EV Digest 5039
Topics covered in this issue include:
1) Re: I want to build a PWM DC motor controller
by Stefan Peters <[EMAIL PROTECTED]>
2) Re: Electron flows and heating
by Doug Weathers <[EMAIL PROTECTED]>
3) Re: Small car, Big heart
by David Dymaxion <[EMAIL PROTECTED]>
4) Re: Electron flows and heating
by Danny Miller <[EMAIL PROTECTED]>
5) AC motor drive demonstrator
by Neon John <[EMAIL PROTECTED]>
6) Re: AC motor drive demonstrator
by Neon John <[EMAIL PROTECTED]>
7) Re: Zombie at DragTimes Web Site
by "Philippe Borges" <[EMAIL PROTECTED]>
8) ion battery
by "torich1" <[EMAIL PROTECTED]>
9) EDTA
by "torich1" <[EMAIL PROTECTED]>
10) IGBT inside view
by Neon John <[EMAIL PROTECTED]>
11) RE: Need to ask a general question about torque converters
by "Dewey, Jody R ATC (CVN75 IM3)" <[EMAIL PROTECTED]>
12) Valence (was: 24ah 240vdc Li Ion pack)
by Osmo Sarin <[EMAIL PROTECTED]>
13) Re: Valence (was: 24ah 240vdc Li Ion pack)
by "Philippe Borges" <[EMAIL PROTECTED]>
14) Re: I want to build a PWM DC motor controller,safety & reliability
by "Mark Hanson" <[EMAIL PROTECTED]>
15) Re: EV acceptance idea
by Fortunat Mueller <[EMAIL PROTECTED]>
16) RE: Hybrid motor mounting, poof goes the car
by Electro Automotive <[EMAIL PROTECTED]>
17) Re: Zombie at DragTimes Web Site
by "Roderick Wilde" <[EMAIL PROTECTED]>
18) Re: Zombie at DragTimes Web Site, Correction
by "Roderick Wilde" <[EMAIL PROTECTED]>
19) Re: Are these chargers any different?
by Eric Poulsen <[EMAIL PROTECTED]>
20) "White Zombie" now in the top 100 cars
by "Roderick Wilde" <[EMAIL PROTECTED]>
21) Re: AC motor drive demonstrator
by Doug Weathers <[EMAIL PROTECTED]>
22) Re: Zombie at DragTimes Web Site
by "Dave Davidson" <[EMAIL PROTECTED]>
23) 2006 Elections
by Doc Kennedy <[EMAIL PROTECTED]>
24) charger mounting
by brian baumel <[EMAIL PROTECTED]>
25) Re: charger mounting
by Doug Weathers <[EMAIL PROTECTED]>
26) Re: Need to ask a general question about torque converters
by Ryan Stotts <[EMAIL PROTECTED]>
27) Re: Zombie at DragTimes Web Site
by "Roderick Wilde" <[EMAIL PROTECTED]>
28) Re: 2006 Elections
by Rush <[EMAIL PROTECTED]>
29) Re: Madman is NOT Happy!
by Electro Automotive <[EMAIL PROTECTED]>
--- Begin Message ---
Lee Hart wrote:
Stefan T. Peters wrote:
Anyone know of a optoisolator suitable for this: [snip...]
This is for ground loop isolation for the gate of an International
Rectifier ISP0551T MOSFET switch.
You didn't provide enough details to allow finding a "perfect" fit. But
judging from the MOSFET part# you provided, what you need is a logic
optocoupler that has an internal IC that provides a TTL-compatible
output for the gate driver inside the ISP0551T. When I did something
similar to this, I used an Agilent HCPL-2211.
You got it dead on. Thanks a bunch!
--- End Message ---
--- Begin Message ---
On Dec 29, 2005, at 8:01 AM, Lee Hart wrote:
...positive brushes get hotter than the negative brushes (due to the
electron flow)... welder electrodes... battery terminals...
There are lots of things going on at once here.
<snip an excellent and clear tutorial>
My view (and apparently Victor's) was only of electrons circling in a
conductor, with electrons moving one direction and "holes" moving in
the other. Clearly everything is symmetrical and there shouldn't be an
asymmetrical increase of heat anywhere. I didn't see how relativity
and parity could be so obviously violated in motors and batteries
without being noticed by a physicist, hence my curiosity.
If I'm understanding aright, my question is answered: there are two
separate phenomena here. One is the heating effect that occurs when an
electron enters a conductor (and the corresponding cooling effect when
it leaves one), which explains the hotter positive brush and arc
welding electrode. The other phenomenon is something electrochemical
happening in the battery, which Lee didn't fully explain but which I'm
perfectly willing to believe in, given the evidence and Lee's
experience in battery chemistry. The cooling effect of evaporating
electrode material probably won't have much impact on DC brushes since
we know that they last much, much longer than a welding rod and
therefore can't be losing very much material.
James Massey and Andre' Blanchard also explained parts of the puzzle
but it was Lee's explanation that penetrated my skull. Thanks, all.
A most delightful digression, thanks everyone for your patience. I now
return you to your irregularly scheduled list traffic :)
--
Lee A. Hart 814 8th Ave N Sartell MN 56377
leeahart_at_earthlink.net
--
Doug Weathers
Bend, OR, USA
http://learn-something.blogsite.org
--- End Message ---
--- Begin Message ---
I like how you are thinking!
I'd add a Mini Cooper to your list for consideration. I've read you
can remove 140 lbs just by switching wheels and tires. Hondas seem to
be popular race cars, so they'd be another good choice for
aftermarket parts.
You might also consider a lighter Hawker AGM for such a car (like 25
lbs each) instead of a heavier 41 lb Orbital.
The transmissions in those little cars are not up to the full torque
you could make. You'll have to limit power a bit, or run with
slippery street tires.
--- Chris Buresh <[EMAIL PROTECTED]> wrote:
> I've been trying to assess different vehicles to convert into a fun
> car with surprising performance. Recently, the idea of a Metro,
> Festiva, Aspire, etc. type vehicle loaded with excessive power has
> caught my fancy. Range is not too big of a concern - 25 miles
> without having to baby it would be fine. I could see upto 300V of
> AGMs using a Z1k and Warp 9. Obviously, this setup may be
> overkill. I would tame it down (but not much) to fit the
> application into the small donor. Loads of aftermarket detailling
> and mods are options to get one of these ordinary rollerskates
> turning heads.
>
> My question to the list:
>
> Which car would be a good platform for this outcome? I know
> nothing about the frame or suspension of these vehicles. Would I
> need to beef them up to hold the battery weight and handle the
> power?
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
I've got no clear explanation either but electrons do not "evaporate"
like atoms do, nor can they really be said to have a "temperature" or
the ability to carry heat the way a solid material does. In some ways
you could try to fit the known physics effects into these concepts but
it's not an effective methaphor for explaining it.
One explanation would come down to the junction between two dissimilar
materials can present a different impedance depending on the current
direction. In one brush, the current flows from carbon to copper and in
the other, copper to carbon. For example, a zener diode will drop 0.7v
if the current is flowing one direction but drops 5v if the current is
flowing the other direction. When the current is identical in both
directions (as it is here), the heat generated is directly proportional
to the voltage drop. The effect need not be very strong to produce
noticible temp differences under high currents.
But the thermoelectric rules- Peltier/Seebeck effect and the Thompson
Effect- are also candidates. Thompson Effect could be a plausible cause:
"In metals such as zinc <http://en.wikipedia.org/wiki/Zinc> and copper
<http://en.wikipedia.org/wiki/Copper>, which have a hotter end at a
higher potential and a cooler end at a lower potential, when current
moves from the hotter end to the colder end, it is moving from a high to
a low potential, so there is an evolution of energy. When it moves from
the colder to the hotter end, there is an energy absorption. This is
called the positive Thomson effect.
In metals such as cobalt <http://en.wikipedia.org/wiki/Cobalt>, nickel
<http://en.wikipedia.org/wiki/Nickel>, and iron
<http://en.wikipedia.org/wiki/Iron>, which have a cooler end at a higher
potential and a hotter end at a lower potential, when current moves from
the hotter end to the colder end, it is moving from a low to a high
potential, there is an absorption of energy. When it moves from the
colder to the hotter end, there is an energy evolution. This is called
the negative Thomson effect."
http://en.wikipedia.org/wiki/Peltier_effect
Carbon has a Seebeck coefficient of 3.0, copper 6.5... not a significant
difference so it's unlikely a thermoelectric Peltier effect is pumping
heat across the junction.
Danny
--- End Message ---
--- Begin Message ---
International Rectifier made an evaluation board that let one connect
up to a 1/2 hp, 3 phase motor to the board and then learn about how 3
phase AC drives work. The board demonstrated their IRAMS10UP60A chip,
an all-in-one AC driver capable of driving up to 1/2 horse motors.
The datasheet is here:
http://www.irf.com/technical-info/refdesigns/iradk10.pdf
The chip datasheet is here:
http://www.irf.com/product-info/datasheets/data/irams10up60a.pdf
IR's page on the device is here:
http://ec.irf.com/v6/en/US/adirect/ir?cmd=catSearchFrame&domSendTo=byID&domProductQueryName=iradk10
The board is listed as OBSOLETE but Allied lists at least one in
stock.
This looks to be a great learning tool. After learning, you can make
your drill press variable speed :-)
John
---
John De Armond
See my website for my current email address
http://www.johngsbbq.com
Cleveland, Occupied TN
A foolish consistency is the hobgoblin of little minds.-Ralph Waldo Emerson
--- End Message ---
--- Begin Message ---
Following up myself, here's an even better one, as the chip uses
external power devices and is current production:
http://ec.irf.com/v6/en/US/adirect/ir?cmd=catSearchFrame&domSendTo=byID&domProductQueryName=irmcs2031
On Fri, 30 Dec 2005 04:00:32 -0500, Neon John <[EMAIL PROTECTED]>
wrote:
>International Rectifier made an evaluation board that let one connect
>up to a 1/2 hp, 3 phase motor to the board and then learn about how 3
>phase AC drives work. The board demonstrated their IRAMS10UP60A chip,
>an all-in-one AC driver capable of driving up to 1/2 horse motors.
>
>The datasheet is here:
>
>http://www.irf.com/technical-info/refdesigns/iradk10.pdf
>
>The chip datasheet is here:
>
>http://www.irf.com/product-info/datasheets/data/irams10up60a.pdf
>
>IR's page on the device is here:
>
>http://ec.irf.com/v6/en/US/adirect/ir?cmd=catSearchFrame&domSendTo=byID&domProductQueryName=iradk10
>
>The board is listed as OBSOLETE but Allied lists at least one in
>stock.
>
>This looks to be a great learning tool. After learning, you can make
>your drill press variable speed :-)
>
>John
>---
>John De Armond
>See my website for my current email address
>http://www.johngsbbq.com
>Cleveland, Occupied TN
>A foolish consistency is the hobgoblin of little minds.-Ralph Waldo Emerson
>
---
John De Armond
See my website for my current email address
http://www.johngsbbq.com
Cleveland, Occupied TN
A foolish consistency is the hobgoblin of little minds.-Ralph Waldo Emerson
--- End Message ---
--- Begin Message ---
This is my favorite, with such picture no need to describe the car, all is
said !
cordialement,
Philippe
waiting for white zombie in the 11,xx :^)
Et si le pot d'échappement sortait au centre du volant ?
quel carburant choisiriez-vous ?
http://vehiculeselectriques.free.fr
Forum de discussion sur les véhicules électriques
http://vehiculeselectriques.free.fr/Forum/index.php
----- Original Message -----
From: "John Wayland" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, December 30, 2005 12:44 AM
Subject: Re: Zombie at DragTimes Web Site
> Hello to All,
>
> Ryan Stotts wrote:
>
> >How big does the pic need to be?
> >
> >http://img506.imageshack.us/img506/3654/zw8ow.jpg
> >
> >Load up one of your movies and pause it and press the print screen key
> >on your keyboard then load up one of your image programs and select
> >edit, then paste. Then cut the pic you want away from the rest of the
> >image.
> >
> >
> >
> That's an image from video Marko Mongillo took using my
> less-than-state-of-the-art, standard Hi 8 video cam, that I clipped away
> and made a still of. I was hoping to have better quality than this, but
> it 'is' a fun shot!
>
> Maybe I should quit being so picky and send this picture in....
>
> See Ya.....John Wayland
>
--- End Message ---
--- Begin Message ---
http://www.theautochannel.com/news/2005/12/18/182241.html
--- End Message ---
--- Begin Message ---
http://www.electricdrive.org/
--- End Message ---
--- Begin Message ---
Views of the internals of a 1200 volt, 400 amp IGBT that leaked its
blue smoke:
http://forum.4hv.org/index.php?board=4;action=display;threadid=1181
---
John De Armond
See my website for my current email address
http://www.johngsbbq.com
Cleveland, Occupied TN
A foolish consistency is the hobgoblin of little minds.-Ralph Waldo Emerson
--- End Message ---
--- Begin Message ---
You would waste A LOT of energy by using a torque converter. You don't need
torque multiplication - DC motors have plenty of starting torque. Just use
a regular stick shift transmission and couple it directly to the motor or
use a clutch. Either way it will work fine.
-----Original Message-----
From: Jeff Shanab [mailto:[EMAIL PROTECTED]
Sent: Thursday, December 29, 2005 9:37 PM
To: Electric Vehicle Discussion List
Subject: Need to ask a general question about torque converters
If I was to place a torque converter in place of the clutch and use a
standard transmission, how would that work/notwork?
Could I set the controller for an idle rpm to run accessories and then
just step on gas to accelerate from a stop. In this way leaveing it in
say 3rd gear since the torque converter would give me some
multiplication off line and then perhaps lock in the TCC if above x mph
and < y throttle?
Could I shift or would I get a bad whirrrr-bang?
--- End Message ---
--- Begin Message ---
4) Valence batteries are half the energy density and approx 30% more
in cost
than Kokam batteries. Their literature suggests 2000 lifecycles, but
no
hard data has been found for EVs - more investigation is required.
Here is a little piece of information about Valence I got from a
canadian company called Les Industries Alternativ Inc. I´m sure they
don´t mind sharing it.
Osmo Sarin
-----
"We are using Valence li-ion batteries since july 2004. We
do think those are the safest on the market and the least injurious for
the environment.
We also did our own tests in the safety department : we had a car crash
in march with one of our converted vehicle. We hit a loader in a snow
storm and the result was great. The car was heavily damaged but the
batteries did great. A few cells were damaged but there was no leak,
fire, smoke or anything else. We just had to replace the damaged cells
to make them work like before our little incident...and find a new
vehicle to transfer the batteries in !!!!! The batteries reacted exactly
like Valence expectations.
About the price issue, Valence batteries are expensive but we are truly
satisfied with the product we have in hands. Their properties make them
worth the extra money.
...the batteries we are using are guaranteed for 2000 cycles
and yes they seems to be really realistic till now."
28.12.2005 kello 23:55, Don Cameron kirjoitti:
Yes there are "bad" manufacturers of cheap Li-Ion cells. There are
some
"good" ones too. I suggest that before implying that all LiIon
batteries
are unsafe, shop around and investigate. Get to know the safety
standards
and their limitations.
A few points to make:
1) Kokam batteries are lithium polymer.
2) Kokam batteries have passed six standardized tests for fire and
explosion
under the standards SBA G1101 and UL1642. This includes overcharge,
heating,
crush, impact, forced discharge.
3) Cliff at proev.com is currently evaluating Kokam batteries in
autocross
racing applications. Although his information will largely be
anecdotal, it
will be useful to see the battery lifetime under these conditions.
3) You may be referring to Valance U-Charge using their "Saphion"
technology. These batteries, as well, passed the UL1642 tests.
4) Valence batteries are half the energy density and approx 30% more
in cost
than Kokam batteries. Their literature suggests 2000 lifecycles, but
no
hard data has been found for EVs - more investigation is required.
5) Valance states that UL1642 is a poor standard as small, liquid
lithium
batteries can pass the test. Others suggest that this is a difficult
test
for large cells to pass. Not sure if this is FUD from Valence or
factual
information - more investigation is required.
You may want to investigate the archives. There was a great thread
between
Jukka and David Lalonde about testing of Thundersky batteries and these
standards.
YMMV - investigate before committing.
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Danny Miller
Sent: December 28, 2005 11:14 AM
To: [email protected]
Subject: Re: 24ah 240vdc Li Ion pack.
Now keep in mind there's another issue than cost that keeps Li-Ion
down as a
high capacity storage system.
Li-Ion is extremely flammable. That can occur through improper or just
nonideal charging procedures, mechanical damage (collision/vibration),
or
mfg defects in cheapo cells. The problem gets more severe as the
battery
size is scaled up. I don't think many smaller cells are better
either, the
failure potential of any one cell is of course multiplied by the
number of
cells. Not that this necessarily means all the cells are on fire at
that
point but there is a cell on fire in the middle of the pack. The bad
part
here is that there's no good way to properly charge this many cells
and a
hokey charge procedure is almost doomed to failure.
There have been incidents of cell phone batteries bursting into flames
in
normal duty, often for no apparent reason. The mfgs like to say it's
all
due to cheaper aftermarket battery replacements.
Of course there are big cells designed for EVs. There's that one mfg
mentioned here several months ago that modified the technology to be
nonflammable. That would make sense. Of course the problems of cost
or
even availability are pretty bad.
Danny
Don Cameron wrote:
Lawrence, you had me going a bit crazy. The subject of the email said
"240V" $4600 for 24Ah 240V would change the face of EVs overnight!
Don
--- End Message ---
--- Begin Message ---
Valence clip is a good commercial idea as they choose to make a video using
Li-ion cobalt electrode which give most powerful AND most unstable 18650
type li-ion cells.
These are not in use for public application since...many many years, every
company selling li-ion 18650 to public market switched to manganese
electrode for safety reason.
Better having 160Wh/kg stable than 190wh/kg "uncontrolable"
I have new version 18650 type manganese based 2,2Ah for a pack design
project i have so will make my own torture test video this week and see...
This said, i think Valence battery type are the right way to go (maximum
safety target) and wish them great success.
cordialement,
Philippe
Et si le pot d'échappement sortait au centre du volant ?
quel carburant choisiriez-vous ?
http://vehiculeselectriques.free.fr
Forum de discussion sur les véhicules électriques
http://vehiculeselectriques.free.fr/Forum/index.php
----- Original Message -----
From: "Osmo Sarin" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, December 30, 2005 12:06 PM
Subject: Valence (was: 24ah 240vdc Li Ion pack)
> > 4) Valence batteries are half the energy density and approx 30% more
> > in cost
> > than Kokam batteries. Their literature suggests 2000 lifecycles, but
> > no
> > hard data has been found for EVs - more investigation is required.
>
> Here is a little piece of information about Valence I got from a
> canadian company called Les Industries Alternativ Inc. I´m sure they
> don´t mind sharing it.
>
> Osmo Sarin
>
> -----
> "We are using Valence li-ion batteries since july 2004. We
> do think those are the safest on the market and the least injurious for
> the environment.
>
> We also did our own tests in the safety department : we had a car crash
> in march with one of our converted vehicle. We hit a loader in a snow
> storm and the result was great. The car was heavily damaged but the
> batteries did great. A few cells were damaged but there was no leak,
> fire, smoke or anything else. We just had to replace the damaged cells
> to make them work like before our little incident...and find a new
> vehicle to transfer the batteries in !!!!! The batteries reacted exactly
> like Valence expectations.
>
> About the price issue, Valence batteries are expensive but we are truly
> satisfied with the product we have in hands. Their properties make them
> worth the extra money.
>
> ...the batteries we are using are guaranteed for 2000 cycles
> and yes they seems to be really realistic till now."
>
>
>
>
>
> 28.12.2005 kello 23:55, Don Cameron kirjoitti:
>
> Yes there are "bad" manufacturers of cheap Li-Ion cells. There are
> some
> > "good" ones too. I suggest that before implying that all LiIon
> > batteries
> > are unsafe, shop around and investigate. Get to know the safety
> > standards
> > and their limitations.
> >
> >
> > A few points to make:
> >
> > 1) Kokam batteries are lithium polymer.
> >
> > 2) Kokam batteries have passed six standardized tests for fire and
> > explosion
> > under the standards SBA G1101 and UL1642. This includes overcharge,
> > heating,
> > crush, impact, forced discharge.
> >
> > 3) Cliff at proev.com is currently evaluating Kokam batteries in
> > autocross
> > racing applications. Although his information will largely be
> > anecdotal, it
> > will be useful to see the battery lifetime under these conditions.
> >
> > 3) You may be referring to Valance U-Charge using their "Saphion"
> > technology. These batteries, as well, passed the UL1642 tests.
> >
> > 4) Valence batteries are half the energy density and approx 30% more
> > in cost
> > than Kokam batteries. Their literature suggests 2000 lifecycles, but
> > no
> > hard data has been found for EVs - more investigation is required.
> >
> > 5) Valance states that UL1642 is a poor standard as small, liquid
> > lithium
> > batteries can pass the test. Others suggest that this is a difficult
> > test
> > for large cells to pass. Not sure if this is FUD from Valence or
> > factual
> > information - more investigation is required.
> >
> > You may want to investigate the archives. There was a great thread
> > between
> > Jukka and David Lalonde about testing of Thundersky batteries and these
> > standards.
> >
> >
> > YMMV - investigate before committing.
> >
> >
> >
> >
> > Victoria, BC, Canada
> >
> > See the New Beetle EV Conversion Web Site at
> > www.cameronsoftware.com/ev/
> >
> > -----Original Message-----
> > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
> > Behalf Of Danny Miller
> > Sent: December 28, 2005 11:14 AM
> > To: [email protected]
> > Subject: Re: 24ah 240vdc Li Ion pack.
> >
> > Now keep in mind there's another issue than cost that keeps Li-Ion
> > down as a
> > high capacity storage system.
> > Li-Ion is extremely flammable. That can occur through improper or just
> > nonideal charging procedures, mechanical damage (collision/vibration),
> > or
> > mfg defects in cheapo cells. The problem gets more severe as the
> > battery
> > size is scaled up. I don't think many smaller cells are better
> > either, the
> > failure potential of any one cell is of course multiplied by the
> > number of
> > cells. Not that this necessarily means all the cells are on fire at
> > that
> > point but there is a cell on fire in the middle of the pack. The bad
> > part
> > here is that there's no good way to properly charge this many cells
> > and a
> > hokey charge procedure is almost doomed to failure.
> >
> > There have been incidents of cell phone batteries bursting into flames
> > in
> > normal duty, often for no apparent reason. The mfgs like to say it's
> > all
> > due to cheaper aftermarket battery replacements.
> >
> > Of course there are big cells designed for EVs. There's that one mfg
> > mentioned here several months ago that modified the technology to be
> > nonflammable. That would make sense. Of course the problems of cost
> > or
> > even availability are pretty bad.
> >
> > Danny
> >
> > Don Cameron wrote:
> >
> >> Lawrence, you had me going a bit crazy. The subject of the email said
> >> "240V" $4600 for 24Ah 240V would change the face of EVs overnight!
> >>
> >> Don
> >>
> >>
> >>
> >
>
--- End Message ---
--- Begin Message ---
Hi,
That's why it's good to have a manual over-ride for anything critical that
might fail that's controlled by a uP (or just have the uP do monitoring,
something that it's more cost effective at doing). I have an engage
contactor on my uP controlled speed control (and one's designed at GE-EV)
that opens everytime you release the accelerator peddle that's connected to
the peddle microswitch (independent of uP control). I also use a bypass
contactor across the controller tied to a full on microswitch. So if the
controller shorts or the uP goes bonkers, the natural reaction is to release
the accelerator peddle and the controller shuts off. Also if a Mack truck
is following you on the freeway and the controller opens, you can mash the
peddle down and get to the next exit.
Mark
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, December 30, 2005 3:52 AM
Subject: Re: I want to build a PWM DC motor controller
> Danny Miller wrote:
> > I'm not sure where you're getting your information, but much of this
> > is inaccurate at least for modern parts... have you actually used a
> > microcontroller itself?
>
> Oh, but I have; this list *is* relevant for the micros being used right
> now! If you have a Honeywell or Robertshaw electronic control in your
> home furnace, built in the 1980s or 90s, the odds are good that I did
> design work on it. About half of these controls use discrete logic; the
> other half are micro-based. I have considerable experience in both
> camps.
>
> Your responses suggest an overconfidence that comes from a lack of
> experience ("duh, so don't set it up this way"... "duh, this would be
> foolish coding practice"... "wow, we're just grasping at straws"...
>
> Every single one of the watchdog failures I described *has* happened to
> real products, designed by people who thought they knew what they were
> doing. They thought something couldn't happen, so they didn't design for
> it, or test for it. The consequences included fires, explosions,
> injuries, and even deaths! Ignorance and hubris.
>
> Fail-safe design is a hugely complex topic; far larger than can be
> covered in a few emails. Whole books can be written on this topic. My
> little list was just a tiny fragment of the things that can go wrong,
> and only related to the mistakes one could make in just the watchdog
> circuit of a microcontroller. There are many, many more possible errors!
>
> The heart of a fail-safe design is to do a FMEA (Failure Mode Effect
> Analysis). This is a systematic way to explore what might go wrong, what
> will happen if it does, and what you can do to prevent bad outcomes.
>
> 1. List every single part in your circuit.
> (R1, C1, PCB, etc.)
>
> 2. List all the possible failure modes for each part.
> (fails shorted, open, wrong value, etc.)
>
> 3. Simulate one of these failures in the circuit, and see what happens:
> If it makes the product fail safe (for example, it blows a fuse and
> thus safely shuts it off), then mark this as a "safe" failure, and
> continue with the next part/failure mode.
>
> 4. If the failure has no effect (product seems to still work normally);
> then leave it in place and add the next part/failure mode and repeat.
> (For example, shorting temperature sensor TH1 has no effect. So
> leave it shorted and add another failure to see if an undetected
> failure can lead to subsequent failures).
>
> 5. If the results are uncertain (can't predict the consequences based
> on theory); then actually create that failure, and test the circuit.
> Only mark it as a "safe" failure if confirmed by actual testing.
> (For example, theory says that if C1 shorts, it might start a fire;
> but in actual testing, a shorted C1 burns itself open without
> starting a fire or causing other dangerous results.)
>
> 6. If the failure causes a safety-critical result; then redesign to
> eliminate this failure mode (i.e. if R1 shorts, it causes a fire;
> so use a special UL-listed resistor that is guaranteed not to fail
> shorted).
>
> 7. Repeat for every possible failure of every part. If any produce
> unsafe conditions, change the design and retest until
> all such failure modes are eliminated.
>
> FMEA testing often fills thick volumes with data, and can require months
> or years of design and verification. There can be thousands, or even
> millions of possible failure modes to examine!
>
> Micros are difficult to use in safe designs because they introduce
> MILLIONS of possible failure modes, many of which are incredibly
> difficult to test. How do you find out the consequences of transistor
> Q56234 failing in the chip? Especially when the chip's manufacturer
> won't help (trust us...)!
>
> So with micros, you see redundant designs (multiple micros, each
> checking on the others), or partitioned designs (micro not allowed to
> control anything dangerous), or custom chip designs (where dangerous
> failure modes are specifically eliminated).
>
> The alternative of discrete circuitry is often easier. There are fewer
> parts to consider, and fewer failure modes per part for discrete
> resistors, capacitors, diodes, transistors, etc. And, you can get
> special versions of these parts that guarantee that certain failure
> modes won't happen (resistors guaranteed to fail open, transistors that
> can't latch up or be static zapped, etc.).
>
> Finally, there are circuits that can provide fail-safe operation. We can
> (and probably should) discuss some of them; they are useful for anyone
> concerned with safety. They add parts and cost, but also greatly enhance
> safety. A fuse is a very simple example; it blows to shut down a circuit
> *before* anything bad happens.
> --
> Ring the bells that you can ring
> Forget the perfect offering
> There is a crack in everything
> That's how the light gets in
> -- Leonard Cohen
> --
> Lee A. Hart 814 8th Ave N Sartell MN 56377
> [EMAIL PROTECTED]
>
--- End Message ---
--- Begin Message ---
--- Michaela Merz <[EMAIL PROTECTED]> wrote:
> This is why I suggested we define a set of
> 'measurements' and maybe we are
> able to agree on something to define the 'range' as
> something like the
> distance a vehicle is able to travel on a set temp.,
> on a flat hard
> surface with a defined speed until the battery
> reaches a defined DOD
> level.
a good suggestion. What I have missed while planning
my various conversions is a list of power required for
a constant speed (better yet, currrent and voltage).
This would normalize various people's range estimates
for battery type and willingness to drive the car to
the packs edge.
i would love it if people would include in their EV
album entries the following table ;
speed, voltage, current
10 mph
20 mph
30mph
40 mph
50 mph etc
~fortunat
__________________________________
Yahoo! for Good - Make a difference this year.
http://brand.yahoo.com/cybergivingweek2005/
--- End Message ---
--- Begin Message ---
At 06:45 PM 12/29/05 -0700, you wrote:
Mike, how to you make the transition from inside the car to outside the car?
If you have to go through the sheet metal, is there an adapter for the spa
hose?
On the Voltsrabbit, it never goes inside the car. It starts in the engine
compartment, coming up between the steering rack and the body. Under the
car, it follows the path of the exhaust system, mounted with hose clamps
and "L" brackets. In the back, it stops at the end of the frame tunnel,
and just the cables get routed into the hatchback area.
I don't know of any adaptor to run the hose through the sheet metal.
Mike Brown
Electro Automotive POB 1113 Felton CA 95018-1113 Telephone 831-429-1989
http://www.electroauto.com [EMAIL PROTECTED]
Electric Car Conversion Kits * Components * Books * Videos * Since 1979
--- End Message ---
--- Begin Message ---
John's "White Zombie" now has 42 votes. 8 more and he will be listed in the
top 100. Come on folks, even if you don't believe in EV drag racing these
are still electric cars and this does increase the awareness of them. Go
here to vote for John's car
http://www.dragtimes.com/Datsun-1200-Timeslip-7484.html and go here to vote
for Matt's Nissan 240SX http://www.dragtimes.com/Nissan-240SX-Timeslip-7382.
We must have more than 42 EV enthusiasts on this list.
Roderick Wilde
"Suck Amps EV Racing"
www.suckamps.com
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.371 / Virus Database: 267.14.9/216 - Release Date: 12/29/2005
--- End Message ---
--- Begin Message ---
Oops, Matt's correct URL to vote for his car is
http://www.dragtimes.com/Nissan-240SX-Timeslip-7382.html I had mistakenly
left off the html
Roderick Wilde
"Suck Amps EV Racing"
www.suckamps.com
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.371 / Virus Database: 267.14.9/216 - Release Date: 12/29/2005
--- End Message ---
--- Begin Message ---
FWIW, They don't mention if they're isolated or not. Other than that,
looks like they're CC/CV, which is good. Also, doesn't look like they
make a model > 7A.
Ryan Stotts wrote:
Is there anything different about these chargers compared to others?
http://www.ctek.com/us/home.asp
--- End Message ---
--- Begin Message ---
"White Zombie" an electric drag car is now listed in the top 100 cars out of
6,601 cars at www.dragtimes.com Keep them votes comming. We should fill this
site up with as many electrics as possible.
Roderick Wilde
"Suck Amps EV Racing"
www.suckamps.com
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.371 / Virus Database: 267.14.9/216 - Release Date: 12/29/2005
--- End Message ---
--- Begin Message ---
On Dec 30, 2005, at 1:21 AM, Neon John wrote:
Following up myself, here's an even better one, as the chip uses
external power devices and is current production:
http://ec.irf.com/v6/en/US/adirect/ir?
cmd=catSearchFrame&domSendTo=byID&domProductQueryName=irmcs2031
It says it's for Permanent Magnet AC motors. Would that be a problem?
---
John De Armond
See my website for my current email address
http://www.johngsbbq.com
Cleveland, Occupied TN
A foolish consistency is the hobgoblin of little minds.-Ralph Waldo
Emerson
--
Doug Weathers
Bend, OR, USA
http://learn-something.blogsite.org
--- End Message ---
--- Begin Message ---
I voted! I also made a comment/question for the gassers who see John's car
(everyone on this list already knows the answer ;^)
Dave
From: "Roderick Wilde" <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: <[email protected]>
Subject: Re: Zombie at DragTimes Web Site
Date: Fri, 30 Dec 2005 08:29:28 -0800
John's "White Zombie" now has 42 votes. 8 more and he will be listed in the
top 100. Come on folks, even if you don't believe in EV drag racing these
are still electric cars and this does increase the awareness of them. Go
here to vote for John's car
http://www.dragtimes.com/Datsun-1200-Timeslip-7484.html and go here to vote
for Matt's Nissan 240SX
http://www.dragtimes.com/Nissan-240SX-Timeslip-7382. We must have more than
42 EV enthusiasts on this list.
Roderick Wilde
"Suck Amps EV Racing"
www.suckamps.com
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.371 / Virus Database: 267.14.9/216 - Release Date: 12/29/2005
--- End Message ---
--- Begin Message ---
Fellow EAA members,
Am I the only one to get my ballot for the new Board of Directors on Friday
the 30th of Dec.
and have to have it postmarked , not later than Dec.31 a saturday and the
P.O.s in my
county are closed! Gee, wouldn't an earlier mailing or a later deadline
have been more
appropriate?
Sorry for the rant, Doc Kennedy SW Virginia
--- End Message ---
--- Begin Message ---
greetings all,
I just finished mounting my NG3 in my EV and I forgot
to include some rubber for dampening... how durable
are these things? has anyone broke one? will it be
worth the hour of disassembling and re-assembling to
save my $900 charger?
happy holidays and stuff
Brian
__________________________________________
Yahoo! DSL Something to write home about.
Just $16.99/mo. or less.
dsl.yahoo.com
--- End Message ---
--- Begin Message ---
On Dec 30, 2005, at 12:44 PM, brian baumel wrote:
will it be
worth the hour of disassembling and re-assembling to
save my $900 charger?
I'd say that $900/hour is a pretty good rate of pay. I'd take it :)
--
Doug Weathers
Bend, OR, USA
http://learn-something.blogsite.org
--- End Message ---
--- Begin Message ---
Jeff Shanab wrote:
> If I was to place a torque converter in place of the clutch and use a
> standard transmission, how would that work/notwork?
It's basically a fluid coupling. Lots of slip. Even inefficient for
gas powered vehicles. If the motor did not have to idle, I'd bet they
wouldn't even use them.
--- End Message ---
--- Begin Message ---
I also made a comment as a response to a comment from someone else. John
votes have almost doubled since this morning. He is currently at 82 votes.
We still have a way to go to get him on the front page. To vote for John's
car go to http://www.dragtimes.com/Datsun-1200-Timeslip-7484.html, to vote
for Matt's car go to
http://www.dragtimes.com/Nissan-240SX-Timeslip-7382.html
Roderick Wilde
"Suck Amps EV Racing"
www.suckamps.com
----- Original Message -----
From: "Dave Davidson" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, December 30, 2005 12:02 PM
Subject: Re: Zombie at DragTimes Web Site
I voted! I also made a comment/question for the gassers who see John's car
(everyone on this list already knows the answer ;^)
Dave
From: "Roderick Wilde" <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: <[email protected]>
Subject: Re: Zombie at DragTimes Web Site
Date: Fri, 30 Dec 2005 08:29:28 -0800
John's "White Zombie" now has 42 votes. 8 more and he will be listed in
the top 100. Come on folks, even if you don't believe in EV drag racing
these are still electric cars and this does increase the awareness of
them. Go here to vote for John's car
http://www.dragtimes.com/Datsun-1200-Timeslip-7484.html and go here to
vote for Matt's Nissan 240SX
http://www.dragtimes.com/Nissan-240SX-Timeslip-7382. We must have more
than 42 EV enthusiasts on this list.
Roderick Wilde
"Suck Amps EV Racing"
www.suckamps.com
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.371 / Virus Database: 267.14.9/216 - Release Date: 12/29/2005
--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.371 / Virus Database: 267.14.9/216 - Release Date: 12/29/2005
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.371 / Virus Database: 267.14.9/216 - Release Date: 12/29/2005
--- End Message ---
--- Begin Message ---
Hmmm, come to think of it, I never even got one...
Rush
Tucson AZ
www.ironandwood.org
----- Original Message -----
From: "Doc Kennedy" <[EMAIL PROTECTED]>
To: "EV List" <[email protected]>
Sent: Friday, December 30, 2005 1:39 PM
Subject: 2006 Elections
> Fellow EAA members,
>
> Am I the only one to get my ballot for the new Board of Directors on Friday
> the 30th of Dec.
> and have to have it postmarked , not later than Dec.31 a saturday and the
> P.O.s in my
> county are closed! Gee, wouldn't an earlier mailing or a later deadline
> have been more
> appropriate?
>
> Sorry for the rant, Doc Kennedy SW Virginia
>
>
>
--- End Message ---
--- Begin Message ---
Thanks for the update. I bet there were no cameras rolling to include THIS
footage in the show!
So the team was handed a less than ideal chassis, and a set of batteries
designed for a COMPLETELY different application, never been used to power
an EV before, can't even be charged without taking the car apart. Then
they are given a needlessly exhausting tight schedule that actually causes
lingering physical pain. There is no opportunity to do even a single
shakedown test run before the big day. Rich (and others?) spend their own
money (class act there, Jesse!) to fly down to prep the car, only to be
held at bay until they wrest away control of it from the painters at the
last minute in order to charge the batteries. (During the build, parts
magically appeared overnight and transmissions were rebuilt in hours. But
they couldn't get the paint job done in the past how many weeks?) So, once
again sleep deprived, the team is up at 4:30 am to reassemble the car for
the "challenge".
You know, a cynical person might almost think this was some kind of
deliberate sabotage. Is GM one of the MG sponsors?
Shari Prange
Electro Automotive POB 1113 Felton CA 95018-1113 Telephone 831-429-1989
http://www.electroauto.com [EMAIL PROTECTED]
Electric Car Conversion Kits * Components * Books * Videos * Since 1979
--- End Message ---
