electronic throttle
in [Technical]
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From: News on 8 Mar 2010 20:34 clare(a)snyder.on.ca wrote: > On Sun, 07 Mar 2010 23:58:57 -0500, News <News(a)Groups.Name> wrote: > >> clare(a)snyder.on.ca wrote: >>> On Sun, 07 Mar 2010 18:05:07 -0500, News <News(a)Groups.Name> wrote: >>> >>>> clare(a)snyder.on.ca wrote: >>>>> On Sun, 7 Mar 2010 11:10:20 -0800, "theref" <theref(a)seanet.com> wrote: >>>>> >>>>>> "Grumpy AuContraire" <GrumpyOne(a)GrumpyvilleNOT.com> wrote in message >>>>>> news:99adnZJAetdSdQ7WnZ2dnUVZ_qidnZ2d(a)giganews.com... >>>>>>> bjn wrote: >>>>>>>> On Sat, 06 Mar 2010 10:38:19 -0500, Bill Putney <bptn(a)kinez.net> wrote: >>>>>>>> >>>>>>>>> jim beam wrote: >>>>>>>>>> if you buy all this fear-mongering idiocy that electronic throttle is a >>>>>>>>>> problem, and that brakes, transmissions and ignition kill switches can >>>>>>>>>> all simultaneously fail causing a driver to lose control, it might be >>>>>>>>>> worth auto manufacturers of all stripes to adopt a slightly different >>>>>>>>>> implementation of electronic throttle [e.t.] - if not for mechanical >>>>>>>>>> reasons, but to shut the idiots up... >>>>>>>>> The lawyers, politicians, and news media can convince the public of the >>>>>>>>> impossible (failure even a totally fail safe system) any time they >>>>>>>>> decide to do it depending on political or monetary motivation. IOW - >>>>>>>>> the people and companies who do a good job of designing are going to get >>>>>>>>> punished anyway (unless they know how to play the game in a corrupt >>>>>>>>> system). There are people in our society whose life goal is to make >>>>>>>>> sure that that happens. >>>>>>>> The problem is that now lawyers, politicians and news media are driving >>>>>>>> (no >>>>>>>> pun intended) solution. The way I see them talking, cars will wind up >>>>>>>> with >>>>>>>> a fail-safe throttle that is more fail-safe than the controls of a jumbo >>>>>>>> passenger jet. >>>>>>>> >>>>>>> I'm not sure about this but for sure... The causes you cite certainly >>>>>>> contributed in getting to where we're at! >>>>>>> >>>>>>> Oh, don't forget that little incident when a B-777's engines went to idle >>>>>>> about a minute before touch down at Heathrow about a year ago. Aircraft >>>>>>> was totaled but there were no major injuries. >>>>>>> >>>>>>> Cause has been assessed to software/computer glitch. >>>>>>> >>>>>>> JT >>>>>> I believe that was traced to icing in the fuel system. SOP now is to cycle >>>>>> fuel after prolonged low temp at altitude. >>>>> Icing on a JET????????? >>>>> Don't think so. >>>> Absolutely. Determined to be cause of BA 777 landing short at Heathrow. >>> >>> OK - I looked it up. Technically this was fuel jelling - common with >>> diesel fuel in arctic conditions. In the case of the Rolls turbines, >>> it was a design fault in the fuel pre-heater unit which resulted in a >>> mandatory replacement with a redesigned heat exchanger. >>> >>> Different than the carb icing on a prop plane. >> It was ice in the fuel blocking the pre-heater, not fuel jelling. Get >> it straight. > So there was water in the fuel? There was an AD put out on those > engines requireing the replacement of the fuel pre-heater heat > exchanger is all I know "for sure". > I also know diesel and Jet A can gel in the cold, which is why > fuel-heaters are used on diesels, and I assume why they are used on > jets. There is ALWAYS water in fuel.
From: News on 8 Mar 2010 20:34 clare(a)snyder.on.ca wrote: > On Mon, 08 Mar 2010 17:07:16 -0500, News <News(a)Group.Name> wrote: > >> Grumpy AuContraire wrote: >>> clare(a)snyder.on.ca wrote: >>>> On Sun, 07 Mar 2010 18:05:07 -0500, News <News(a)Groups.Name> wrote: >>>> >>>>> clare(a)snyder.on.ca wrote: >>>>>> On Sun, 7 Mar 2010 11:10:20 -0800, "theref" <theref(a)seanet.com> wrote: >>>>>> >>>>>>> "Grumpy AuContraire" <GrumpyOne(a)GrumpyvilleNOT.com> wrote in >>>>>>> message news:99adnZJAetdSdQ7WnZ2dnUVZ_qidnZ2d(a)giganews.com... >>>>>>>> bjn wrote: >>>>>>>>> On Sat, 06 Mar 2010 10:38:19 -0500, Bill Putney <bptn(a)kinez.net> >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> jim beam wrote: >>>>>>>>>>> if you buy all this fear-mongering idiocy that electronic >>>>>>>>>>> throttle is a problem, and that brakes, transmissions and >>>>>>>>>>> ignition kill switches can all simultaneously fail causing a >>>>>>>>>>> driver to lose control, it might be worth auto manufacturers of >>>>>>>>>>> all stripes to adopt a slightly different implementation of >>>>>>>>>>> electronic throttle [e.t.] - if not for mechanical reasons, but >>>>>>>>>>> to shut the idiots up... >>>>>>>>>> The lawyers, politicians, and news media can convince the public >>>>>>>>>> of the impossible (failure even a totally fail safe system) any >>>>>>>>>> time they decide to do it depending on political or monetary >>>>>>>>>> motivation. IOW - the people and companies who do a good job of >>>>>>>>>> designing are going to get punished anyway (unless they know how >>>>>>>>>> to play the game in a corrupt system). There are people in our >>>>>>>>>> society whose life goal is to make sure that that happens. >>>>>>>>> The problem is that now lawyers, politicians and news media are >>>>>>>>> driving (no >>>>>>>>> pun intended) solution. The way I see them talking, cars will >>>>>>>>> wind up with >>>>>>>>> a fail-safe throttle that is more fail-safe than the controls of >>>>>>>>> a jumbo >>>>>>>>> passenger jet. >>>>>>>>> >>>>>>>> I'm not sure about this but for sure... The causes you cite >>>>>>>> certainly contributed in getting to where we're at! >>>>>>>> >>>>>>>> Oh, don't forget that little incident when a B-777's engines went >>>>>>>> to idle about a minute before touch down at Heathrow about a year >>>>>>>> ago. Aircraft was totaled but there were no major injuries. >>>>>>>> >>>>>>>> Cause has been assessed to software/computer glitch. >>>>>>>> >>>>>>>> JT >>>>>>> I believe that was traced to icing in the fuel system. SOP now is >>>>>>> to cycle fuel after prolonged low temp at altitude. >>>>>> Icing on a JET????????? >>>>>> Don't think so. >>>>> Absolutely. Determined to be cause of BA 777 landing short at Heathrow. >>>> >>>> OK - I looked it up. Technically this was fuel jelling - common with >>>> diesel fuel in arctic conditions. In the case of the Rolls turbines, >>>> it was a design fault in the fuel pre-heater unit which resulted in a >>>> mandatory replacement with a redesigned heat exchanger. >>>> >>>> Different than the carb icing on a prop plane. >>> >>> Good point. >>> >>> I like to read the whole technical report as opposed to what was >>> published in a paper. >> >> Have at it: >> >> http://www.aaib.gov.uk/publications/formal_reports/1_2010_g_ymmm.cfm >> >> Advise when able. > > > Looks like they suspect water in the fuel, but it does not fully rule > out Gelling (the fuel WAS at -10C) because they only identified > "probable" causual factors. Good luck with your accident investigation career.
From: Bill Putney on 8 Mar 2010 20:59 clare(a)snyder.on.ca wrote: > On Mon, 08 Mar 2010 06:14:04 -0500, Bill Putney <bptn(a)kinez.net> > wrote: > >> clare(a)snyder.on.ca wrote: >>> On Sun, 07 Mar 2010 18:29:44 -0500, Bill Putney <bptn(a)kinez.net> >>>> Actually, after some thought, I can see how it might be done with a >>>> single pot: Pot wiper gets tied to ground, and you run constant current >>>> into each end terminal. The voltages read at the two end terminals will >>>> be inverse of each other (as wiper is moved in one direction, voltage of >>>> one end terminal goes from 0 to R x I, voltage of the other end goes in >>>> the opposite direction). >>>> >>>> Not saying that the designers would have realized that it could be done >>>> like that, but that's the only way I could think of using a single pot. >>> That works too. >> But my way violates the unacceptable ground on an analog input that you >> pointed out. Your method is better. >> >> BUT - you wouldn't even have to raise the ref and its ground. Kind of >> combine our two methods: Tie the wiper to the ref. voltage (gets rid of >> the ground issue), and put a constant current source (sinking) on both >> ends. Scale your constant current and size your pot. such that when the >> wiper is pegged to one end (and reading 5 volts), the voltage on the >> other end is, say, 1 volt. That could be done with a nominal 8 mA >> current source and 500 ohm pot, as an example. The two ends would range >> between 1 and 5 volts (nominal), and be inverse of each other. One >> check the ECM could do is verify that the two voltages at any moment in >> time add up to 6 volts. > > > Quite pssibly how they do it - I was just showing a "simple" example. Oh - no problem. I was just having fun thinking it thru with you. I have no idea how *they* do it. But that's how I would do it. -- Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')
From: Bill Putney on 8 Mar 2010 21:03 clare(a)snyder.on.ca wrote: > On Mon, 08 Mar 2010 15:12:54 -0600, Grumpy AuContraire > <GrumpyOne(a)GrumpyvilleNOT.com> wrote: >> (Who remembers years ago a VW beetle icing up - A little "dry" gas took >> care of the problem quickly) > I had my 49 beetle vapour lock and ice up on the same one-day trip > with weather in the high 80's F ( and roughly 100% humidity) Different situation, but I had a car overheat in what is called a winter hurricane in CO in sub-freezing whether one time - the snow blew so hard that it clogged the radiator fins, and the engine overheated. Reminded me of "Oh Suzanna" - "The sun so hot I froze to death", except the opposite. -- Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')
From: Bill Putney on 8 Mar 2010 21:08
clare(a)snyder.on.ca wrote: > On Mon, 08 Mar 2010 17:55:13 -0500, Bill Putney <bptn(a)kinez.net> > wrote: > >> David Skelton wrote: >> >>> All three had the "air bypass" valve too. >>> >>> I do not know what you mean with "ISC system". >>> >>> BTW, I have known some discreet electronic components that have failed due >>> to being used too near the maximun demand for too long, would you not >>> consider that to be 'wearing out' ?? >> Hah! Yeah - like LED assembly replacements for incandescents that you >> buy off of ebay that use LED's designed for maximum current of X, and in >> the assembly they each dissipate 1.3X so they can advertise brightness >> and compete on an even footing with their competition that is doing the >> same thing. So what if the LED's fail in 6 months - they have your >> money and you already gave them rave reviews. > You Do know that pulsed LEDs CAN run at significantly over rated > current almost indefinitely, providing much brighter output than > normal, with no visible flicker?? > As long as the LED is not caused or allowed to OVERHEAT, it will last > virtually forever. > > Jim Weir of RST Engineering has demonstrated this and provides some > neat "overdriver" circuits. Yes - you pulse it at higher *instantaneous* current, but you duty cycle it such that the *average* power is within what it can tolerate. BUT - the human eye registers the pulse peaks more than the average, so it is a trick to run it within the rated average power but the eye *perceives* it as more power than it really is. -- Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x') |