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Magnetic Field Trouble

  1. Nov 7, 2006 #1
    I am in real trouble here in Los Angeles.
    My computers and phone system are going down intermittently and it is literally crippling my business with 60 full time employees. We have tried everything! The local Dept. of Water and Power might be the problem. My building is within 100ft of a major power line coming into L.A. and I have been told that it is possible that magnetic fields coming from that power line could be responsible for equipment failures, including a very sophisticated online battery back up. Is this possible? And if so, how can I prove it to them so that I can get them to act on it? HELP PLEASE!!!
    Last edited: Nov 7, 2006
  2. jcsd
  3. Nov 7, 2006 #2
    I'm not sure how technically competent you are so forgive me if I sound like I'm teaching my Grandmother to suck eggs in the following paragraphs:

    Large currents flowing in cables, such as power cables create very large magnetic fields around them. This is something which has been established for well over 100 years, and probably a good deal more than that.

    Even small currents passing through wires do this. This is how relays work. The current flows through the coil and creates a magnetic field which attracts the contact and closes the switch.

    Electric motors also work on this principle. Without electric currents producing magnetic fields most of the things modern technology relies on for it's power simply would not work. It's one of the most fundamental principles of physics.

    Bear in mind that it will be the power companies policy to say that it is impossible the first few times to see how persistant you are. Bear in mind they probably get so many cranks ringing them up blaming them for all kinds of stuff they're not responsible for. Your best bet is to just perservere.

    So to answer your question directly...

    ....yes I think it is possible. It might be causing unwanted voltages to occur and currents to flow which are upsetting the way your equipment works. I suppose if your battery back-ups are relying on electronic equipment to turn them on it could be particularly problematic given that electronic equipment uses low currents and voltages and would thus be the most vulnerable to such things.

    I must ask though if your equipment is suitably protected? In my days as a panel wirer we wouldn't dream of running sensitive data cables in anything other than screened cable which carriers unwanted electric currents straight to ground. Also anything which was encasing electronics was also earthed to the panel's body which was in turn connected to earth at the installation location.

    Perhaps it is a combination of both factors?

    I hope that helps a little bit, but bear in mind I represent the novice end of the spectrum on forums as sophisticated as these and there are others who could give you a much better and more detailed answer :wink:
  4. Nov 7, 2006 #3
    Thank you so much for your reply. Any information at this point is helpful. I am happy to know that it is in fact possible for magnetic fields to cause our problems. I will now give you some more info.

    We have attempted to increase the grounding of all possible problem areas. The result was a bit disappointing. We actually suffered more events!

    Is it possible that there could be current running in the ground? We noticed that some of our conduits had current!

    Our T1 telephone line is also suspect because it runs through the entire building and pretty much connects to everything including the computers. Can you recommend any additional shielding for telephone lines? The cost of going fiber optic on a 600ft run from the street to the phone room is prohibitive.

    I just heard today that circuit breakers are now tripping on the U.P.S. and the main electrical panel. It was suggested to set up a fuse panel rather than breakers for the computer and phone equipment, and not use the online U.P.S. temporarily because it has a built in circuit protection that keeps tripping.

    Any other thoughts or suggestions?
    Last edited: Nov 7, 2006
  5. Nov 7, 2006 #4


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    Are your business neighbors having the same problems? Did the previous resident in your building before you moved in have the same problems?
  6. Nov 7, 2006 #5


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    Just a suggestion, but do you have a compass? If you take it just outside your building and it points to the power main instead of pointing North, then there's a good chance that the main is indeed the source of your woes.

    Out of curiosity; are the walls of your building cement, wood, or metal?
  7. Nov 7, 2006 #6
    Great Question!
    The building is only about 5 yrs old and the previous owner says he did not have any problems. I wonder if he is trying to cover his butt though because if he did have problems and did not disclose them in the sale, he has some legal liability issues.

    The building is in a newly developed area so there is no history prior to this development. The nearest company is next door to us, separated by a concrete shear wall and drywall partition combination that runs about 100ft front to back.
    They are west of our side which is west of the power line so we are closer to the problem.

    Unfortunately this company has almost no computers or phone equipment, only the bare minimum, as it is a storage company with one small office. They have reported no problems.

    The next closest building is about 500ft from the power lines. They have a full office with phones and computers. They have reported no problems. So far, we have not found anyone in the immediate area that is having the same problems we are suffering.

    We went virtually trouble free for our first year or so, but dropped calls started about 4 months ago and got progressively worse to the point were for the last few weeks it has been a nightmare.

    I had someone research that power line, and there appears to have been some increase in usage or power fed through it that coincides with our increasing problems.

    The power company is not helping us. They keep saying that their tests show power at the street and anything inside of that is our problem.

    Thank you for your question.
  8. Nov 7, 2006 #7
    The building is 125,000 sf, tilt up, steel reinforced concrete which is partitioned, my company using 80,000sf and the storage company in 45,000sf.
    Last edited: Nov 8, 2006
  9. Nov 7, 2006 #8
    I don't know what your business is but you must either have some INCREDIBLY sensitive equipment or you are so close to the transmission wires that you can read the manufacturer off the jacket.
    for a field to be strong enough to effect most common computer systems and UPSs (both are usually shield grounded) you would almost have to be able to feel it on your body like a Van De Graf.
    I think you would be better testing the quality of the power coming into the building then the fields around it. Crappy power w/ brownouts and spikes that are so famous in the CA powergrid could be doing it, a neighboring building on the same transformer leg could be giving you the shiv with equipment surges.

    Just my low tech opinion but I asked my neighbor who is a Domionion Power site engineer and that was his first thought too.
  10. Nov 7, 2006 #9
    Good suggestion. we tried the compass INSIDE the building awhile back with negative results, I believe.

    I just got off the phone with my operations manager and he has arranged for monitoring equipment that will record what we think now might be bursts of strong DC magnetic fields. i think recording is the key here.

    We have had a man named Tom Shawnesey working on this off and on commuting from the San Fransisco area. He is a 30yr so called expert in this field and he has never seen anything like it.

    The equipment is on site now waiting for him to arrive to set it up today.

    Thank you very much for your suggestions.
    Last edited: Nov 8, 2006
  11. Nov 7, 2006 #10
    How can we PROVE this hypothesis?

    The power company has put their monitoring equipment on the main line a few times and claim " no problems ".

    Does anyone else think I'm barking up the wrong tree regarding magnetic fields? We have no ultra sensitive equipment, just standard IBM computers and standard phone equipment.

    We are very close to a MAIN line that serves 45% of the city of Los Angeles and yes, we could come close to reading something written on the tower, but no sign of any physical discomfort.

    Thank you for your input.
    Last edited: Nov 7, 2006
  12. Nov 7, 2006 #11
    Could anyone on this topic get a professor of electrical engineering to read this?

    I can’t stress enough, the devistation this problem is causing my company. As I said before we have nearly exhausted all avenues and have some pretty smart guys scratching their heads on this.

    Is there any way I could contact this dominion power site engineer directly? It sounds like he could help me as well.
  13. Nov 7, 2006 #12
    Buy a spool of wire and hook a meter to the two ends. If there is a large magnetic field won't it generate a current through the wire?? could be fun to watch and you never know maybe you get free power to send back to the company:eek:
    have YOU put a recorder on the line to see it's condition? the power company isn't going to admit it's bad because if they do they are also admitting to fault in your equipment loss..and a financial liability.

    I'll send him (my neighbor) this link and let him decide.

    Why I'm so against the theory is from watching the area around our LORAN transmitting towers, they change the growth pattern of the fields around them yet our laptops work fine at the base (but we can't spend more then 15 min on field while they are activeby regs)
    Last edited: Nov 7, 2006
  14. Nov 7, 2006 #13
    The spool and wire test may be what they are doing today with more sophisticated measuring and recording devices.

    Can you suggest the type of monitoring and recording device we could use at the street? Would this device be illegal? Would we have to disconnect three 480v hot lines to attach it? Don't you think their liability would be even greater if there was some conspiracy to try to hide these problems from us?

    I am just a business man with a little bit of logic and common sense, so I don't really know what your LORAN towers are, but if they generate large magnetic fields and you can't stay on for more than 15min. that may be a good argument for the m.f. theory.

    Thanks for sticking with me here.
  15. Nov 7, 2006 #14


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    This is way outside of my area, so I'm just tossing an idea. If no one else is having the difficulty, is it possible that there's an underground conductor such as a steel culvert that might be picking up the field right under the line and transmitting it to your location? I don't even know for sure if that's physically possible.
  16. Nov 7, 2006 #15
    I forgot to mention.

    We have also tried 2 different generators, one permanent, on site, and one portable trailer mounted. Amazingly, even THAT has not stopped these events from happening, and these were wired to a very expensive online battery back up that we rented.

    Early on, we tried to meter what was happening inside our server and phone room and we saw voltage drops on the meters monitor during these events. Later we found out that the meters were being effected by the event which rendered them totally useless.

    Our expert had to bring in some heavy low tech old metering devices to get any decent info, i'm not sure if they were any help.

    We have done so much that it is hard to remember everything in one post.
    Last edited: Nov 7, 2006
  17. Nov 7, 2006 #16
    Good question!

    Yes, there is a culvert BETWEEN our building and the power line, about half the distance but parallel to the lines and not crossing the lines or our building. It is partially above ground concrete and transitions underground as it gets closer to the street.

    So I don't think that would be an issue.

    Thanks for your input
  18. Nov 7, 2006 #17


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    You're probably right about it not being an issue, particularly since it's concrete, but... does it happen to contain rebar?
  19. Nov 7, 2006 #18
    Since the culvert is relatively new, it might have a small amount of rebar in it.
  20. Nov 7, 2006 #19


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    Again, since I have absolutely no idea what I'm talking about, this is probably wrong. I'm just wondering if any such rebar might, because of its pattern within the culvert, be acting as an antenna to direct the field your way.
    Somebody else better get back into this, 'cause I'm way over my head.

    Since nothing else seems to be going on right now, I'm going to bugger off and play a game or two. I'll check back in a bit.
    Last edited: Nov 7, 2006
  21. Nov 7, 2006 #20


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    I would try shielding the computers, perhaps turn your entire office into a big faraday cage?

    You could try shielding just one computer to see what happens first, and go from there perhaps... Are your computers randomly restarting, or is something else happening? Are your UPS power supplies voltage regulators as well? Have you tried monitoring what the power looks like on your wall outlets, looking for spikes or irregularities?

    You might consider contacting a local university to see if any professors would be interested in investigating, perhaps for a nominal fee.

    Here's some reading for you, a good experiment might be to try shielding a single computer and UPS, to see if you are able to shield it from any problems...
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