EV Digest 4417
Topics covered in this issue include:
1) Re: Power of DC
by "Mark Hanson" <[EMAIL PROTECTED]>
2) Re: Pros and Cons of clutch-less?
by Victor Tikhonov <[EMAIL PROTECTED]>
3) Re: Pros and Cons of clutch-less?
by "Roy LeMeur" <[EMAIL PROTECTED]>
4) Re: Matching 2 motor set ups, was Re: Siamese Motors
by Ryan Stotts <[EMAIL PROTECTED]>
5) Re: Pros and Cons of clutch-less?
by Ryan Stotts <[EMAIL PROTECTED]>
6) RE: The Discovery EV program
by "Stu or Jan" <[EMAIL PROTECTED]>
7) Re: RS-232 isolators for E-meter, SIADIS, etc.
by Lee Hart <[EMAIL PROTECTED]>
8) RE: Another e-meter question...Lee?
by "Roger Stockton" <[EMAIL PROTECTED]>
9) Re: Pros and Cons of clutch-less?
by Victor Tikhonov <[EMAIL PROTECTED]>
10) RE: Pros and Cons of clutch-less?
by "ohnojoe" <[EMAIL PROTECTED]>
11) Re: Portland Visit
by John Wayland <[EMAIL PROTECTED]>
12) Re: Custom Emblems (for EVs)
by [EMAIL PROTECTED]
13) RE: Another e-meter question...Lee?
by "Roger Stockton" <[EMAIL PROTECTED]>
14) RE: Motor abuse? (was: RE: 9" Warp motor for drag racing)
by "Roger Stockton" <[EMAIL PROTECTED]>
15) Ranger on eBay
by Sherry Boschert <[EMAIL PROTECTED]>
16) RE: Another e-meter question...Lee?
by Otmar <[EMAIL PROTECTED]>
17) PowerPoints on EV
by Sherry Boschert <[EMAIL PROTECTED]>
18) Re: Portland Visit
by Victor Tikhonov <[EMAIL PROTECTED]>
19) Re: Pros and Cons of clutch-less?
by Michael Hurley <[EMAIL PROTECTED]>
20) Re: Another e-meter question...Lee?
by Victor Tikhonov <[EMAIL PROTECTED]>
21) RE: Another e-meter question...Lee?
by "Roger Stockton" <[EMAIL PROTECTED]>
22) Re: Pros and Cons of clutch-less?
by Victor Tikhonov <[EMAIL PROTECTED]>
23) RE: Another e-meter question...Lee?
by "Roger Stockton" <[EMAIL PROTECTED]>
24) Re: Pros and Cons of clutch-less?
by David Dymaxion <[EMAIL PROTECTED]>
25) Re: Another e-meter question...Lee?
by Victor Tikhonov <[EMAIL PROTECTED]>
26) Re: Pros and Cons of clutch-less?
by Victor Tikhonov <[EMAIL PROTECTED]>
27) Re: PowerPoints on EV
by Bob Siebert <[EMAIL PROTECTED]>
28) PT Cruiser conversion info (pics)
by Ryan Stotts <[EMAIL PROTECTED]>
29) RE: Pros and Cons of clutch-less?
by "Claudio Natoli" <[EMAIL PROTECTED]>
30) Re: Pros and Cons of clutch-less?
by David Dymaxion <[EMAIL PROTECTED]>
--- Begin Message ---
Check out www.hotels.com for Hagerstown, Md
----- Original Message -----
From: "Dave Cover" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, June 05, 2005 3:15 PM
Subject: Re: Power of DC
> >
> > See the Power of DC website for more details.
> >
> > Feel free to contact me for further information about the race.
> >
> > Chip Gribben
> > NEDRA Power of DC
> > http://www.powerofdc,com
> >
> I'm looking for information about cheap lodging in the area and the link
on the page doesn't work.
> Is there any camping in the area? On the grounds at the strip?
>
> Not sure if I can make it but I'm going to try.
>
> Thanks
>
> Dave Cover
>
--- End Message ---
--- Begin Message ---
You're right.
What should have said - if you take the same mass twice as far
(twice as big radius of a flywheel with the same
mass concentrated on the outer edge, it will take more
than twice torque to spin it (to the same RPM in the same time).
Of course, in practical terms heavier flywheel is just heavier,
not much bigger in diameter than a lighter one.
...
> If the car is in gear, the inertia of the
flywheel is swamped by the inertia of the car, so the flywheel mass and
inertia will only make a very slight difference in the necessary torque
to spin up the motor ( and, accelerate the car).
I think it makes sense to keep the clutch - just my opinion.
Try it on the first gear with high speed AC drive and you
may change your opinion :-)
Speaking from the first hand
experience, not just opinion. I had stock flywheel,
lightened stock flywheel and now - aluminum flywheel,
and I can compare.
Phil
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
Hi Victor
I fiqured you would probably respond to this. :^D
Victor Tikhonov wrote:
Roy, no problem, no flames.
Opinion with no data attached is, well, just an opinion.
Thanks for that :-)
Conversion without clutch makes good sense for specific
circumstances. It is always desired to reduce rotating mass
and the rate of RPM increase/decrease changes in 3rd power
with this mass (you'd need 8x of torque to spin up
to rhe same RPM in the same time a flywheel which is
only 2x as heavy).
Agreed
For a DC system which has safety issue with controller
die short and motors running at lower RPM, going
clutchless is indeed problematic solution.
Most conversions _are_ DC systems using the original transmissions and using
controllers with the possibility of "full-on" controller failure.
For AC systems capable of >10k RPM thus covering entire
range of speeds in one gear (as ACRX for example) and no
concerns about failing full on, going clutchless may make
perfect sense. Clutchless EV1 should be good example for you.
Or Solectria. Or Tzero.
Again... good or bad, most conversions remain DC with stock transmission.
Also, no clutch - no inertia of high rotating mass (yes,
the rotor is still there but only about as half
as the contributor) - easier to shift if you really
want/have to.
Some transmissions shift _much_ easier than others do without clutching.
To me, in addition to safety and ease of operation issues (I learned to
operate EVs in the mountains). The number one reason is when I am explaining
it to Joe Sixpak (potential EV owner) I prefer that he not start rolling on
the ground laughing when I tell him the conversion is done without a clutch
and retains the original transmission (with the exception of single-speed
and/or AC drive of course)
If the potential customer is already a dyed-in-the-wool motorhead to begin
with, he will laugh even harder.
Think about it.
.
Roy LeMeur
[EMAIL PROTECTED]
http://www.cloudelectric.com
http://www.dcelectricsupply.com
Cloud Electric Vehicles
19428 66th Ave So, Q-101
Kent, Washington 98032
phone: 425-251-6380
fax: 425-251-6381
Toll Free: 800-648-7716
My Electric Vehicle Pages:
http://www.angelfire.com/ca4/renewables/evpage.html
Informative Electric Vehicle Links:
http://www.angelfire.com/ca4/renewables/evlinks.html
EV Parts/Gone Postal Photo Galleries:
http://www.casadelgato.com/RoyLemeur/page01.htm
--- End Message ---
--- Begin Message ---
hi_torque_electric wrote:
> Whats D+D??
http://www.ddmotorsystems.com/
http://www.cloudelectric.com/category.html?UCIDs=1216492
--- End Message ---
--- Begin Message ---
Stefano Landi wrote:
>Could someone tell me very briefly or point to a good source as
> to the Pros and Cons and going clutch-less.
Take your current vehicle and drive it around and shift it without
using the clutch to see what it would be like.
The two drawbacks for me about having no clutch are:
If you plan on racing, you can't really effectively shift very fast.
The major thing that I hadn't thought about before that someone
pointed out the last time this was brought up: If for some reason the
controller/motor go full throttle, you won't be able to pull it out of
gear. Take your gas powered car and with the throttle wide open, try
and pull it out of gear...
You could get this company to make you an aluminum flywheel minus the
starter ring gear and also a light weight pressure plate.
http://www.specclutch.com/products.html
Or take your current flywheel and have the starter ring gear removed
and then have it rebalanced. Or just use a stock flywheel/pressure
plate setup as is. Or not.
Is there an off the shelf way currently available that you could use
for direct drive? Splined on one end and keyed on the other and is
the proper dimensions?
--- End Message ---
--- Begin Message ---
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Mark Hanson
Sent: Monday, June 06, 2005 4:14 PM
To: EV
Subject: Re: The Discovery EV program
Stu,
Hindsight is always 20/20
Mark
Mark,
Not so. If it were true, would anyone make the same mistake twice?
BoyntonStu
--- End Message ---
--- Begin Message ---
Victor Tikhonov wrote:
>
> Lee,
>
> Lee Hart wrote:
> > Victor Tikhonov wrote:
> >
> >>I hope you do you use ISO->RS232 converter!
> >
> > That reminds me. I just finished building yet another isolated RS-232
> > converter, to isolate an E-meter's RS-232 output so it can be connected
> > to a laptop or other non-isolated PC. This is probably the 5th or 6th
> > one I've made.
> ...
> > Basic specs:
> ...
>
> By all means do it if others have need for it.
> In this particular case:
>
> a) Richard has this converter as a part of his purchase, so "for free"
> b) iti s not simple RS232-isolator, it is ISOxxx(OBD2) <-> RS232
> converter/translator having L, K lines and other stuff not related
> to RS232.
>
> Just an isolator will not work with Simotion inverter.
>
> So I suppose your message/offer had nothing to do with
> SIADIS in subject or Richard's problem.
Ah; thank you for the clarification. I thought ISO was short for
"isolated", not one of the European ISO standards.
But the offer still stands. Does anyone need an isolated RS-232 to RS232
converter?
--
*BE* the change that you wish to see in the world.
-- Mahatma Ghandi
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Otmar [mailto:[EMAIL PROTECTED] wrote:
> 500 amps is the continuous rating, they can take much more than that
> for a short time.
Not if they are the standard Deltec MKB-500-50 shunts that typically
ship with E-Meters ;^>
500A is the full-scale rating, but Deltec's continuous rating is 2/3 of
that.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Roy LeMeur wrote:
For a DC system which has safety issue with controller
die short and motors running at lower RPM, going
clutchless is indeed problematic solution.
Most conversions _are_ DC systems using the original transmissions and
using controllers with the possibility of "full-on" controller failure.
Yes, we both and everyone else know this.
You said "going cluchless is a lame idea".
My only correction ws it may be a lame idea for DC drives.
You did not mention that, so the statement appeared
to apply for everything by default.
Or Solectria. Or Tzero.
Again... good or bad, most conversions remain DC with stock transmission.
I didn't realize your expression *only* applies to those
most of the conversions, not all conversions.
Some transmissions shift _much_ easier than others do without clutching.
The point was I can afford not to swith at all. In fact,
I don't. Most of people do. Few don't.
To me, in addition to safety and ease of operation issues (I learned to
operate EVs in the mountains). The number one reason is when I am
explaining it to Joe Sixpak (potential EV owner) I prefer that he not
start rolling on the ground laughing when I tell him the conversion is
done without a clutch and retains the original transmission (with the
exception of single-speed and/or AC drive of course)
Well, you wrote to the EVDL, not to joe sixpack. Thus my reply.
To the Joe I'd tell the same - "just in case keep the clutch".
If the potential customer is already a dyed-in-the-wool motorhead to
begin with, he will laugh even harder.
You mean laugh at his ignorance. His problem.
Think about it.
I did a lot, thus FAQ on my page clutch vs clutchless
guide for sixpacks.
Anyway, thanks for clarifying Roy.
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
Being a newbie and all and having recently driven both clutched and
cluthless. I like the clutch because you can (if you want)start out in a
lower gear and the shift are quicker, Hence it seems to go with the traffic
flow a little better.
I am sure it is a whole different story if you were talking to Clutch Cargo
and Paddle Foot
Have Fun
Joe
-----Original Message-----
From: Bill Dennis [mailto:[EMAIL PROTECTED]
Sent: Monday, June 06, 2005 10:16 AM
To: [email protected]
Subject: RE: Pros and Cons of clutch-less?
Stefano,
There's been lots of discussion about this on the EVDL in the past, so you
might find some good info searching the archives.
Here's a few links by someone who has done clutchless:
http://www.geocities.com/CapeCanaveral/Lab/4429/cl3.htm
Also, Bob Batson at EV-America.com does clutchless adapters and has a short
paper on his view of clutch vs. clutchless.
Bill Dennis
--- End Message ---
--- Begin Message ---
Hello to All,
Victor Tikhonov wrote:
> I can stop by if John doesn't mind.
>
> Any particular plans?
>
Victor, you know you're always welcome! Yes, I'm setting up a fun EVer's dinner
for
Sunday, probably around 6:00, probably Chinese or Mexican close by.
See Ya.....John Wayland
--- End Message ---
--- Begin Message ---
<<< I just stumbled on this while reading a blog. It's a company that
makes custom badges for cars. Yeah, I know the EV suppliers sell one
that says "Electric Vehicle" or whatever but this can be made to say
whatever you want.
http://www.youremblem.com/ >>>
Individual letters only go so far; how about these two for a custom look:
http://www.motorheadjewelry.com/customtg.html
http://www.emblemart.com/
--- End Message ---
--- Begin Message ---
Ryan Bohm [mailto:[EMAIL PROTECTED] wrote:
> >Think about it for a minute.
>
> Sometimes it's easier to just ask than think...I'm guilty.
Sorry; that came across testier than intended.
> I haven't been able to find anywhere that explicitly states
> that the e-meter for sale is a 1000 amp capable meter.
It does seem to be confusing.
EV Parts says to use a heavy duty 500A 50mV shunt (e.g. Deltec
D120-500-50) with the meter if you are interested in currents between
500-1000A.
<http://www.energyoutfitters.com/default.htm?http://www.energyoutfitters
.com/products/p_m_electronics/xantrex_link10.shtm>
Suggests that a 100mV 1000A shunt is the ticket for use with the Link-10
(as an alternative to the standard 50mV 500A shunt).
Xantrex's site only lists the Link-10 as available in either 'standard'
or 'choice' flavours, with 'choice' adding the RS232 and lift-lockout
options. Both are spec'd for up to 500A.
However, some places (e.g.
<http://www.solar4power.com/store/050-010-meters-xantrex.htm>) offer
'standard', 'choice', and 'deluxe' flavours, with the 'deluxe' flavour
being a 'choice' unit bundled with a 1000A shunt. The difference in
price between the 'choice' w/500A shunt and 'deluxe' with 1000A shunt
seems too great to just be due to the shunt itself, suggesting that the
'deluxe' really may have 1000A capability.
If, as Lee says, the 1000A software simply allows the meter to display
up to 1023A instead of saturating at 511A, while still using the same
500A/50mV (= 1000A/100mV) shunt, then perhaps Xantrex has simply taken
to shipping all meters with this software version and all that one needs
to do is to test their meter to see what its behaviour is when the shunt
provides it a signal in the 50-100mV range. If I were to try this, I'd
use a 50A/50mV shunt and run 50-100A through it to generate the current
signal rather than trying to generate a traction load in the 500-1000A
range with the stock shunt. Or, plunk on a resistor instead of a shunt
and use a variable power supply to feed a few mA through it; as you ramp
up the supply, the meter display should ramp up from 0 to 500, then as
you continue ramping it up the display will either saturate at 511 or
continue to 512 and beyond.
> I think my conclusion is to go with the 1000 amp 50mv shunt
> configuration, and deal with the math. My main reason for getting an
> e-meter is for integration with my digital dashboard gauges.
> A PIC will get the information from the e-meter, and translate that
> to the dashboard fuel gauge.
Unless you already have this shunt, you may want to test your meter to
see what it displays when the shunt signal is in the 50-100mV range. If
it doesn't saturate at 511 then you will want to use a 1000A/100mV (=
500A/50mV) shunt instead and the math will take care of itself.
As others have observed, you are unlikely to spend much time at all in
the 500-1000A range, relatively speaking, so you could likely just use
the stock 500A shunt and not worry about the meter pegging at 511A for a
few seconds here and there. The 1000A/50mV shunt would allow you to
measure currents in the 500-1000A range, though your PIC would have to
do the math to correct the readings. You might be able to set up the
meter's battery capacity and Peukert parameters such that the fuel guage
feature remains accurate without correction.
The big concern, as others have pointed out, is that you must not allow
the shunt to overheat or its accuracy will suffer. 140-145C seems to be
the level to stay below to keep the manganin elements happy. Deltec
(manufacturer of the stnadard MKB-series shunt used with most E-meters)
doesn't recommend their shunts be run continuously at more than 2/3 of
their rated maximum (i.e. 2/3 of 500A for the MKB-500-50 500A/50mV
shunt). Of course, the shunts come from the factory at +/-0.25%
accuracy and the E-Meter/Link-10 is spec'd for +/-0.8%, and let's face
it, you'd never know if it were off by even 2%, so it may be that even
if you did overheat the shunt it wouldn't cause you any grief.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Otmar [mailto:[EMAIL PROTECTED] wrote:
> At 1:11 PM -0700 6/1/05, Roger Stockton wrote:
>
> >As far as I know, even the
> >mighty 'Zilla does not (yet?) offer the ability to program such a
> >current limit profile; you can set a current limit, and a voltage
> >limit, but not something that varies.
>
> Actually you can get quite close to this by setting the battery
> current limit lower than the motor current limit. Doing that reduces
> the motor current limit as the duty cycle, and therefore the motor
> voltage, goes up.
Cool! Thanks for the insight, Otmar.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Anyone familiar with this Ford Ranger EV that's on
EBay?
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=4554143899&sspagename=STRK%3AMEWA%3AIT
One of our chapter members may be interested in it.
Would someone in LA area be willing to check it out
for him? This would be his first EV.
Please email him off-list at cdkennedy at aol.com, and
cc me too, if you don't mind.
Thanks,
Sherry Boschert
San Francisco Electric Vehicle Association
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
At 3:02 PM -0700 6/6/05, Roger Stockton wrote:
Otmar [mailto:[EMAIL PROTECTED] wrote:
500 amps is the continuous rating, they can take much more than that
for a short time.
Not if they are the standard Deltec MKB-500-50 shunts that typically
ship with E-Meters ;^>
500A is the full-scale rating, but Deltec's continuous rating is 2/3 of
that.
Cheers,
I stand corrected...
The folks at Deltec told me I didn't need to worry as long as the
element didn't discolor.
I appreciated the link to shunt info paper, but have not been able to
answer the most important question.
The paper said:
A shunt may operate safely up to 145 C.
Beyond that, the alloy it is made from--called manganin (which is a
material which has the unusual and desirable
property that it does not change resistance when it changes
temperature)--can undergo permanent changes of
resistance.
But how much does it change?
My motor shunt has purple in the center, and yet reads right along
with my DC clamp on meter when cold. But the clamp on meter is no
better than 1% accurate.
1% on a shunt is considered terrible, but in my EV 3% is plenty close
enough for motor current readings so long as its repeatable. (for
driving, not for controller calibration) So I wonder if some
overheating of a shunt is really a problem for most of us?
One shunt salesman told me that by the time I really damaged the
shunt, the solder would have melted out of it....
Who knows what's really true?
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
I have 43 PowerPoint slides that I put together for
the EV half of our workshop on Saturday -- "PV/EV =
Solar Power + Electric Vehicles." (Thanks to Bob Bath
and Marc Geller, from whom I copied a few slides.) If
anyone would like to see/use them, email me off list.
The file is too big to be posted in the Files sections
of any of the lists I subscribe to -- I tried.
And if you spot any mistakes, of course please let me know.
Sherry Boschert
President
San Francisco Electric Vehicle Association
415-681-7731
www.sfeva.org
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
Will be there. You're only 650 Wh away.
Victor
John Wayland wrote:
Hello to All,
Victor Tikhonov wrote:
I can stop by if John doesn't mind.
Any particular plans?
Victor, you know you're always welcome! Yes, I'm setting up a fun EVer's dinner
for
Sunday, probably around 6:00, probably Chinese or Mexican close by.
See Ya.....John Wayland
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
At 4:37 PM -0500 on 6/6/05, Ryan Stotts wrote:
The major thing that I hadn't thought about before that someone
pointed out the last time this was brought up: If for some reason the
controller/motor go full throttle, you won't be able to pull it out of
gear. Take your gas powered car and with the throttle wide open, try
and pull it out of gear...
This isn't necessarily the case. In my (still unfinished)
conversions, I pulled the clutch and intend to install a cutoff
attached to the handbrake. Pull the brake and the main pack relays
cut off. So to have a true fail-on situation, the controller, relays
and breaker would all have to simultaneously fail.
--
Auf wiedersehen!
______________________________________________________
"..Um..Something strange happened to me this morning."
"Was it a dream where you see yourself standing in sort
of Sun God robes on a pyramid with a thousand naked
women screaming and throwing little pickles at you?"
"..No."
"Why am I the only person that has that dream?"
-Real Genius
--- End Message ---
--- Begin Message ---
Otmar wrote:
I stand corrected...
The folks at Deltec told me I didn't need to worry as long as the
element didn't discolor.
...
Who knows what's really true?
Otmar, it is true that hot enough (discolored)
mangnaine element will not read correct (read higher)
than cold one. It reads wrong only *while hot*, e.g
beyond his pont response is no longer linear.
What he didn't
mention, as soon as it cools of, even though
discolored mark remains, resistance returns to
normal (provided you did not discolor as much
as needed to melt/deform the shape (crossection)
of the element). Discoloration you see is surface
oxydation as you see on any, say steel, object
in a torch flame. If the composition of the metal
didn't change and the length/crossection is still
the same, it will have the same resistance;
at least the difference will not be detectable with
simple EV instrumentation.
High end wire wound power resistors (and calibration
reference resistors) use this kind of wire material
so when it gets very hot, resistance does not drift
away too much.
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
Otmar [mailto:[EMAIL PROTECTED] wrote:
> I stand corrected...
Not something that happens everyday ;^>
> I appreciated the link to shunt info paper, but have not been able to
> answer the most important question.
>
> The paper said:
> >A shunt may operate safely up to 145 C.
> >Beyond that, the alloy it is made from--called manganin (which is a
> >material which has the unusual and desirable
> >property that it does not change resistance when it changes
> >temperature)--can undergo permanent changes of
> >resistance.
>
> But how much does it change?
> My motor shunt has purple in the center, and yet reads right along
> with my DC clamp on meter when cold. But the clamp on meter is no
> better than 1% accurate.
> 1% on a shunt is considered terrible, but in my EV 3% is plenty close
> enough for motor current readings so long as its repeatable. (for
> driving, not for controller calibration) So I wonder if some
> overheating of a shunt is really a problem for most of us?
Perhaps the graphs of TCR and TCR shift in this document may help?
<http://www.willow.co.uk/E_FHR2_3025_3818_4_4618_3825_3825H__edited_.pdf
>
> One shunt salesman told me that by the time I really damaged the
> shunt, the solder would have melted out of it....
I suspect that for our relatively crude measurement needs in EVs this is
pretty much the case. Most people have nothing to check/calibrate their
E-Meter to, and even if they did, how many people keep their instruments
calibrated so they know they are anywhere near even what the manual says
they are good for?
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Michael Hurley wrote:
This isn't necessarily the case. In my (still unfinished) conversions, I
pulled the clutch and intend to install a cutoff attached to the
handbrake. Pull the brake and the main pack relays cut off. So to have a
true fail-on situation, the controller, relays and breaker would all
have to simultaneously fail.
Imagine sitting waiting for green, Usually your bumper is 3-4 feet
away from the car in front of you. Sould your controller fail full on
at this time, calculate your reaction time to pull that hand brake.
If you lurch with squeaking tires toward pedestrian/child,
even few feet, you're in serious trouble even if you don't
quite reach them.
FOr that kind of reaction you should conatantly keep your hand
on the parking brake ready and *expect* to pool at any second.
No one normally drives that way.
Not to say your solution is bad - it is better than most people have.
But it has its serious limitations as well.
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
Victor Tikhonov [mailto:[EMAIL PROTECTED] wrote:
> Otmar, it is true that hot enough (discolored)
> mangnaine element will not read correct (read higher)
> than cold one. It reads wrong only *while hot*, e.g
> beyond his pont response is no longer linear.
> What he didn't
> mention, as soon as it cools of, even though
> discolored mark remains, resistance returns to
> normal (provided you did not discolor as much
> as needed to melt/deform the shape (crossection)
> of the element).
Unfortunately, this is incorrect. A *permanent* change in manganin resistance
elements can occur at temperatures over 30C:
"To minimize temperature effects, Manganin element resistors are usually
maintained in an oil bath at 25�C. [...] Manganin element resistors can be used
at temperatures other than 25�C by the application of temperature corrections.
The curve of a Manganin resistor can be accurately represented by a quadratic
equation containing unique alpha and beta values. These values, although
specific to an individual resistor, generally do not change over time as they
are inherent to the element. Temperature coefficients can be determined by
measuring a resistor's values at different temperatures and solving the
quadratic equation for its alpha and beta values. Manganin resistors are often
supplied with a table of corrections from 18� to 30�C. Above 30�C a resistor
can undergo a permanent shift in value.
Standard resistors should never be exposed to elevated
temperatures. For this reason, shipment in colder months or by air is
preferable to shipment in summer or by ground transport. Many labs hand carry
their standards to national labs for certification. Shock or extreme vibration
can cold work an element, altering its value. Appropriate care should be
exercised in the storage and transport of standard resistors."
(from <http://www.procinst.com/callabmagarticle.htm>), however, this is of
interest only with respect to resistances used as reference standards.
The shunt manufacturers warn of a permanent change in resistance if the shunt
is operated above 140-145C:
"Continuous operating current should not exceed 2/3 ammeter shunt rating. To
ensure proper operation the shunt temperature is in no way to exceed 145�C, as
a permanent change in resistance will occur." (from
<http://www.deltecco.com/resources.htm>).
It is likely that the permanent shift in value in either case is unimportant
for our crude EV applications, but it does still occur. Discolouration of the
manganin element almost certainly indicates the shunt has been hot enough to
undergo a permanent change in value.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Taking a pound off the flywheel is like taking about 3 pounds off the
car somewhere else for acceleration.
--- Victor Tikhonov <[EMAIL PROTECTED]> wrote:
> > If the car is in gear, the inertia of the
> > flywheel is swamped by the inertia of the car, so the flywheel
> mass and
> > inertia will only make a very slight difference in the necessary
> torque
> > to spin up the motor ( and, accelerate the car).
> >
> > I think it makes sense to keep the clutch - just my opinion.
>
> Try it on the first gear with high speed AC drive and you
> may change your opinion :-)
>
> Speaking from the first hand
> experience, not just opinion. I had stock flywheel,
> lightened stock flywheel and now - aluminum flywheel,
> and I can compare.
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--- Begin Message ---
Roger Stockton wrote:
Victor Tikhonov [mailto:[EMAIL PROTECTED] wrote:
...
What he didn't mention, as soon as it cools of, even though
discolored mark remains, resistance returns to normal (provided you
did not discolor as much as needed to melt/deform the shape
(crossection) of the element).
Unfortunately, this is incorrect.
...
A *permanent* change in manganin
resistance elements can occur at temperatures over 30C:
...
Above 30�C a resistor can undergo a permanent
shift in value.
Roger, I'm passing along what I've been told by people
dealing with these. Permanent damage relevant for
calibration quality (0.1% off) is unacceptable, but
for measurement is OK. If you want to dig to pure
physics, unfortunately what you have quoted becomes
incorrect either: *everything without exception*
around us changes property with temperature.
If what they wrote and you quoted is true,
then as soon as I take resistive element in my hand
which is around 36'C, it is already permanently
damaged. Ridiculous, isn't it?
On the atomic level - may be permanent change took place,
I'm not an expert. But you surely can ignore *that* kind
of change.
Cheers,
Victor
--- End Message ---
--- Begin Message ---
Depends on the gearing!
Victor
David Dymaxion wrote:
Taking a pound off the flywheel is like taking about 3 pounds off the
car somewhere else for acceleration.
--- End Message ---
--- Begin Message ---
Hello Sherry:
I would be interested in a few slides that plainly show the PV half.
Many thanks.
/Bob Siebert
On Jun 6, 2005, at 5:26 PM, Sherry Boschert wrote:
I have 43 PowerPoint slides that I put together for
the EV half of our workshop on Saturday -- "PV/EV =
Solar Power + Electric Vehicles." (Thanks to Bob Bath
and Marc Geller, from whom I copied a few slides.) If
anyone would like to see/use them, email me off list.
The file is too big to be posted in the Files sections
of any of the lists I subscribe to -- I tried.
And if you spot any mistakes, of course please let me know.
Sherry Boschert
President
San Francisco Electric Vehicle Association
415-681-7731
www.sfeva.org
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--- Begin Message ---
One of my Dad's friends just stopped by and had one has a rental. I
checked it out while it was here and he even let me drive it around a
bit. I think it would make a really nice conversion. Rides real
nice, quiet, lots of room up front.
I took a tape measure to it and got some quick measurements. Just
eyeballing it with a tape, it looks like from the edge of the bell
housing to the passenger frame rail, there is 20" to "21" in length
for the electric motor.
To get the ICE motor out, I'd unbolt the struts, exhaust, fuel lines,
coolant lines, battery cable(s), wires, steering column, and also the
various motor and trans axle mounts. Have the vehicle up on stout
jack stands and lower the whole engine/trans assemble down as 1 unit.
Possibly with both tires still connected to it all. Then roll it out
of there and install the electric motor.
Just by looking at the stock battery and imagining more of them spread
around the front; there MIGHT be room for up to 9 AGM's up front.
Maybe.. But that's really packing them in there. Consider the stock
battery is in the front corner driver side, and it looked like there
was space for 2 more between it and the master cylinder.
For batteries in the back, a quick and simple install could have them
mounted on the floor behind the backseat. If you wanted more
batteries, and you didn't mind losing the back seat, another row could
go there.
Another option would be to put them below the floor. Under the back
seat is the gas tank. Under the rear floor is the spare tire. Maybe
there could be two kits? One above the floor that consists of racks,
and one below the floor that is a drop in box that is either
welded/bolted/riveted in place?
Here's a pic of the door sticker with the GAWR weights for front/rear:
http://img2.uploadimages.net/238627door.jpg
A pic of the rear cargo area. About 40" to 41" across and ~27" length:
http://img2.uploadimages.net/984435floor.jpg
http://img2.uploadimages.net/089724floor1.jpg
The back seats fold forward and the floor is about 12" to 13" across
and about 40" wide:
http://img2.uploadimages.net/220769seat1.jpg
http://img2.uploadimages.net/217846seat2.jpg
If I would have had it longer, I could have gotten more pics of it.
---
This site claims the PT weighs ~3100 lbs. Just looking at the one
that was here, I don't know where all that weight is..:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38102/
Other 2005 cars and their weights for comparison / consideration:
Neon, ~2580 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38107/
Chevy Aveo, ~2350 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38088/
The Cavalier that's just been replaced by the Cobalt weighs ~2600
lbs(these cars are all over the place):
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38428/
Cobalt, ~2800 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38085/
Focus, ~2600 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38117/
Civic, ~2400 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38131/
Accord, ~3000 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38129/
Tiburon, ~2900 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38142/
Kia Rio, ~2400 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38159/
Kia Spectra, ~2700 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38162/
Mitsu Eclipse. ~2900 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38197/
Scion xA, ~2300 lbs, Scion xB, ~2400 lbs, Scion tC, ~2900 lbs:
http://auto.consumerguide.com/Search/index.cfm/type/new/make/1773/name/Scion/
Suzuki Aerio, ~2600 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38238/
Toyota Celica, ~2400 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38246/
Corolla, ~2500 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38247/
Echo,~2000 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38249/
Matrix, ~2680 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38253/
On that note, Pontiac Vibe, ~2700 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38219/
Prius, ~2900 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38254/
Beetle, ~2700 lbs:
http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/38262/
That's only 22 different cars(I feel it to be a conclusive list as far
as '05 models for lightweight EV use). Hard to believe there are so
many other car/truck models being made these days..
---
I agree, a conversion kit or three for more modern cars needs to be
made. I never, ever see a VW Rabbit on the streets around here. I
remember seeing them in the 1980's, but it's been years since I've
seen one here. Think about how many conversions HAVE been done with
that car just because there was a kit available for it. And those are
some premium priced racks and boxes too... Keep in mind that the
number one hinderence for most people is the up front conversion cost.
Prefab racks or boxes. If they are low cost or reasonable cost, the
conversion will be much less intimidating for others and the vehicle
can be converted in a much more timely fashion.
Racks that bolt right in, or boxes that drop right in.
Auto manufacturers could make lightweight cars if they wanted to.
They could make lower cost cars if they wanted too.
Shame there aren't any sub 2,000 pound cars being made anymore.
Of all those cars I listed, the ones in the 2000 lb range, not very
exciting or stand out very much. The PT would be something fresh in
the EV world at least...
I wonder if Chrysler would be willing to sell 10 or 20 of them brand
new sans motor, fuel, and exhaust systems, plus anything else related?
It would be neat to spec them out with choice options(all identical).
What would they each cost minus all that stuff? $2000/3000/4000? ;)
--- End Message ---
--- Begin Message ---
Victor Tikhonov writes:
> Imagine sitting waiting for green, Usually your bumper is 3-4 feet
> away from the car in front of you. Sould your controller fail full on
> at this time, calculate your reaction time to pull that hand brake.
>
> If you lurch with squeaking tires toward pedestrian/child,
> even few feet, you're in serious trouble even if you don't
> quite reach them.
>
> FOr that kind of reaction you should conatantly keep your hand
> on the parking brake ready and *expect* to pool at any second.
> No one normally drives that way.
Will the reaction time for an uncommanded, unexpected lurch really be
appreciably faster with a clutch?
Or are you suggesting that, in an EV with a clutch, one should sit at the
traffic lights with the clutch pedal depressed?
Cheers,
Claudio
--- End Message ---
--- Begin Message ---
Very true! Depending on the car, that's a good 2nd or 3rd gear
number. 1st gear is often traction limited, so it doesn't help as
much there.
--- Victor Tikhonov <[EMAIL PROTECTED]> wrote:
> Depends on the gearing!
>
> Victor
>
> David Dymaxion wrote:
>
> > Taking a pound off the flywheel is like taking about 3 pounds off
> the
> > car somewhere else for acceleration.
>
>
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--- End Message ---
