Engineering

VAC – A New Beginning

Well, my old nemesis ComEd has reared its head again. Last night, I had another beep hunt. This was a steady, rapid beep, so it only took about 30 seconds to find the problem: The alarm was going off on the UPS protecting the television and TiVo. It’s a fairly dumb UPS, so there’s no […]

Fukushima: Waiting For the Magic Bullet

Here’s something I’m wondering about. Maybe some of you can help me out, or point out where I’m going wrong… The situation at the Fukushima Daiichi plant is just continuing to deteriorate, with damage at all three fueled reactors, containment cracks at two of them, and overheating spent fuel pools at one of the shutdown reactors, […]

Fukushima Uncerntainty

A lot of people have been saying a lot of things about the nuclear emergency in Japan, much of it conflicting, and therefore much of it wrong. I see no reason why I shouldn’t get involved. As with almost everything else I talk about here, I claim no expertise beyond an amateur interest in the […]

Elevator of Death…Or Not

When it comes to elevators, our biggest fear is that the cable will snap and the elevator will fall to the bottom of the shaft. People debate whether there is anything you can do to save yourself—jumping just before you hit is the most popular suggestion. A few years ago, Mythbusters did a test, and the result […]

The Mystery of the Self-Unscrewing Bulb

Libby asks: How do light bulbs unscrew themselves? This can’t be only be happening to me. My lamps are really old and rickety for the most part but I don’t think that’s the reason that I have to retighten the bulbs every once in while. Sometimes I think the bulb is out and discover it’s […]

NYT Animates the Cory Lidle Crash

The New York Times has a Flash illustration of Cory Lidle’s plane crash that is just a terrific example of how to use computerized media to explain a news story. Check it out.

Son of VAC

Well, I thought my electrical problems were over. About five minutes ago, however, the lights went out. Looking out the windows, I can see that the lights are out in several neighboring blocks as well. I can still see skyglow, and some lights further away, so it’s not the whole city. (4 minutes to shutdown.) […]

VAC, The Final Chapter

(Links to Chapter 1, Chapter 2, and Chapter 3.) When I first called ComEd’s customer service center to complain about the electricity in my house, I wasn’t even sure that 135 volts AC was out of the accepted range for electric service. While several consumer web sites have information about electricity costs and rules for […]

VAC, Part 3

I did some more exploration of the local electrical power situation I outlined in my previous two postings. (Part 1 and Part 2.) I drove to another block fed by a different phase of the same three-phase distribution lines that feed my building. After a couple of times around the block, I spotted an apartment […]

VAC, Part 2

As I mentioned in my last entry, we’re having a few electrical problems at our house. ComEd is supposed to supply voltage at 120VAC (Volts Alternating Current). That’s just a nominal value, it can vary a bit. ANSI standards supposedly permit 5% variation, from 114 volts to 126 volts. ComEd’s rule book says they may […]

VAC

Here’s a question that’s turning out to be harder to answer than I would have thought: What’s the acceptable voltage range for your house? A few days ago the lights flickered and the speakers on one of my computers started making funny noises. Turns out they’re fried. That computer system wasn’t on a UPS, so […]