Forgot your password?
typodupeerror

Comment: Re:Is this news? (Score 1) 74

Charged particles are not magnetic. The electric current caused by the electric current creates a magnetic field. Basic electrical magnetic property. There is a magnetic field because there is an electric current traveling through the atmosphere which does impose an electric charge on suspended insulated objects in addition to the induced electric current in conductors on and in the ground.

The amount of induced current is directly related to the rate of flux change producing an AC current provided one end of the conductor is grounded. At the low currents and large area of very long lines, this AC component is relatively low in relation to the DC current brought in at the poles seperated by our earth's magnetic field. A static magnetic field does not induce a current. A steady DC current does build high currents in long suspended conductors.

http://en.wikipedia.org/wiki/E...

Even high voltage transmission lines are now protected by adding a resistor to the center tap of a 3 phase transformer to ground to limit induced current. The transformers already MUST have a ground refrence already due to the DC charging of the lines that would happen if there were no ground. This is why transmission lines never use Delta transformer to Delta transformer. One or both ends of a transmission line have a substation with a Y connection with the center tap grounded.

I know of one BPA line that is Delta to Delta, but in addition to this there is a 3 phase Y transformer to nowhere that only porvides the required ground for the line.

Grounding both ends with a low impedance ground is good for lightning strike protection, but bad in a geomagnetic storm. Ungrounded is bad for line charging and lightning protection. UTP network cable is ungrounded at both ends and are subject to high voltage charging in short lengths.
http://www.solarsystemcentral....

Comment: Re:Buy Surge Protectors (Score 1) 74

Well most "country" wiring I've experienced has multiple problems. Mostly from old, unmaintained wiring and transformers but it sounds like you've got enough of that already. While most storms will cause havoc, just the utility not giving a shit will probably cause most of the failures inside a home.

Comment: Who keeps track? (Score 1) 212

by Wycliffe (#47436049) Attached to: My most recent energy-saving bulbs last ...

My house is a mix of CFL and tungsten with a few halogen and leds thrown in. I replace a half dozen tungsten a year and
over the years I've had to replace the occasional CFL but I honestly couldn't tell you if the CFL I replaced was 1 year,
2 years, or 5 years old. I can say that I have to replace tungsten more often and as my house is a fairly even mix then
I would guess that the CFLs last 3-4 times longer but I don't keep track of how old my bulbs are.

Comment: Re:I have automated maintenances in the form of .. (Score 1) 240

by Wycliffe (#47435681) Attached to: Ask Slashdot: Unattended Maintenance Windows?

I am updating your outward facing mail server, the update fails, where is your god/email now?

If at least some part of your paging and monitoring system isn't independent from your servers then you're doing it wrong.
We use multiple third party companies to monitor our website. It's highlevel checks but one of the checks is to check
that our internal monitoring software is working. You can purchase third party monitoring software or spin up an instance
somewhere like amazon or digital ocean for a few dollars a month. Depending on how critical your systems are you
could spin up a few dozen. The point is that you should be monitoring your servers from outside your network for
multiple reasons. The first being that it doesn't really matter if everything is up if the outside world can't connect to it
and the second being that you still want to be paged if your entire datacenter goes up in smoke.

Comment: Re:Is this news? (Score 2) 74

The elevated lines between buildings are rarely protected from a build up of a static charge as routers and bridges were not built with this in mind. On the physical layer, both ends of the wire are terminated into an isolation transformer with no discharge path to ground. This is an installation design fault against the guy that designed the installation. Lightning protection is often a gas discharge tube for a lower breakdown voltage. A high current discharge through a protection device can produce a relatively high ESD pulse through the transformer into the tranciever chip resulting in corrupt data to failures. A link between buildings must include a bleed discharge path to prevent the build up of voltage on the wire, or a shielded wire with grounded shield should be used.

Engineers design systems. A good technician can make them work.

Comment: Time to apply science (Score 4, Informative) 74

Time to apply science to the problem. What is known, what values are involved, and what breaks down.

Long distance transmission lines have two problems when there is a relatively high atmospheric current. They are long conductors feeding transformers that are not designed to shunt large components of DC resulting in core saturation and high current. This is measurable. The first effect noticed was by the railroad when telegraph relays activated and sometimes burned out.

The voltage induced current has two components. 1 Some current was due to the current directly into the long wire. 2 Some current was due to ground potential changing due to high current in the ground.

How to protect? For ground potential issues, simple pairs of wires provide high common mode rejection. This is common with telephone circuits as protection from induced hum and noise from a noisy electrical environment. Overvoltage protection in the form of lightning arresters is the second protection. Most phone loops are relatively short reducing the ground voltage gradient problem to non existant levels. Long distance hops are by Microwave Relay or Fiber Optic, both providing protection from ground gradients and long pick up paths.

Shrink the scale to inside a home by comparison. All internal house wireing is orders of magnatude shorter than transmission lines, CATV, and phone lines. Small DC capible antennas result in very low current if exposed. The home is generally protected by gutters on the eves, mildly conductive building materials such as wood, brick, etc that are not insulated to very low leakage at high voltages such as the insulatin on transmission lines. Net result is the very small currents are shunted by the building itself. Go up on the roof during a geo storm and see if you have any static electricity issues. Probably not.

For homeowners, this is a non issue due to the lack of an effective gathering surface properly insulated to collect enough current to cause any damage. The collector is too small and the leakage path to ground is too high.

Comment: Buy Surge Protectors (Score 3, Interesting) 74

If you haven't already bought them, buy surge protectors. After replacing the fourth dishwasher in our less than 8 year old house due to circuitry issues we installed a whole house surge protector. They work and it doesn't take a magnetic storm to cause issues, most of the grid delivery is +/- 15% on voltage just in my area normally.

Comment: Re:Orwellian (Score 1) 104

by Virtucon (#47431237) Attached to: Google's Experimental Newsroom Avoids Negative Headlines

Meet the new media control overlords. It used to be we had filters like News Editors, TV Anchors etc. who had a set of principles and presented the news based on those principles. Of course individuals like William Randolph Hurst realized how powerful this was and fashioned and tailored the news to their own agendas. This gave their already immense power even more capabilities to shape the dialog and issues of the day. Google, Huffington Post et al. are all in the same business and both actually don't generate actual news content but merely serve as spin doctors pushing the issues to their suited direction. We shouldn't be surprised that Google is trying to influence our opinions, it's been done for hundreds of years and although the media distribution may have changed controlling public opinion is an old game.

Comment: Re:I hate to imagine it (Score 1) 119

by Wycliffe (#47431215) Attached to: Child Thought To Be Cured of HIV Relapses, Tests Positive Again

The Washington Post story states:

Researchers confirmed through DNA sequencing that the infection in the child is not a new infection, but was the one passed from the mother.

If the reinfection is also from the mother (which is what is most likely) then how can they tell whether it is the original infection or a reinfection
from the mother as presumably it's still the same strain in the mother.

If you had better tools, you could more effectively demonstrate your total incompetence.

Working...