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Comment: Re:Makes sense. (Score 5, Informative) 168

by effigiate (#39357633) Attached to: AC and DC Battle For Data Center Efficiency Crown
One of the challenges of HVDC, especially in the transmission/distribution world, is that normal switching happens on the line and not at the breaker. If you can switch futher down the line, you can leave all the people closer to the breaker with power. The issue is that this switching happens while current is flowing which requires that the device interrupts real current. In the AC system this is relatively easy because the arc created by opening a high voltage circuit under load goes out at every current zero. There is no current zero on DC, so you force the interrupting device to break current. An similar situation can be seen if you look at relay contacts. They may be rated at 20A @120VAC but only 0.5A at 12VDC.

Comment: Re:"Clocks" (Score 1) 439

by effigiate (#36563084) Attached to: Power Grid Change May Disrupt Clocks
Large metropolitan areas know this very, very well. Making sure that the phase angle on both sides of the open disconnect switch you plan to close is essential. Because of the high population density, the current generation must be very close to the customer. The closer you are to the generation, the more current is available. Even a few degrees off can push tremendous currents (40kA+) without any kind of phase to ground fault or phase to phase fault. Substation protection engineers have specialized equipment for just this purpose.

Comment: Great for two players, what about the viewers? (Score 1) 157

by effigiate (#36375918) Attached to: Sony's Solution To Split-Screen Multiplayer
Like many have said, I think this is a great idea. One of the things I dislike about multiplayer on the same console is the amount of screen you lose. This would be great for two vs. two as well; both players on one team can only see their teammate's screen and not their opponent's screen.
The downside to this is you can't have people watch you play. They're either going to see your screen or their screen, they won't be able to see both. I imagine games that use this technology will have a "traditional" multiplayer for when there are more than two people in the room.
Regular 3D just looks blurry to someone without glasses beacause the two images are pretty similar. What happens when the images are drastically different? It will be impossible to watch.

Comment: Re:Power required to charge? (Score 1) 603

by effigiate (#34062554) Attached to: Electric Car Goes 375 Miles On One 6-Minute Charge
The risk of any large current source (battery, capacitor) is easily mitigated with proper fusing or some other type of current limiting device. I'd be *very* surprised if the charger wasn't already equipped with some method to handle a short circuit, it is something you can almost plan on happening with any battery charging circuit.

Comment: Re:Doesn't explain... (Score 1) 269

by effigiate (#32178066) Attached to: Ball Lightning Caused By Magnetic Hallucinations
I'd be really surprised if that was phase to phase arcing on the power lines. At least in the US, there are protection measures in place that detect phase to phase arcing and will kill the power to the overhead lines. These have been in place for years, I doubt Saudi Arabia doesn't have similar systems in place.

Any sufficiently advanced technology is indistinguishable from magic. -- Arthur C. Clarke