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Comment Re: Emergency Brake? (Score 1) 564

Oh. I want to add:

I know these things not because I think I'm a better driver than everyone else (studies show: everyone else also thinks they are a better driver). I learned them because my Dad taught them to me eons ago in a fairly narrow wintry parking lot with the family's new, not-at-all paid for vehicle.

Properly driving on ice/snow/(special simulating oil in warm climates?) should be required training, because it teaches basic vehicle dynamics in a way that can never be normally experienced in a real car on city streets, except in emergencies.

And emergencies are no time to learn, but instead are a time to react instinctively.

"OK, adolf. Visualize some marks for yourself way over there, and remember where they are. Now get going smoothly as fast as you can (getting moving at all was lesson 1), and then immediately turn the wheel and tap the brake. Yeah, you're sideways. Remember those marks you set for yourself earlier? Hit them. And then recover, and neatly park right where you started so you can do it again. Try not to hit the curb."

[Try, fail.]

"But dad, I can't."

[Dad demonstrates the maneuver very sideways, but handily.]

"You cheated, Dad."

Dad: "It's not cheating if it works."

Not everyone has that Dad. Everyone should, but that's impossible. These things need taught somewhere, by someone, though: We wouldn't have any more Toyota debacles if emergency driving were taught alongside casual driving, though we might have a lot more hooning around corners in relative safety...

(Yeah, the topic is the parking / "emergency" brake. My dad taught me about that, too. I'm a grown-ass man (UID checks out), now, but perhaps it should go without saying that my Dad was driving the S-15 and I was working the parking brake in the Safari to stop both vehicles. I already knew how to do this, calmly and successfully, from lessons decades ago, though I've only rarely had to put it into practice.

Learning vehicle dynamics sets the wheels in motion, though, for doing proper emergency braking -- which should also be taught, for those who are slow learners.

And every. fucking. time. when I had my temps and something went wrong, he was like "adolf, #21054, think about what went wrong back there and how you could've done it better." At first, I had no clue, and had to ask for the answer -- which was provided. Eventually, it became second nature to ask myself what I did wrong automatically, analyze it, and answer myself. And eventually the moves became instinctive and automatic. Two weeks after I got my license, teenager-me was thus trusted to go traverse the US solo to hook up with his out-of-state girlfriend, because he (Dad) -knew- I had this stuff down.)

(I still can't parallel park for fuck, though. Dad never taught me that, and the licensed driver's ed instructor was too micromanaging for me to learn anything. It's only been a couple of decades...)

Comment Re: Emergency Brake? (Score 1) 564

Yeah, speeds were moderate -- maybe 45 at tops. (Which might be worse than 55 with a single vehicle, with inverse-square law applied, but I don't feel like mathing right now)

And of course I was gentle on it. In an emergency, including when the master cylinder fails in a two-vehicle towing exercise, one should always be gentle with everything. And it was hard work actuating that parking brake pedal, and my knee (which isn't in the best of shape to begin with) was very sore and weak for days. But I was stopping over and over again, not just once: My knee would've noticed that I stopped once but I'd have been able to walk normally if I only had to stop both heavy vehicles once. These repeated stops properly hurt my body, but I still got it done.

And that's the truth. On with the wild conjecture:

If a single vehicle's engine were in runaway mode (which is ridiculously unlikely with a gas-fired thing with a Bowden cable instead of a linkage, unlike any diesel or (some) FBW Toyotas), the last thing I'd do is use a parking / "emergency" brake -- the first thing I'd try to do is disable the engine, and failing that try to disengage the transmission, and failing that I'd use the hydraulic service brakes -- gently but astutely, and only once. Wherever the car stops is wherever the car stops.

This will never happen with a real manual transmission that includes a manual clutch, because you can always disengage a manual transmission both the clutch and the shift linkage fail simultaneously.

But to complete this absurd scenario, once stopped, I'll simply hold my foot on the power-assisted brake and take my time figuring out how to kill the engine (on a ridiculously-overpowered car, this might mean that one or both drive wheels are spinning at around torque converter lockup RPM, but the car will still be largely stationary if being somewhat angry and terrifying. And a stubborn and stuck electronic dual-clutch automatic has probably stalled the engine long ago in these failure modes simply by being engaged with the wheels nearly or completely stopped).

Note that I didn't mention the parking brake in the above three paragraphs: It's ridiculously unlikely that the engine runs away (even on a diesel with a catastrophic turbo failure) and cannot be stopped, AND the transmission cannot be disengaged, AND the service brakes fail.

It could happen though, I guess, in this world of a million monkeys and a million typewriters. And if it does happen, you can bet your ass I'm using everything I have, including dragging my foot Fred Flintstone style. The parking / "emergency" brake might not be able to completely overcome the power of the engine, but it will at least dump some forward speed as heat and lengthen my short life by maybe enough few precious seconds that I can develop a safe crash plan.

I'm using it.

Did I miss anything?

Comment Re:You're doing it wrong... (Score 1) 137

Alright, first I want to thank you for participating. I meant to do this before, but forgot. So often an Ask Slashdot happens, and the asker never interacts at all.

I can tell from your description that what you experienced was a surge from line to neutral.

Here's what's supposed to happen in any "surge protector" in this scenario:

The surge exceeds the breakover voltage of the MOV that is across line and neutral (which it must have, as it was the MOVs turning conductive that generated the heat that melted the housing). This does two things: It attempts to shunt the voltage, and also draws lots of current.

The circuit breaker (ever notice that the power switch on a surge-protected strip usually says On/Reset?) on the power strip is then supposed (via heating, electromagnetics, or both) to detect this excess ("lots") of current, and disconnect one leg of the mains. Once the breaker trips, things are supposed to be fine until reset, and then function normally (though MOVs do age as they get used like this and you should replace/repair the suppressor before absolutely trusting it again).

At least some of these things didn't happen. And sometimes, the MOVs get blown to bits by transient voltage, in which case they can't do anything further to help.

So. As much as I want to, and in fact did, say that a proper mdoern PSU should be reasonably unaffected by a line-to-neutral transient surge, apparently that wasn't the case here: Either its internal protection failed to be effective, or was effective briefly before being overwhelmed by the duration.

It might have sacrificed itself by blowing its own internal fuse: A post-mortem tear down is always a good idea with stuff like this, even if it involves taking it to the alley behind the hotel and paying neighborhood kids to pummel it with cement blocks until it opens. You'll see what's broken/fried/sacrificial, and learn to make better choices next time, and maybe come back and tell us all about it.

That all said: I tender the following three possible off-the-shelf solutions:

1. A Ditek surge suppressor. These are MOV and circuit-breaker based like most, but they advertise having lower breakover voltages than most others and are therefore more sensitive.

2. A Transtector surge suppressor. These are avalanche diode based unlike most, and are advertised to shunt surges earlier, faster and with more current capability than any MOV-based suppressor. They also use circuit breakers instead of fuses.

3. Someone here mentioned, I think, a Belkin design that includes a fuse, which is doubtless also MOV-based. Having a fuse seems low-tech, but fuses are generally -much- faster than circuit breakers and you can tailor the size of the fuse to your expected load, whereas a circuit breaker will always be sized for the maximum ampacity of the entire power strip. You'd want to install the smallest fuse you can get away with (buy a kill-a-watt or other thing that can measure current, too, to be sure). And you'll know if it's too small because it will blow inconveniently and often.

The idea with #3 is that the MOVs shunt the voltage, the fuse blows very quickly (much faster than a breaker), and there is no drama. Fuses are also much simpler and more reliable than $0.50 circuit breakers. Carrying a few extra (or a dozen!) fuses of different values shouldn't be a big deal as they are small and light and often come with appropriate packaging, and if they're AGC fuses (which they probably are) then you can find replacements literally anywhere on the globe.

IIRC, it comes with a 3A fuse. This seems totally appropriate for multinational use of a modern laptop with its 100-200W PSU, along with a small thing or two like a clock and a real cell phone charger.

(I really like #3, having thought this through for a couple of days)

Note, though, that in all cases (and for all countries!) you'll want to buy a 240V suppressor. I stand by and maintain that a global PSU will work with anything even resembling a sine wave at 240 nominal (including occasional BRIEF! surges well beyond that) for eons without episode, and that it was the duration of this particular surge that caused things to go ape-shit, so there is no harm, and zero increased risk to using a 240V suppressor in a 100 or 120V country.

Good luck.

Comment Re: Emergency Brake? (Score 1) 564

Recently towed a loaded, disabled GMC Safari across town and about 15 rural miles with a chain, behind a loaded GMC S15.

Part way through the trip, the brake master cylinder on the Safari turned into a leaky mess and failed to be effective.

For the remainder of the trip, I was stopping both the Safari and the S15 using only the Safari's mechanical parking brake.

Drama: Zero. Smoking brake linings: Zero. Locked wheels: Zero.

I'm sure you're about to patiently explain to me that this is, was, and will always be impossible to accomplish. I'll wait.

Comment Re: Emergency Brake? (Score 1) 564

1. Yep, no lever or pedal. Just a switch on a console, with an orange LED and a soft click somewhere in the guts of the vehicle to indicate that I'd done something. I didn't try to activate it in motion, despite it being a rental car.

2. Never use a parking/e-brake brake like that; in an emergency, FFS, never do anything as hard as you can. But yeah, you can GENTLY slow and stop with one if you're not a dolt with it.

3. The hydraulic brakes felt fine. I'm sure it was split into at a front/rear system, just as cars have been for eons. I didn't detect anything strange about them, or the electrically-assisted power steering (which, contrary to popular belief, works just like traditional power-steering, just with a electric motor-driven pump instead of a belt-driven pump).

Comment Re: Emergency Brake? (Score 1, Insightful) 564


Rented a Chrysler 200S recently. The gear selector was a purely electronic rotary plastic knob with almost zero resistance or mechanical feedback, the parking brake was an electronic button beside it, there was no emergency brake to speak of, and there was no ignition key or mechanical switch, but just a button.

All the R'ing the FM in the world can't fix a stupid design.

Comment Re:You're doing it wrong... (Score 1) 137


1. How do you know it was a surge that killed your PSU?

2. What else was your laptop plugged into when it got roached?

Surges from line-to-neutral are usually taken up by the PSU's own internal MOVs, spark gaps, and other things designed for the purpose (and far better than an average power strip of reasonable expense) of protecting the device. (Or at least this is the case with proper PSUs. No-name Ebay cruft without a UL/CSA/whatever registration is anyone's guess.)

Contrastingly, common-mode surges cannot be dealt with in this way....but they also can't affect anything unless that potential has someplace to go (ie, a complete circuit).

Which, of course, makes perfect sense: Stick one side or the other of a 9V battery against your tongue and nothing happens, but when you stick both sides to your tongue...ow.

So if your laptop was connected to two things (the wall *and* the hotel TV, or the wall *and* the Ethernet jack/phone line, or...), your failure makes more sense.

(and its mA when discussing current flow.)

Comment Re:Easiest things to do. (Score 1) 1838

My two cents:

1. Unicode. Everyone tells me this is an ongoing concern, and so it must be. I for one am perfectly OK with Unicode penis birds with my hot grits.

2. Scores. Yep, that's one of Slashdot's main benefits, and I see no reason to change it. Reddit has free-form scoring; it doesn't need duplicated here.

3. I like the idea of direct messaging. Sure, my email is unobfuscated (and always has been), and I've only been contacted twice -- ever -- in email from another /. user....but maybe people would communicate more freely if their conversations were both private and pseudo-anonymous.

3.5. Journals should be promoted more. There are some interesting people here still, and I wouldn't mind knowing when they rant about something interesting to them.

4. I have wonderful karma, thank you. But the time-between-comments problem has bitten me more times than I care to remember, and more than once I've just said "fuck it" and not posted something that I had already finished writing instead of patiently waiting for a timer of unknown and arbitrary value to expire, clicking "submit" periodically. The delay should be shortened. (In fact, I think it should be eliminated for UIDs less than 21055.)

5/6/7/8. Yep.

9. This is an appropriately elegant solution that also eliminates any concept of revisionist history, which is a good thing.

10. Sigs used to be much, much longer. I used to be able to put a line from a song and a link to the rest of the lyrics into a sig, and now....meh. 200 characters (including any HTML markup!) seems reasonable, and if folks don't like it they can always turn them off.

11. When our fearless leader was still around, before the first buyout (selloff?), it felt much more like a community here. When /. was down, Malda would write about why it was down and how it was fixed -- same with upgrades. When a new editor showed up, there was generally a few words about them. This level of transparency was perfect for a technical audience, but has been dwindling for...fuck, almost 17 years.

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