EMF Exposure

[Scottie]

Yes, whatever is distributed to the breakers needs a filter so if the panel box bus is 3-way to the breakers/circuits, then you will need 3 filters – preferably close to the box. It also means that you’ll need 3 more breakers.

Okay.

If the cable is shielded then its as good as BX. If the outer layer is not metalized, then it is not shielded.

No, it's not shielded. I've never seen or heard of such a thing here, even in my French "Big Book of Electricity".

Grounding is one of the commonly overlooked areas – even by the power folks. Neutral and grounds should be bonded ONLY at the service entrance panel – nowhere else. You want all current headed to ground to actually get there (the voltage drop has already occurred across the load). The resistance looking back towards the transformer that feeds the house may not be all that low. So you want a very low resistance path to ground – the ground rod. If this resistance grows (with time, age, etc), then current will return through the ground/neutrals setting up ground loops around the house. One theory is that this may exacerbate the solar inverter noise as well (I have no explanation for that if true).

Here they do stuff a bit differently. You never bond neutral-ground at the panel. The neutral at the local transformer is grounded, and it's strictly verboten to bond neutral to the local panel ground in an installation. They also are rather emphatic about not bonding ground to water pipes and that kind of thing.

Will the flashing red "HOW?!" light in my head finally turn green?! STAY TUNED!

Mine probably won’t until I see some real before/after measurements independent of the meter.

Well, we can dream...

 

[Scottie]

You want to bond the grounds on the ac side of the inverter and the normal feed. It's not a good idea for systems that get connected together to have 2 separate grounds. If they are piped into eachother, or some transfer switch then you are bonded.

[...]

In the 2010 code and up, bonding has become more important than grounding. If the ground potential is not even across rods (like using separate rods for solar, etc), you get current loops flowing through the earth which you mention.

I'm still confused why the AC output of the solar system wouldn't be bonded to the main panel - which it feeds power into the grid??

The installation at the Farm is that there are 2 main breakers and 2 meters, both installed by the power company and you're not supposed to touch any of that. Of course, people snip off the little plastic tabs all the time, and the power company doesn't seem to care much, as long as you haven't upped your supply current in the main breaker without telling them so they can bill you for the higher service. This is all the responsibility of the power co, and it's installed in a box on the outside of the house.

Anyway, there is no ground-neutral bond at the main breaker/meter either. Also, our main breaker/meter at the house here has no ground - just 3 phases + neutral. I was peaking over the power co's tech when he replaced our main breaker a few years ago. It's all pretty simple.

But back to the Farm... The solar panels seem to feed power back onto the grid at the point where the power co's cabling comes in to feed the main breaker and meter for the house. All the wiring for this is concealed, so it'll prolly be impossible to check any of that thoroughly.

OH! Hang on a minute... There IS a ground for the solar panels, because I just remembered I wired it to the main ground at the downstairs panel...
That was awhile ago. I forgot!

So, the house + panels share the new ground I put in (which is better than what the code requires for our area).

Lessee...

The Frenchie code says that solar panels must have a ground, blah blah blah, prevents galvanic corrosion of the frames holding the panels, noise produced by solar panels, blah blah blah, and if you have 2 grounds, you should instead bond them together to a single ground.

Well, that figures. No mention of DP, of course! Well, we can experiment with a separate ground(s) for the panels if necessary.

 

[LQB]

You want to bond the grounds on the ac side of the inverter and the normal feed. It's not a good idea for systems that get connected together to have 2 separate grounds. If they are piped into eachother, or some transfer switch then you are bonded.

[...]

In the 2010 code and up, bonding has become more important than grounding. If the ground potential is not even across rods (like using separate rods for solar, etc), you get current loops flowing through the earth which you mention.

I'm still confused why the AC output of the solar system wouldn't be bonded to the main panel - which it feeds power into the grid??

The installation at the Farm is that there are 2 main breakers and 2 meters, both installed by the power company and you're not supposed to touch any of that. Of course, people snip off the little plastic tabs all the time, and the power company doesn't seem to care much, as long as you haven't upped your supply current in the main breaker without telling them so they can bill you for the higher service. This is all the responsibility of the power co, and it's installed in a box on the outside of the house.

Anyway, there is no ground-neutral bond at the main breaker/meter either. Also, our main breaker/meter at the house here has no ground - just 3 phases + neutral. I was peaking over the power co's tech when he replaced our main breaker a few years ago. It's all pretty simple.

But back to the Farm... The solar panels seem to feed power back onto the grid at the point where the power co's cabling comes in to feed the main breaker and meter for the house. All the wiring for this is concealed, so it'll prolly be impossible to check any of that thoroughly.

I thought the solar system was separate and tied to its own circuits - if its integrated with the house grid, then all the local codes apply - whatever they are.

A ground at the transformer is good if its not too far away.

I haven't worked with grid-tied systems and I don't recommend them for most folks needs. If the inverter is noisy (most are), then this noise gets back on the grid.

 

[LQB]

Here they do stuff a bit differently. You never bond neutral-ground at the panel. The neutral at the local transformer is grounded, and it's strictly verboten to bond neutral to the local panel ground in an installation. They also are rather emphatic about not bonding ground to water pipes and that kind of thing.

Same here on the water pipes but the neutral grounding is certainly different.

 

[LQB]

Milham (see recent Sott article: http://www.sott.net/article/296453-EMF-Pollution-Man-Made-EMF-Dirty-Power-and-AC-magnetic-fields#) maintains that transients on the grid (resulting in high frequency noise) are as old as the grid itself - but in recent decades has gotten much worse due to high-tech explosion.

One explosion would be the massive increase in grid-tied solar systems. These systems use solid state semi-conductors (FETs) to approximate the 50/60 Hz grid sinusoids which are phase-matched to the local grid. Compare this to a massive steam-driven turbine at a power plant. The turbine is basically a carefully controlled analog generator that outputs a very clean sinusoid. In comparison, the solid state inverter (DC to AC) is a dirty replica of this sinusoid - and if added to the grid, the high frequency noise goes with it. So, the more grid-tied solar systems, the more high frequency noise on the grid.

At the end above article Good Optics commenter says:

... The guys on the truck went up the pole to find three of the seven bare -aluminum- conductors in the common return were broken, just fatigued from 50 years in the weather, and how the -hell- did I know that ? ?

So I told them: colour CRTs are very sensitive to external magnetic fields because unlike monochrome CRTs they have to very accurately converge three electron beams, at different relative strengths, onto specific parts of the screen to produce a specific R(ed), G(reen), B(lue) color.

The field that was causing my troubles was a least nine feet away from a magnetically shielded monitor and was caused the 60Hz magnetic field generated by an unbalanced (not self-cancelled by an equal return) current flow of only a few amps.

Most electricians have no clue . . .

These broken or loose connections can cause arcing transients that greatly increase the high frequency noise on the grid. How many homes are now contributing to this noise (due to aging infrastructure)?

Another big source of noise is the explosion of digital electronics that require DC power - so AC must be concerted to DC (digitally) resulting in more high frequency noise. Cell towers (and their masses of digital electronics) are ubiquitous and their contribution to grid noise continues to rise.

I'm sure there are many other sources on the rise, but these are some biggies.

 

[LQB]

From Powerwatch: http://www.powerwatch.org.uk/news/2015-06-28-science-update.asp

Gandhi G et al, (July 2014) A cross-sectional case control study on genetic damage in individuals residing in the vicinity of a mobile phone base station, Electromagn Biol Med. 2014 Jul 9:1-11. [Epub ahead of print] [View Author's abstract conclusions] [View on Pubmed]


Mobile phone base stations facilitate good communication, but the continuously emitting radiations from these stations have raised health concerns. Hence in this study, genetic damage using the single cell gel electrophoresis (comet) assay was assessed in peripheral blood leukocytes of individuals residing in the vicinity of a mobile phone base station and comparing it to that in healthy controls. The power density in the area within 300?m from the base station exceeded the permissive limits and was significantly (p = 0.000) higher compared to the area from where control samples were collected. The study participants comprised 63 persons with residences near a mobile phone tower, and 28 healthy controls matched for gender, age, alcohol drinking and occupational sub-groups. Genetic damage parameters of DNA migration length, damage frequency (DF) and damage index were significantly (p = 0.000) elevated in the sample group compared to respective values in healthy controls. The female residents (n = 25) of the sample group had significantly (p = 0.004) elevated DF than the male residents (n = 38). The linear regression analysis further revealed daily mobile phone usage, location of residence and power density as significant predictors of genetic damage. The genetic damage evident in the participants of this study needs to be addressed against future disease-risk, which in addition to neurodegenerative disorders, may lead to cancer.

 

[3DStudent]

I wanted to post this a few months ago, when the EMF podcast aired. A few weeks after that podcast, and maybe because it was on my mind, I became aware of a lot more cell towers. It was almost as if they, like weeds, popped up overnight. And some I am pretty sure weren't there within the past 6 months. And one day I took a different way home, but on the same road but the opposite side, and I saw a tower I normally would not see on the normal side of that road.

So I started having kind of "What the.." thoughts about them. I suppose I could have just not payed attention and become more aware after the podcast. But just wondering, has anyone noticed cell towers just kind of pop up everywhere in a short period of time?

One other thing: I recall in the EMF podcast that mention of one of those ionizing wristbands. I looked some of them up and it looks like the Infinity Pro is a good one, with a large negative ion output. It's made from tourmaline. Here's a video of it being measured. Anyone use these or know of a better brand? Thanks.

 

[monotonic]

I noticed cell towers appearing everywhere years ago, even some fake tree towers. Now there don't seem to be many new ones popping up. I think mobile companies tend to pick areas and then "colonize" them. It could just be it was your turn. But yeah, it was a bit freaky and surreal, when I had just started learning about the dangers of EM radiation.

 

[MusicMan]

The proliferation of cell towers is proceeding apace, even in Australia. The fake tree cell towers might just be the tip of this iceberg.

I think you need a decent spectrum analyzer to determine which frequencies need to be suppressed. Obviously you don't want to suppress the mains frequency (50Hz/60Hz).

A good way of suppressing spurious frequencies is with notch filters, one for each of the spurious ones, and in-line with the current. These can be tunable.

If you are operating multi-phase systems you would need a set of filters for each phase, as each phase might be carrying different spurious frequencies.

Radiation from cabling could be eliminated partially by using twisted cabling.
I like the idea of using ferrites around the cables to absorb transient spikes.

A common earthing point would be desirable, to eliminate earth loops which can act like antennas.

I would paint the entire room and ceiling adjacent to your equipment panels with a good conductive paint surface which is then earthed via the common earth.
Your panel itelf should be in an earthed metal box not a wooden one.

And silk clothing for those working / living in the vicinity.

I'm not an engineer, but I've had a lifetime in electronics, and repaired test equipment among other things for Siemens. Over here all the equipment I worked with used 50Hz at 240V.
Most people would not be aware that transients on electrical lines can spike up to over 10,000 volts, just from switching on a transformer. I like the idea of using a very high voltage, low capacitance (a few picofarads) capacitor to take these transients to earth.

Telco's use neon tubes to protect lines against lightning and other switching spikes, with two neon filled spike absorbers across the line, one rated at 90Volts, and another rated at 600Volts. The neon will flash if the voltage is exceeded, grounding the spike. This is only suitable for phone/data lines though, as mains voltage is too high.

FWIW

 

[theos]

One other thing: I recall in the EMF podcast that mention of one of those ionizing wristbands. I looked some of them up and it looks like the Infinity Pro is a good one, with a large negative ion output. It's made from tourmaline. Here's a video of it being measured. Anyone use these or know of a better brand? Thanks.

I ordered one of these. If I'm not mistaken Gaby may have one too . I don't have it yet but I can report back. EDIT: I forgot to add that I found a 20% off coupon code for it, in case anyone is interested.

The horror of the situation regarding EMF seems to be growing worse for me. I'm in the middle of reading the book Electromagnetism and Life by Robert O. Becker (author of The Body Electric). He lists study after study on the biologic effects of EMF. It's not pretty. It's like we live in a microwaved world

 

[Gaby]

I ordered one of these. If I'm not mistaken Gaby may have one too . I don't have it yet but I can report back.

I have one, yes. It is here next to me :P

I don't know if it works. When I'm wearing it, I might be more conscious about all the EMF pollution, hence more self-aware? I do feel more re-assured with that thing around though.

 

[Jacques]

One other thing: I recall in the EMF podcast that mention of one of those ionizing wristbands. I looked some of them up and it looks like the Infinity Pro is a good one, with a large negative ion output. It's made from tourmaline. Here's a video of it being measured. Anyone use these or know of a better brand? Thanks.

I ordered one of these.

And I have one of these: http://shop.safeconnectplus.com/BodyBand_Plus_s/1913.htm

And for the home: http://shop.safeconnectplus.com/House_Shields_s/1915.htm

 

[Zadius Sky]

The horror of the situation regarding EMF seems to be growing worse for me. I'm in the middle of reading the book Electromagnetism and Life by Robert O. Becker (author of The Body Electric). He lists study after study on the biologic effects of EMF. It's not pretty. It's like we live in a microwaved world

Thanks for that book - I just got it from the library and now reading it.

I'm constantly around the towers and wifi both at my apartment and work. My new office is now above the laboratory, where they are experimenting new frequencies for new wifi devices, giving me headaches. I was in a meeting a few weeks ago, where a new project is in process of installing 105 wifi devices at the football stadium and a new cell tower being built near there. All for convenience and cost-effective. It's crazy.

I'm definitely getting the wristbands.

 

[monotonic]

I think you need a decent spectrum analyzer to determine which frequencies need to be suppressed.

We can't predict everything that will happen on the mains, so making a very specialized filter for the interference you see on one day will be time consuming and may not even be very effective.

A good way of suppressing spurious frequencies is with notch filters, one for each of the spurious ones, and in-line with the current. These can be tunable.

A great deal of the noise is not single frequencies, but a spray of harmonics from sharp and jagged signals. A single notch filter wouldn't do much good. A transmission line could be cut to resonate at all the right frequencies, if the wavelength is low enough, because the cable will need to be short enough to be manageable. But this would need to be done on a per-appliance basis, and the great majority of the radiation probably comes from the antennas anyways, not the house wiring.

Radiation from cabling could be eliminated partially by using twisted cabling.
I like the idea of using ferrites around the cables to absorb transient spikes.

Twisting wires can greatly reduce the radiated field. Ethernet cable has very precise twisting to achieve the best noise rejection and minimize crosstalk between the signal lines. Ferrites however usually only work at VHF and stop working at high currents due to magnetic saturation of the ferrite core, unless you know how to find a heavy-duty one.

A common earthing point would be desirable, to eliminate earth loops which can act like antennas.

As long as all the power conductors including ground are kept with each other and not separated, then the loops are minimized. Separating the ground wires to make a star at the junction box would actually make an enormous current loop between ground and the other two conductors. However appliances connected via signal connectors can form ground loops which can be improved with ferrites on the signal lines.

I would paint the entire room and ceiling adjacent to your equipment panels with a good conductive paint surface which is then earthed via the common earth.

This is a static shield, but the room by the junction box won't necessarily have a much stronger EMF field. I would say measure first, then determine your needs.

Most people would not be aware that transients on electrical lines can spike up to over 10,000 volts, just from switching on a transformer. I like the idea of using a very high voltage, low capacitance (a few picofarads) capacitor to take these transients to earth.

If you think about it the mains wiring is one long capacitor amounting to hundreds or even thousands of pF (wires being the plates and insulation being the dielectric). The line itself also forms a spark gap which I'm guessing is why the spikes don't tend to go over a certain voltage.

Telco's use neon tubes to protect lines against lightning and other switching spikes, with two neon filled spike absorbers across the line, one rated at 90Volts, and another rated at 600Volts. The neon will flash if the voltage is exceeded, grounding the spike. This is only suitable for phone/data lines though, as mains voltage is too high.

Most transient suppression devices (MOTs, GDTs, etc.) are consumed over time simply because of the enormous amount of power they have to suppress, making it difficult to make one that can last indefinitely. Fortunately the electrical standards seem good enough that the vast majority of appliances can handle the average grid noise condition.

 

[LQB]

I ordered one of these. If I'm not mistaken Gaby may have one too . I don't have it yet but I can report back.

I have one, yes. It is here next to me :P

I don't know if it works. When I'm wearing it, I might be more conscious about all the EMF pollution, hence more self-aware? I do feel more re-assured with that thing around though.

As I said in the Sott H&W interview, the q-link is the only device I've seen where double blind study showed clear benefit in RBC clumping - and disabled q-links were also used (and failed).

The device uses passive crystal oscillators connected to 75 feet of gold wire in order to resonate at Shumann frequencies (alpha for example). The theory is that the resonance supports the user's bio-field thereby reducing the impact of EMF - it does not shield EMF/RF. Beverly Rubic was involved in conduction the original study that used RBC clumping as a measure of effectiveness.

Exact quantitative mechanism is unknown - afaik.