[RE-wrenches] Inverter causing migraine?

[Dan Fink]

Joel --
Good points. In a recent newspaper article in Boulder, CO about a really 
bad PV install, the direct grid tie inverter was mounted right on the 
outside of the wall from the homeowner's bed. They finally had to have 
it moved--mostly because of buzzing, but EMF was a concern too. It was 
basically less than a foot from the guy's pillow.

Also, I forgot to mention that there are fairly inexpensive EMF meters 
available from the same places that sell DIY shielding materials.

The biggest source of EMF at *my* house is actually the E-Meter 
measuring amp-hours. It even interferes with my handheld ham and fire 
department radio FM communications on 2 meter.

DAN FINK
Renewable Energy Consultant




Joel Davidson wrote:
> Ron,
> 
> Electromagnetic fields are produced any time you have current flowing 
> through wire. They are low frequency waves that drop off rapidly 
> proportional to the distance from the source. Inverters, transformers, 
> fluorescent light ballasts, motors, clock radios, power blocks, 
> microwave ovens, kilowatt hour meters, service panels all emit EMF. 
> There is no
> practical way to block EMF.  It passes through almost everything 
> including walls and even lead. There is no U.S. safety standard for EMF. 
> Some say 8 milligauss or more is dangerous and 2.5 milligauss or less is 
> safe.
> 
> I went through our home about 10 years ago using a borrowed milligauss 
> meter (thanks David Katz). Our utility meter service had significant 
> EMF, but that was not a problem since it is mounted on an outside wall 
> and there is a closet between the living space and the meter. The EMF 
> had fallen to below 2 milligauss between the wall and the closet door. 
> The bedroom clock radio was the second largest EMF source in our home. 
> Moving the clock 1 foot away from the bed to the other side of the night 
> stand brought the EMF levels under 2 milligauss. Our SW4048 inverter 
> emitted a field that fell to a safe level 2 feet from the inverter.
> 
> I tell people not to put their bed against the wall where their utility 
> service panel or inverter is mounted. I also tell them that the Japanese 
> did a 2 year study of school children riding the Tokyo subway (big EMF 
> emitter) and found that there was no danger.
> 
> Some sounds that most of us take for granted can cause physical 
> discomfort and even pain. SW4048 and other transformer and electrical 
> and electronic buzzing can be annoying. Also certain wavelengths and 
> intensities of light can cause pain and injury.
> 
> Joel Davidson