insulation of 13.5 KV cable .

There's a bunch of west coast linemen that work those 765 kv transmission lines at potential .I think they're all crazy myself but I haven't heard if there's been any health problems although it's suspected they might glow in the dark but that's never been confirmed
Title: Re: EMF meters
Post by: Al_Smith on May 29, 2012, 05:59:26 PM
More .During I think the winter of 1986 I worked a 42 miles section of 20 inch high pressure natural gas pipeline .A portion of it was buried right under I think a 138 KV transmission line .

Like typical underground pipe it was insulated to help prevent galvanic reaction .At the terminal end of that pipeline as well as other portions on each valving site I had to thermite weld a 4/0 ground wire .

Not thinking  the pipe would in essence become a giant capacitor I filed through the insulation and got the pee zapped out of me  much to the delight of the pipeline crew .They knew what would happen . :D I donned my high voltage gloves from that time forward on every "cad weld "
Title: Re: EMF meters
Post by: Sawyerfortyish on May 29, 2012, 08:32:21 PM
Thanks to everyone for the world of info.I heard the one about the flourescent light trick but never tryed it.One neighbor asked PSEG about a cattle fence he wanted to put under the line and was told not to. Never thought about it picking up electrical charge.I'm also sure that if there were health issues from EMF that OSHA would be all over it.  One of the longest spans between towers on this line is on my farm almost 1/2 mile and yes what strange sounds come from the cables stretching with an ice load and can be heard from a long distance away.I have a picture window view of the tower line and a tower on top a tall hill and have never seen lightning strike it or travel across the wires.You would think that a big metal tower with all that wire atached sitting on top a mountain would atract lightning like a magnet but nope watched it for years never seen it get hit.
Title: Re: EMF meters
Post by: SPIKER on May 29, 2012, 09:43:17 PM
Ive seen 2 transformers blow up and one high kv line short / break and drop.   it happened in winter storm circa 1994 light up the town for sure.    nice ball of plasma about diameter of a 1980's sat dish ~8' plus as seen from 400+ yards away.

to pull power out is actually stealing as the EMF created by the electrical flow but pulling power out of the field means more power is drawn out of the lines to feed the field.    cable/wire running parallel under the lines closer to the lines deeper in the EMF field the higher the pulled voltage will be.   in theory you can almost match the transmission lines voltage by having longer and closer parallel power cables.   Just expect a power company person to knock on your door pretty quickly with a officer standing beside him...

Mark