EV Digest 6735
Topics covered in this issue include:
1) Re: Linux EDA Dexign Software.
by Marcin Ciosek <[EMAIL PROTECTED]>
2) Re: Automatic or Manual?
by David Dymaxion <[EMAIL PROTECTED]>
3) Re: Rectactor Controller Suggestions
by Lee Hart <[EMAIL PROTECTED]>
4) Re: Linux EDA Dexign Software.
by "Martin Klingensmith" <[EMAIL PROTECTED]>
5) Re: Jay Leno no friend of electric cars.
by GWMobile <[EMAIL PROTECTED]>
6) Re: AC Questions - Just got my donor pickup!!!-
by Tehben Dean <[EMAIL PROTECTED]>
7) Beware Blems
by "Mark Hanson" <[EMAIL PROTECTED]>
8) Re: Mechanical PWM Was: Building your own, Commercial Contactor
by "Martin Klingensmith" <[EMAIL PROTECTED]>
9) Re: Automatic or Manual?
by "Marty Hewes" <[EMAIL PROTECTED]>
10) Re: AC Questions - Just got my donor pickup!!!-
by "Dmitri" <[EMAIL PROTECTED]>
11) Re: Jay Leno no friend of electric cars.
by Bill Dennis <[EMAIL PROTECTED]>
12) Re: Rectactor Controller Suggestions
by Chet Fields <[EMAIL PROTECTED]>
13) Re: Linux EDA Dexign Software.
by Danny Miller <[EMAIL PROTECTED]>
14) Re: Rectactor Controller Suggestions
by Chet Fields <[EMAIL PROTECTED]>
15) Re: FW: Jay Leno no friend of electric cars.
by GWMobile <[EMAIL PROTECTED]>
16) RE: article: ZAP (OTC BB: ZAAP) Reinvents the Wheel with Advanced
Electric Wheel Motor Technology Partner
by "Randy Burleson" <[EMAIL PROTECTED]>
17) RE: Automatic or Manual?
by "Randy Burleson" <[EMAIL PROTECTED]>
18) Re: Jay Leno no friend of electric cars.
by "David Roden" <[EMAIL PROTECTED]>
19) Re: Beware Blems
by "David Roden" <[EMAIL PROTECTED]>
20) RE: Automatic or Manual?
by "David Hankins" <[EMAIL PROTECTED]>
21) RE: Jay Leno no friend of electric cars.
by "Randy Burleson" <[EMAIL PROTECTED]>
22) Re: AGNS bike sets new NEDRA record
by Chip Gribben <[EMAIL PROTECTED]>
23) Re: Automatic or Manual?
by "Marty Hewes" <[EMAIL PROTECTED]>
--- Begin Message ---
Hi Jeff, Randy and John,
I see GNU software enthusiast even here, so here are my two (three) cents
about Linux EDA software:
Oregano, GTK/Gnome based software:
http://arrakis.gforge.lug.fi.uba.ar/
you can enrich its functionality by adding
ngSpiece (http://ngspice.sourceforge.net/) or
GNU Cap (http://www.gnu.org/software/gnucap/)
for circuit simulation,
kiCAD:
http://www.lis.inpg.fr/realise_au_lis/kicad/
KTech (QT/KDE based):
http://sourceforge.net/projects/ktechlab
Of course there are more, a lot more good software but everyone got its
favorite.
In case you have question about GNU software, I'll be happy to help.
Marcin
--- End Message ---
--- Begin Message ---
I think a couple things can be clarified:
In an ICE, you can rev up the motor, dump the clutch, and spin the wheels, but
still be overgeared. I suppose you could do that in an EV, too, but generally a
single gear EV is direct drive. You can't rev up and dump the clutch. If you
can spin the wheels from a standstill, gearing lower will not make you
accelerate any faster -- you already have enough torque at the wheels to
overwhelm them.
For max acceleration, you should not shift at the point of going out of current
limit, you should go a little further. Generally, up shifting lowers your
gearing mechanical advantage to about 2/3 of the gear before. So you should
keep accelerating until the torque drops to about 2/3 of the current limit
torque, and then shift. This assumes you have a series DC system where the
torque drops off fairly fast past current limit.
For an AC or sepex motor, once out of current limit you are theoretically in a
constant power mode. Even though the torque is dropping, it is dropping slowly
enough (as 1/rpm) that it is fastest to rev to redline before shifting. In
reality, efficiency curves, different gears' efficiencies, etc. means you'd
have to experiment a bit to find the optimal shift point.
----- Original Message ----
From: Marty Hewes <[EMAIL PROTECTED]>
To: ev@listproc.sjsu.edu
Sent: Thursday, May 3, 2007 11:48:34 PM
Subject: Re: Automatic or Manual?
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, May 03, 2007 10:30 PM
Subject: Re: Automatic or Manual?
> From: Marty Hewes <[EMAIL PROTECTED]>
>> I think the trans/no trans tradeoff might change significantly
>> depending on performance expectations.
>
> It's not really an acceleration performance issue. Once you have enough
> motor current to spin the tires in the one-and-only gear a
> transmissionless EV has, there is no point to other lower gear ratios. The
> battery current will be the same.
Until the tires hook up, and the motor RPM drops to the point you're not
generating much horsepower because the RPM is too low.
If I'm reading these motor specifications correctly, torque is directly
related to current. Power is directly related to both torque and RPM. If
you are operating at the current limit of the controller, a constant
current, and therefore a constant torque, then the more the RPM rises, the
more power you make. That continues up until the motor's effective
impedence (due to back EMF) rises to the point where the controller
increases the motor voltage to the pack voltage and can no longer maintain
the current. Then you shift, unless you are in top gear.
...
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
Chet Fields wrote:
> After following the latest contactor controller thread with great
> interest, I am seriously considering building my own. I have come up
> with the following based on the rectactor schematics referred to in
> the previous links and my particular needs. I have 18 6V flooded
> lead acid batteries (Trojan TE-35). I was thinking of dividing them
> up into 18V _modules_ and connecting them this way: (View with fixed
> font, Sorry my diodes don't look better. I did the best I could ;)
>
> S1 S3 S5 S7 S9
> / / / / /
> -----/ --------/ --------/ --------/ --------/ ---------------- M+
> | / | / | / | / | / |
> | D1 / | D2 / | D3 / | D4 / | D5 / |
> --- / --- / --- / --- / --- / ---
> - _\/ - _\/ - _\/ - _\/ - _\/ -
> --- \|\ --- \|\ --- \|\ --- \|\ --- \|\ --- R1
> - / - / - / - / - / - --/\/\/--
> | / | / | / | / | / | | |
> |/ / |/ / |/ / |/ / |/ / | | / |
> ----/ --------/ --------/ --------/ --------/ ----------/ -----
M- S2 S4 S6 S8 S10 S11
You did very well! 'Taint purty, but it clearly explains the circuit,
which is the whole point.
Clear enough to see that there's a problem. You have the diodes pointing
up (as I tried to clarify in the above illustration). This is the
rectactor circuit for *charging* the batteries -- not for drawing
current from them.
The rectactor circuit for *loading* the batteries has two diodes and one
SPST contactor per stage. Like this:
_______________B+
| |
_|_ D1 __|__+
/_\ ___ 18v
| S1 / | -
|____/ ____|
| |
__|__+ _|_
___ 18v /_\ D2
| - |
|__________|____B-
With S1 open, the batteries are in parallel -- you get 17v between B+
and B-. Each has a diode in series, so you lose about 1v (silicon) or
0.5v (schottky). You can load the parallel batteries (draw current from
them to run a motor), but can't do regen or charge them in parallel
(because the diodes block reverse current flow).
With S1 closed, the batteries are in series -- you get 36v between B+
and B-. The diodes are out of the circuit. You can both load and charge
the batteries in series.
This is the basic building block you use to produce larger arrays. Treat
B+ and B- as the two terminals of a "battery" that has two switchable
voltages.
With 4 groups of batteries, it would look like this:
_______________M+
| __|__
_|_ D5 | B+ | 18/36v module #1
/_\ |_____| (2 18v batteries, D1, D2 S1)
| S3 / |B-
|____/ ____|
__|__ |
| B+ | _|_
|_____| /_\ D6
|B- |
|__________|____M-
This in turn could be used as the building block for even more
series/parallel circuits. This setup can give you any final voltage that
is a multiple of the basic module voltage. If each module is 18v and you
have four of them, you can get 18v, 36v, 54v, or 72v.
This works best with a number of modules that is a power of 2 (2, 4, 8,
16, 32...). Your 18-battery setup would require something a little more
awkward. If wired for 18v, you'd have six 18v modules. You could wire
them in three 18v/36v blocks as above. Then wire these blocks like this:
__________________________________M+
_|_ _|_ _|_
/_\ Da /_\ Db /_\ Dc
| _______| _______|
__|__ | __|__ | __|__
| B+ | | | B+ | | | B+ | 6-battery
|_____| / |_____| / |_____| 18v/36v modules
|B- | Sa |B- | Sb |B-
|_____| |_____| |
_|_ _|_ _|_
/_\ Dd /_\ De /_\ Df
|_____________|_____________|______M-
The three 6-battery modules can be switched between 18v and 36v. These
in turn can be connected in series or parallel by Sa and Sb above. The
circuit is more awkward because you need *two* diodes in series with the
center leg (diodes Db and De). This in turn forces you to have extra
diodes Da and Df just to balance the voltage drops, so all batteries
share the load current equally.
> I was hoping that I could get a bit more specific advice in regards
> to which components would be appropriate for this arrangement. I was
> thinking of the LEV200.
What is this the number for? A contactor? A diode?
> I would like to be good for about 400 amps max for under 10 second
> bursts and the rest of the time under 200 amps and more than likely
> around 100 amps continuous.
Sizing the parts requires that you first decide what current and voltage
each part must withstand. In a contactor controller, nothing but
operator common sense limits the peak current (unless you add some sort
of current sensing and automatic limiting). The simplest form of current
limiting is to put fuses or circuit breakers in series with each 18v
battery string. This also prevents trouble if a diode shorts or a
contactor welds.
Diodes and contactors both have peak and average current ratings. Pick
your fuses to set these limits. Every fuse has its own typical
current-versus-time curves, which you can find on the fuse
manufacturer's data sheet. For example, an inexpensive Bussman type NON
100 amp 250vac/125vdc general-purpose fuse can carry:
100 amps for 1 hour
140 amps for 5 minutes
250 amps for 10 seconds
600 amps for 1 second
2000 amps for 0.1 second
An Albright SW80 contactor's current-versus-time curve is
100 amps continuous
150 amps for 15 minutes
250 amps for 3 minutes
600 amps for 10 seconds
A 1N3736 200v 250a diode is rated:
100 amps at 70 deg.C case temperature
250 amps at 140 deg.C case temperature
4000 amps peak for 0.1 second
So this fuse would protect this contactor and diode (i.e. the fuse is
likely to blow before the contactor or diode fail). You just have to go
through the data sheets for the parts you pick to see what it takes.
> I was thinking that after the 8th step I would have field weakening
> through some variable resistor. Or should I have the field weakening
> on every step?
You only need field weakening when you need to raise motor rpm and
current, and can't do it by raising voltage because you're already on
the highest voltage step.
> Is there a particular type [of contactor] that would have 2 sets
> of contacts actuated at the same time?
Yes, they make them with almost any imaginable number of poles. 2-pole
and 3-pole are fairly common.
> Is the current actually increasing towards the right?
No. The current is the same everywhere in any given series path. When
you have the current splitting between parallel paths, it splits
(roughly) equally between them (assuming the same part types, same size
wire, etc.).
For example, in a single rectactor (my first circuit): In series, at 100
motor amps, both batteries and the switch are carrying 100 amps. In
parallel, at 100 motor amps, each battery and diode carry 50 amps.
This is where you get your current multiplication. With your 18 6v
batteries, wired as 3 batteries per module (18v groups), and the various
series/parallel steps:
18v step: 100a per battery, motor gets 18v @ 600a
36v step: 100a per battery, motor gets 36v @ 300a
54v step: 100a per battery, motor gets 54v @ 200a
108v step: 100a per battery, motor gets 108v @ 100a
> Could you use less expensive lower rated contactors for the lower
> numbered ones?
Yes. This is an advantage of contactor controllers. Properly arranged,
no single contactor ever sees the total voltage. Many of them see only a
small fraction of the total.
> How much voltage is across the contacts in the different
> series/parallel configurations? Do you look at how much voltage
> is there when they are open? I would assume so as there is very
> little voltage drop when they are closed.
You have to analyze the circuit to see what voltage is across each diode
and contact when they are not conducting. Or, build a little breadboard
and measure it (and scale up accordingly).
> And what value and type of resistor and diodes should be used?
This all depends on the current and voltage you need for your motor.
A reasonable guess for the starting resistor current is around 250 amps.
Most of these resistors are a big open coil of nichrome wire, so it's
not hard to experiment; get one a bit bigger than you need, and tap
along it to find the resistance that gives you a normal acceleration
from a dead stop.
Sizing the diode is harder. The time it can take any given current
depends on the heatsink, and that is something you supply. Crudely
speaking, if the case gets too hot to touch, you ran too much current
for too long.
> Finally, if I wanted regen (I do have a SepEx motor), could I only
> get it at 18V?
With your circuit, you can arrange the pack voltage to any step for
regen -- but not for motoring.
With my circuit, you can arrange the pack for any step for motoring, but
only the max voltage step allows regen.
If you use contactors in all locations, both are possible. In general,
armature voltage is proportional to rpm, for either motoring or
generating. So if you want regen down to low rpm, you'll need to
configure the pack for a low armature voltage.
--
Ring the bells that still 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, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Eagle (cadsoft.de) has the best price point in my mind, for both Linux
and Windows.
Unfortunately it's not free, but it's a complete package and you don't
have to spend weeks trying to figure out how to use it. There is a
free version which will do small boards. Output is gerber or any
number of vendor specific plotters, or EPS.
--
Martin K
On 5/4/07, Jeff Shanab <[EMAIL PROTECTED]> wrote:
I have no interest in starting any OS wars here, just some info for
those wanting to design circuit baords in the *nix environment.
Geda
http://www.geda.seul.org/
The gschem program seems a bit odd, not as user friendly but man it is
efficient and powerfull. It takes the sammy hagar touch: 1 hand on the
mouse 1 hand on the keyboard.
It is a suite of tools. There are a bunch of others but Geda seems to be
the most capable if a little odd.
--- End Message ---
--- Begin Message ---
Where did you get the jay leno quote and what quote do you have on his
steam car?
On Fri, 4 May 2007 9:28 am, Lawrence Rhodes wrote:
I'm not too bullish on electric cars as the way of the future. Modern
electric cars go roughly 100 miles on a charge, about the same as my
Baker;
so I don't see much progress there. I think electricity is a great
power
source for a car. But the problem is, how do you get it?
Thomas Edison invented the alkaline battery. My Baker still has some
original alkaline batteries. These have lead plates and use acid; we
wash
them out and refill them regularly and I'll use them indefinitely. But
even
Edison realized the future of the automobile was elsewhere. Legend has
it
that back in 1896, at a dinner party, he passed a note to his friend
Henry
Ford. Essentially it said, "The electric car is dead."
How prophetic was that?
I can't believe Jay Leno (the ultimate car geek) compares a Baker
Electric
to a Rav4 EV. They may have the same range but not the same speed or
convienences. I'm sure he's taken a ride in a Tzero or Tesla. He at
times
acts like a spokesman for GM & then crows the 0 emmissions standard of
his
steam car. He is so contrary sometimes I just don't understand his
agenda.
Lawrence Rhodes....
www.GlobalBoiling.com for daily images about hurricanes, globalwarming
and the melting poles.
www.ElectricQuakes.com daily solar and earthquake images.
--- End Message ---
--- Begin Message ---
Could some other people comment on Victor's systems?
Also here are the specs for the v6 that is in the pickup right now:
150 hp (112 kW) at 4800 rpm
180 ft·lbf (244 N·m) of torque at 3600 rpm
I would like to match or exceed this with the electric drive system.
So what size motor would be recommended?
Tehben Dean wrote:
Hey all,
I just got a 1990 4x4 toyota pickup to convert and have some
questions about what setup to use.
Soo what do you all think about this?
Does it sound like the AC55 will be a good fit?
Where do you live (hot or cold climate)? Make sure you have ability
to adequate cool off your motor if you load it for more-less
extended periods of time.
It gets up to 70ºF in the summer ;)
Solectria is no longer in existence, it's been sold to
Azure dynamics years ago. Make sure DMOC445 will be well supported:
this design, copied from BRUSA who is no longer producing
it (close to 10 years by now) is very old. Not that it's bad,
but documentation may be scarce.
Is there a better AC system available?
There are, but I'll let other to comment as I may appear biased
(since my company sells them).
Any comments and suggestions will be great :)
Compare at least with offers on metricmind.com site and make your
choice. FYI, I only carry liquid cooled drive systems.
Thanks,
Tehben
--
Victor
'91 ACRX - something different
Tehben
--- End Message ---
--- Begin Message ---
Hi,
An Interstate battery guy here in Roanoke, VA was selling "blems" that were
nothing more than someone elses dead batteries. He gets a bunch of dead
floodees back from the local golf courses and weeds out with a battery
checker the one's that still have some life in them, cleans them and resells
for 1/2 price of a new one. I think the blems that were being discussed are
in the same catagory.
BTW, I'll be at the LA,Cal www.awea.org Wind Expo June 3-7th if anyone wants
to meet there.
Have a renewable energy day,
Mark
_________________________________________________________________
Watch free concerts with Pink, Rod Stewart, Oasis and more. Visit MSN In
Concert today. http://music.msn.com/presents?icid=ncmsnpresentstagline
--- End Message ---
--- Begin Message ---
On 5/4/07, Tim Humphrey <[EMAIL PROTECTED]> wrote:
Maybe I'm being naive, but I would assume arc suppression to be rather simple.
In fact I'm suprised that Bob came up with a rectactor but didn't hit on the
solution for arc suppression.
I'm not going to reveal what it is that I think would work, yet. First I want
those thinking about this to see if they come up with the same thought.
Research, and Think about what an electronic controller (EC) uses to prevent
"arcing" from destroying the FET's the first time they shut off. A
contactor/rectactor/drum/rotating-brush controller doesn't require this device, but an EC
would immediately die without one.
Please.. Roger, Lee, Rod, Rich and others who have designed controllers let
"them" think about this one for a while. Feel free to email me offlist to
explain why it won't work though!!
--
Stay Charged!
Hump
I-5, Blossvale NY
Anything that "chops" voltage to an inductive load needs freewheel
diodes if you want it to survive!
--
Martin Klingensmith
--- End Message ---
--- Begin Message ---
Hi George,
Thanks for the comments.
----- Original Message -----
From: "George Swartz" <[EMAIL PROTECTED]>
Best way to approach gear box/motor selection is to have
motor "characteristic" curves. These are a family of curves showing
tractive effort(TE) versus RPM, voltage, and field weakening. On a series
motor, you will notice that the TE drops off rapidly above base speed, on
an
approximate constant horsepower curve.
That makes sense, because horsepower is a product of torque and RPM, and (I
assume) tractive effort is a function of torque. Since constant horsepower
means constant wattage, which also means constant battery current, that
means you're trading torque for RPM to keep the battery draw the same. I'm
coming at it from the other direction. I'm starting with a SWAG at how much
wattage is required to achieve a given acceleration at a given speed
(regardless of whether we're drag racing or just trying to get on the
expressway), and then determining what motor voltage and current provides
that wattage for the least money based on getting the motor RPM right. I'm
assuming acceleration is determined by wattage available beyond what's
needed to sustain current speed. The result is the same conclusion, that
there is a sweet spot where motor RPM is coming up, so the voltage is coming
up (more watts), but the back EMF hasn't killed the current draw yet (less
watts). If the goal is acceleration at least expense, IMHO you've got to
use gearing to stay in the sweet spot, and then size the controller and
batteries according to the need for acceleration and vehicle weight. Using
less gear reduction tips the scale toward low RPM and high torque to get the
same acceleration, which requires higher controller current, which is
expensive.
You will determine that even though
a particular motor can go to a high RPM, there is insufficient TE to
overcome wind resistance or grade. That is why gear shifting or field
weakening is required to move the motor back down on its TE curve where
more
torque is available.
Agreed, assuming you've hit the point where motor voltage equals battery
pack voltage, and current is dropping due to back EMF. If only these motors
had field windings that could be altered based on RPM. Maybe a twin winding
that could be switched from series to parallel. Wouldn't that essentially
equal a trans shift?
The equations for forces resistant to motion are simple, and probably
available in software, does anyone know? The motor curves are published
by
the motor manufacturer. The problem here, is that a manufacturer does not
rate a 36v motor to be run on 96v, for example, or to 4x rated current, so
a
little extrapolation may be needed.
Yeah, I've been using a few Advance and NetGain graphs, and none of them go
to where people are pushing these things. But I believe there are some rules
that make extrapolation possible. Apparently torque is directly related to
amps, and motor RPM is directly related to volts. Horsepower is directly
related to watts. So you can scale the graphs, although the results won't
be perfect because efficiency varies a bit. What you don't know from
extrapolation is at what point windings melt or brushes arc, so I'm assuming
taking either voltage or current too much past the graph isn't a good idea.
Marty
--- End Message ---
--- Begin Message ---
You might need to go with a DC system for that. AC systems with 150+ HP
don't look cheap.
----- Original Message -----
From: "Tehben Dean" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Friday, May 04, 2007 1:40 PM
Subject: Re: AC Questions - Just got my donor pickup!!!-
Could some other people comment on Victor's systems?
Also here are the specs for the v6 that is in the pickup right now:
150 hp (112 kW) at 4800 rpm
180 ft·lbf (244 N·m) of torque at 3600 rpm
I would like to match or exceed this with the electric drive system.
So what size motor would be recommended?
Tehben Dean wrote:
Hey all,
I just got a 1990 4x4 toyota pickup to convert and have some questions
about what setup to use.
Soo what do you all think about this?
Does it sound like the AC55 will be a good fit?
Where do you live (hot or cold climate)? Make sure you have ability to
adequate cool off your motor if you load it for more-less
extended periods of time.
It gets up to 70ºF in the summer ;)
Solectria is no longer in existence, it's been sold to
Azure dynamics years ago. Make sure DMOC445 will be well supported:
this design, copied from BRUSA who is no longer producing
it (close to 10 years by now) is very old. Not that it's bad,
but documentation may be scarce.
Is there a better AC system available?
There are, but I'll let other to comment as I may appear biased
(since my company sells them).
Any comments and suggestions will be great :)
Compare at least with offers on metricmind.com site and make your
choice. FYI, I only carry liquid cooled drive systems.
Thanks,
Tehben
--
Victor
'91 ACRX - something different
Tehben
--- End Message ---
--- Begin Message ---
It's from an article that Jay wrote for this month's Popular Mechanics.
Bill Dennis
GWMobile wrote:
Where did you get the jay leno quote and what quote do you have on his
steam car?
--- End Message ---
--- Begin Message ---
Thanks Lee! That's exactly what I was looking for. Much better arrangement with
2 Diodes and 1
contactor per block and I can build up using those blocks. I also like the fact
that I can get
regen at full voltage if I want.
Another question in regards to the AW80 contactor. Would it work for me? As
long as I watched the
amp draws carefully? I guess I am more worried about the voltage. The LEV200 is
a newer Kilovac
contactor. Around $60 I think. Not sure where to get them though. 12-900VDC and
500Amps. Would
that be better?
Thanks again,
Chet
--- Lee Hart <[EMAIL PROTECTED]> wrote:
> The rectactor circuit for *loading* the batteries has two diodes and one
> SPST contactor per stage. Like this:
>
> _______________B+
> | |
> _|_ D1 __|__+
> /_\ ___ 18v
> | S1 / | -
> |____/ ____|
> | |
> __|__+ _|_
> ___ 18v /_\ D2
> | - |
> |__________|____B-
>
> This is the basic building block you use to produce larger arrays. Treat
> B+ and B- as the two terminals of a "battery" that has two switchable
> voltages.
>
> > I was hoping that I could get a bit more specific advice in regards
> > to which components would be appropriate for this arrangement. I was
> > thinking of the LEV200.
____________________________________________________________________________________
Finding fabulous fares is fun.
Let Yahoo! FareChase search your favorite travel sites to find flight and hotel
bargains.
http://farechase.yahoo.com/promo-generic-14795097
--- End Message ---
--- Begin Message ---
Yeah Eagle's a good one. They have a pretty good Autorouter and that
gets to be indispensible. Once you have over a hundred wires and want
to move stuff around at will, autorouting is essential because it may
take days to rework the traces manually.
Danny
Martin Klingensmith wrote:
Eagle (cadsoft.de) has the best price point in my mind, for both Linux
and Windows.
Unfortunately it's not free, but it's a complete package and you don't
have to spend weeks trying to figure out how to use it. There is a
free version which will do small boards. Output is gerber or any
number of vendor specific plotters, or EPS.
--
Martin K
On 5/4/07, Jeff Shanab <[EMAIL PROTECTED]> wrote:
I have no interest in starting any OS wars here, just some info for
those wanting to design circuit baords in the *nix environment.
Geda
http://www.geda.seul.org/
The gschem program seems a bit odd, not as user friendly but man it is
efficient and powerfull. It takes the sammy hagar touch: 1 hand on the
mouse 1 hand on the keyboard.
It is a suite of tools. There are a bunch of others but Geda seems to be
the most capable if a little odd.
--- End Message ---
--- Begin Message ---
Oh, and thanks also for the point about the difference between motoring and
charging.
So to use my current charger at full pack voltage I would also need to have a
'charge' setting and
have the contactors engaged before charging. Hadn't thought of that.
One more reason I tip my hat to y'all and thank you again.
Chet
--- Lee Hart <[EMAIL PROTECTED]> wrote:
> Clear enough to see that there's a problem. You have the diodes pointing
> up (as I tried to clarify in the above illustration). This is the
> rectactor circuit for *charging* the batteries -- not for drawing
> current from them.
> With S1 closed, the batteries are in series -- you get 36v between B+
> and B-. The diodes are out of the circuit. You can both load and charge
> the batteries in series.
> With my circuit, you can arrange the pack for any step for motoring, but
> only the max voltage step allows regen.
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
What do you mean new?
Don't all alkaline batteries use acid electrolyte?
On Fri, 4 May 2007 9:58 am, George Swartz wrote:
Well, this is a new one: Alkaline battery that uses acid electrolyte.
Some
instantaneous high energy there!
On Fri, 4 May 2007 10:29:22 -0600, Tim Humphrey wrote
His agenda is really pretty simple.... Ratings!
But this is kin to political so, 'nuff said.
>
> -----Original Message-----
> From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On
> Behalf Of Lawrence Rhodes
> Sent: Friday, May 04, 2007 12:22 PM
> To: Electric Vehicle Discussion List;
> [EMAIL PROTECTED]; ETList; SFEVA;
> [EMAIL PROTECTED]; [EMAIL PROTECTED];
[EMAIL PROTECTED]
> Subject: Jay Leno no friend of electric cars.
>
> I'm not too bullish on electric cars as the way of the future.
Modern
> electric cars go roughly 100 miles on a charge, about the same as my
> Baker;
> so I don't see much progress there. I think electricity is a great
power
> source for a car. But the problem is, how do you get it?
>
> Thomas Edison invented the alkaline battery. My Baker still has some
> original alkaline batteries. These have lead plates and use acid;
we wash
> them out and refill them regularly and I'll use them indefinitely.
But
> even
> Edison realized the future of the automobile was elsewhere. Legend
has it
> that back in 1896, at a dinner party, he passed a note to his friend
Henry
> Ford. Essentially it said, "The electric car is dead."
>
> How prophetic was that?
>
>
> I can't believe Jay Leno (the ultimate car geek) compares a Baker
Electric
> to a Rav4 EV. They may have the same range but not the same speed
or
> convienences. I'm sure he's taken a ride in a Tzero or Tesla. He
at
> times
> acts like a spokesman for GM & then crows the 0 emmissions standard
of
his
> steam car. He is so contrary sometimes I just don't understand his
> agenda.
> Lawrence Rhodes....
--
Stay Charged!
Hump
I-5, Blossvale NY
www.GlobalBoiling.com for daily images about hurricanes, globalwarming
and the melting poles.
www.ElectricQuakes.com daily solar and earthquake images.
--- End Message ---
--- Begin Message ---
> It's probably 90,000 EVs and includes bikes and those
> little electric razor scooters.
Just FWIW, bikes and scooters are the primary forms of transportation in
many less car-centric societies. My travels really brought home to me
how weird we are with cars in the States.
Don't count ZAP out for smaller-scale solutions.
...but certainly take whatever they say with a HEALTHY grain of salt.
Randii (enjoys weird)
--- End Message ---
--- Begin Message ---
> If yo do decide to go with the single motor, your best stategy for
> climbing hill is to do it as fast as possible to limit the amount
> of time the motor sees the high amps.
Additionally, it may help to 'plan ahead' and come in with as much
momentum as possible. This is a way to sneak around a common EV
shortcoming, but at one end of the spectrum, semi trucks do the same
thing pushing 80K pounds up a hill with 350 horsepower and 1450 ft-lbs
of torque. The difference is they have the torque and gearing to get up
the hill one way or another... some EVs do not, without stops to cool
(and charge!).
Randii
--- End Message ---
--- Begin Message ---
On 4 May 2007 at 9:22, Lawrence Rhodes wrote:
> My Baker still has some
> original alkaline batteries. These have lead plates and use acid; we
> wash them out and refill them regularly and I'll use them indefinitely.
I'm assuming you're quoting Leno in this post - nowhere do you have
quotation marks or indicate where the quotation comes from. But whomever is
speaking, the above statement pretty well destroys his credibility.
David Roden - Akron, Ohio, USA
EV List Administrator
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--- End Message ---
--- Begin Message ---
On 4 May 2007 at 12:43, Mark Hanson wrote:
> An Interstate battery guy here in Roanoke, VA was selling "blems" that were
> nothing more than someone elses dead batteries.
Reminds me of one of my local battery dealers. He does a big trade in
"reconditioned" SLI batteries for ICEVs. His shop is in one of the lower-
income regions of Akron. For 20 bucks he'll get your big old '76 Buick
going again. He sells a lot of them.
One day I was there to buy some (new) product and watched one of these
transactions take place. After the customer had left, I asked the guy
helping me load my car, "So exactly how DO you recondition a battery?"
He didn't even look up. "We charge it," he replied.
When buying batteries, make sure you know what you're really getting!
David Roden - Akron, Ohio, USA
EV List Administrator
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Want to unsubscribe, stop the EV list mail while you're on vacation,
or switch to digest mode? See how: http://www.evdl.org/help/
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Note: mail sent to "evpost" or "etpost" addresses will not reach me.
To send a private message, please obtain my email address from
the webpage http://www.evdl.org/help/ .
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--- End Message ---
--- Begin Message ---
A flywheel can be made "light" for EV use as you don't need the outer Gear
ring for the starter and you don't need all that mass to keep the motor
running smoothly at idle or to keep you from stalling the motor at low rpms.
So, you can machine off the outer diameter down to only the area needed for
the clutch. The thickness can be reduced and any additional material not
required for structural integrity can be removed with further machining and
drilling.
David
-----Original Message-----
From: Marty Hewes [mailto:[EMAIL PROTECTED]
Sent: Thursday, May 03, 2007 6:29 AM
To: ev@listproc.sjsu.edu
Subject: Re: Automatic or Manual?
Regarding efficiency, I suspect the most efficient, and lightest, would be a
manual without clutch or flywheel, with thin gear lube, that is geared so
that it is running straight through most of the time. Of course everyone
who drives the car would have to be able to drive stick without a clutch.
I'm guessing that a properly done automatic without a flywheel or torque
converter won't be too far behind, and will have less learning curve,
although getting it to work right will take some work. Personally, I
suspect an automatic with no flywheel or converter will be pretty close to
the same efficiency as a manual with flywheel and clutch in stop and go city
driving, since you're not wasting energy spinning up all that rotational
mass. But it's not simple.
Dual motors and no gearbox sounds interesting, but launching without gear
reduction sounds like it would take a lot of current and be tough on the
batteries to me, but I haven't tried it.
Marty
----- Original Message -----
From: "Bob Bath" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, May 03, 2007 6:51 AM
Subject: Re: Automatic or Manual?
Most people do manuals. Automatics are too
inefficient.
Your '83 won't have as much capacity for batteries as
newer models, but if you're looking for something for
in-town, low speeds, it should be fine.
--- [EMAIL PROTECTED] wrote:
--- End Message ---
--- Begin Message ---
He's a car guy -- a mechanized enthusiast -- a gearhead.
Does he need to have an agenda beyond that?
Be happy that he restored, displays, and uses a Baker.
Either don't sweat the rest, or start calling and getting him rides in
local EVs. Better yet, challenge him to a race -- he's a gearhead, and
we're pretty easy to tempt that way.
Randii
-----Original Message-----
From: Lawrence Rhodes [mailto:[EMAIL PROTECTED]
Sent: Friday, May 04, 2007 9:22 AM
To: Electric Vehicle Discussion List;
[EMAIL PROTECTED]; ETList; SFEVA;
[EMAIL PROTECTED]; [EMAIL PROTECTED];
[EMAIL PROTECTED]
Subject: Jay Leno no friend of electric cars.
I can't believe Jay Leno (the ultimate car geek) compares a Baker
Electric to a Rav4 EV. They may have the same range but not the same
speed or
convienences. I'm sure he's taken a ride in a Tzero or Tesla. He at
times
acts like a spokesman for GM & then crows the 0 emmissions standard of
his steam car. He is so contrary sometimes I just don't understand his
agenda.
Lawrence Rhodes....
--- End Message ---
--- Begin Message ---
Hey Timothy,
The event is two days, Saturday and Sunday. We have the ScooterCross
on Saturday. Maybe your son can race a scooter at the ScooterCross. I
need to check with Mike Harvey about the ScooterCross rules but I
think it's open to youngsters.
And how about getting that Jr. Dragster going?
As far as racing on the drag strip. You need a driver's license
unless you are a Jr. Dragster driver.
Before you know it he'll be sixteen so you'll have plenty of time to
build something.
Chip Gribben
Power of DC June 2-3, 2007
http://www.powerofdc.com
On May 4, 2007, at 1:00 PM, Electric Vehicle Discussion List wrote:
From: [EMAIL PROTECTED]
Date: May 4, 2007 12:42:43 PM EDT
To: ev@listproc.sjsu.edu
Subject: Re: AGNS bike sets new NEDRA record
If you find something they will let him run bring your son down to
Ohio to our shop and let's get it built !!!!
Maybe my 12 year lod son Trevor can help out as well. I've got
lot's of goodies laying around.
Shawn
-----Original Message-----
From: [EMAIL PROTECTED]
To: ev@listproc.sjsu.edu
Sent: Fri, 4 May 2007 10:55 AM
Subject: Re: FW: AGNS bike sets new NEDRA record
In light of receiving recent information, I would like to redirect
the below
comments to Denis Stanislaw.
Also with the appropriate amount of accolade going to Shawn for his
dedication,
inspiration and encouragement.
It goes beyond your shop.....
3 days, wow.
I have a 14 yr old son drooling about building something from
scratch... and
PoDC is just weeks away...
Is there a minimum age limit at the track, for other than Jr.
Dragsters.
Can a 14yr old drive a bike, how about a Legends car? Will
Hagerstown let me run
a 50mph Elec-trak? ;-)
--
Stay Charged!
Hump
I-5, Blossvale NY
--- End Message ---
--- Begin Message ---
This is another thing that sends shivers up my spine, the thought of
lightening a flywheel. Be very, very sure the person who's doing it knows
what they are doing. There is a lot of centrifugal force acting on a
flywheel when they are spinning, and they have been known to fly apart if
they are structurally compromised, even just overheated a few too many
times. Don Garlits (the first guy into the 7's), I believe, lost a big
chunk of his foot to a flywheel explosion.
Back when I was racing, there were rules about that sort of thing. If you
wanted a light flywheel, you bought one that was approved. Even then, in
the faster classes, you ran a scattershield, pretty much a bullet proof bell
housing, or what amounts to a bullet proof vest for the trans. In stock
classes, you could run a stock flywheel, but I suspect they'd frown upon
having it lightened. In my camaros, I ran an aluminum race flywheel, and a
factory high performance lightweight steel flywheel. Neither was terribly
expensive. Depending on what you're driving, you may be able to buy one for
not much more than the cost of the machine work anyway. There used to be
places around that could make flywheels for anything to spec.
Marty
----- Original Message -----
From: "David Hankins" <[EMAIL PROTECTED]>
A flywheel can be made "light" for EV use as you don't need the outer Gear
ring for the starter and you don't need all that mass to keep the motor
running smoothly at idle or to keep you from stalling the motor at low
rpms.
So, you can machine off the outer diameter down to only the area needed
for
the clutch. The thickness can be reduced and any additional material not
required for structural integrity can be removed with further machining
and
drilling.
David
--- End Message ---
