EV Digest 6783
Topics covered in this issue include:
1) Re: Solectra/Azure Dynamics DMOC445 AC controller
by Mike Scott <[EMAIL PROTECTED]>
2) RE: Charging timer
by "Roger Stockton" <[EMAIL PROTECTED]>
3) Re: Here are the calculations. (was: Using Audio Capacitors
for Dragsters)
by Bill Dube <[EMAIL PROTECTED]>
4) Re: Shave My Adapter?
by Mike Scott <[EMAIL PROTECTED]>
5) O.T. Water-fueled engine appears on the horizon
by Dennis Foulke <[EMAIL PROTECTED]>
6) Re: "Honey, I Shrunk the Tires"
by Paul <[EMAIL PROTECTED]>
7) Re: Using Audio Capacitors for Dragsters
by Lee Hart <[EMAIL PROTECTED]>
8) RE: direct drive or transmission?
by "Dustin Stern" <[EMAIL PROTECTED]>
9) article: A123 announces PHEV auto-class battery system
by Paul Wujek <[EMAIL PROTECTED]>
10) Re: direct drive or transmission?
by Ian Hooper <[EMAIL PROTECTED]>
11) RE: "Honey, I Shrunk the Tires"
by "midiguy732" <[EMAIL PROTECTED]>
12) AGNS Rained Out
by [EMAIL PROTECTED]
13) Re: direct drive or transmission?
by "George Swartz" <[EMAIL PROTECTED]>
14) DON'T RESPOND : O.T. Water-fueled engine appears on the horizon
by "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
15) RE: direct drive or transmission?
by "Eidson, Mark" <[EMAIL PROTECTED]>
16) RE: "Honey, I Shrunk the Tires"
by "Phil Marino" <[EMAIL PROTECTED]>
17) Re: belly pan plastic
by DM3 <[EMAIL PROTECTED]>
18) Odyssey Batteries
by [EMAIL PROTECTED]
19) Re: Solectra/Azure Dynamics DMOC445 AC controller
by "Michaela Merz" <[EMAIL PROTECTED]>
20) Re: Dicover Batteries
by "Michaela Merz" <[EMAIL PROTECTED]>
21) Re: Fallbrook CVT
by "chad plantenberg" <[EMAIL PROTECTED]>
22) Re: EVLN(USE BASIC WOODWORKING SKILLS TO CONSTRUCT YOUR VERY OWN EV)
by "Bob Rice" <[EMAIL PROTECTED]>
23) Re: belly pan plastic (Coroplast notes & tips)
by "Adrian DeLeon" <[EMAIL PROTECTED]>
24) Re: belly pan plastic
by Victor Tikhonov <[EMAIL PROTECTED]>
25) Re: direct drive or transmission?
by "chad plantenberg" <[EMAIL PROTECTED]>
--- Begin Message ---
This is definately NOT the case now.
I asked about driving my tach, and within days had the proper parameter
file for my controller (it's changed since 2005 at least) and the logon
info for their ftp site, where I was able to download the documentation
and the exe to change the parameters. My advice: try again...
You will need a 232 cable, they want an awful lot for it, I just ordered
the pins from Mouser Electronics and made my own. The AMP part number is
in the docs, and my controller had the housing in the connector
(AMP-Seal) to keep water out.
Mike Scott in SJ, CA Got Juice?
Peter VanDerWal wrote:
I don't know about now, but back when they were Solectra I asked them
about changing the programming on one of their controllers and charger. I
owned the controller & charger, I was going to pay them to change the
programming (it was setup for a special LiIon project with canbus)
Email: no response
Called them up: told me to email them
Email: no response
Called them again: told me they didn't know why I didn't get a response,
but would forward it to their tech folks and I would get a response right
away. No response
Emailed again: no response
Called again: asked for my email address and promised a response within
the week. No response
I gave up.
--- End Message ---
--- Begin Message ---
Chris Tromley wrote:
> I think the simplest way to handle this is to have a basic total-time
> timer upstream of the charger and continue to use the
> start-on-acceptance timer mode in the PFC. You still get proper
> charging every time. You set the AC-in timer for something longer
> than your maximum charge time (determined experimentally). If a
> thermal runaway occurs it will be stopped before any significant
> damage can be done.
>
> I'm going to get the McMaster-Carr mechanical timer. It's the only
> one I've found that doesn't care what voltage goes through it and can
> handle the current draw. BTW, this timer has contacts rated at 28 A.
I see three possible approaches/solutions, each of which have pros and
cons:
-mechanical timer (e.g. McMaster Carr 7672K56 ($74, 28A, 0-12hr)). Pro
is that if AC is interrupted while the timer is running, it resumes
rather than resets when AC is restored. Disadvantage of either is that
the user must manually set/start the timer each time the vehicle is
plugged in or else the charger will either not start, or will turn off
prematurely.
-electro-mechanical timer (e.g. McMaster Carr 7037K15 ($57, 40A,
0-24hr). Pro is that if AC is interrupted while the timer is running,
it resumes rather than resets when AC is restored. Advantage of the
7037K15 24hr timer is that it can be set to delay the start of charge,
as well as to limit the max charge duration. Disadvantage is that the
user must manually set/start the timer each time the vehicle is plugged
in or else the charger will either not start, or will turn off
prematurely.
- delay relay (e.g. <http://www.electrodepot.com/a4758.htm> or
<http://www.electrodepot.com/a4160.htm> (12,24VDC, 120-240VAC, 10A,
$80), or <http://www.magnecraft.com/products/e104_sec4_pg06-07_821.pdf>
(24-240VAC/DC, 15A, 0.1-10hr, [EMAIL PROTECTED]), or McMaster Carr p/n 7801K51
(24-240VAC/DC, DIN rail mount 1-10hr/10-100hr delay relay, $30)). If
the native current capability (10-15A) is sufficient, one of the
universal 24-240VAC/DC input units is a self-contained solution. If
not, use the delay relay to control a heavier-duty relay (e.g. Digikey
PB299-ND, 40A, $10), and use a universal input 24VDC adapter (e.g.
<http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1616>,
$30) to power the delay relay and the coil of the heavy-duty relay. The
pro of this setup is that it is completely automatic; each time AC is
applied, the heavy duty relay is energised by the delay relay and after
the preset max charge time the heavy duty relay is turned off,
interrupting power to the charger. The con is that the delay relay will
restart, rather than resume, timing after an AC outage.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Actually, it isn't the high discharge rates per se that reduce the
cycle life. It is the elevated temperatures that occur during the
cycle life tests when you do the high-rate discharges.
The elevated temperatures really cut into the cycle life. We were
discussing that at the track with the A123 Systems engineers. We hold
the pack at 75 C all day when we are at the track, so this will
reduce the cycle life by a factor of about 10X. We will only get
about 1,000 50% DOD cycles. Considering that we discharge about 10%
DOD, this means we will only get somewhere between 2,000 and 5,000
full-power runs down the strip out of a battery pack. This is only 5
or 10 years for the typical weekend bracket race car. Then again, if
we were bracket racing, we would not bother to heat the pack. We
would just set our dial-in a bit higher.
By the way, there were several folks that had fundamental
misunderstandings about drag racing. Most people think that you need
lots of HP at the start, and very little at the end. This is
completely the opposite of what is really happening. When you are
running an ICE, it makes no difference if this is what you think
because it doesn't matter. When you are running electric, however, it
makes all the difference in the world.
If you mistakenly think that you need lots of HP in the beginning,
and very little later on, this would lead you to believe that
capacitors will be a good choice for a power source.
Bill Dube'
At 05:50 PM 5/16/2007, you wrote:
look, bill, all was fine until you made some crack about not knowing
about drag racing, that is insulting, you are better than that.
I see that indeed the A123 cells are more powerful per kg than the
400F Ness caps I provided a link to. But lets also acknowledge
that the A123 cells are a recent significant improvement in
batteries, and that caps will continue to advance as well.
So making a statement that caps aren't the best choice for drag
racing isn't something I would go on record with. If you take into
account that the lifetime of A123 cells at these 30C discharge rates
compared to currently available caps, then using even todays caps
might very well be the "best" choice if not the ultimate in
performance, and it may very well be the best choice to boost
performance in a road car, if they allow you to avoid the
life-killing high discharge rates used with the batteries to accelerate.
Jack Murray
Bill Dube wrote:
I went to the Ness website and browsed the ultra capacitors to see
where the current specs were these days.
Under very gentle discharge, ultra caps have a specific energy in
the range of 2 to 5 Watt-hours/kg. (This will be much lower under
high discharge. You won't get even half of that at max power.) Here
are a few comparisons:
AGM lead-acid ~ 30 W-hr/kg
NiCads ~ 45 W-hr/kg
Li-Ion FePo ~ 110 W-hr/kg
Now you are getting a glimpse at the problem. (This is why the
folks using caps pushed the car to the starting line, by the way.)
It takes at least 500 Watt-hours to get the KillaCycle to make a
fast run down the strip. This is about how much energy it takes to
get a 619 lb bike with a 135 lb driver to cover the 1/4 mile in the
8's. This does not include the burn out, the trip to the starting
line, or the trip back to the pits. This weight assumes your ultra
caps weigh just 161 lbs.
If you use the least-powerful ultra caps that have the most energy
per kg, and you (incorrectly) assume that you will be able to
extract the total maximum specific energy from them, the pack will
weigh a minimum
of 100 kg = 220 lbs. This is about 60 lbs heavier than the present
pack. Oops! The bike goes much slower because it weighs more AND is
has much less available HP. Let's fix the HP problem.
If you were to select capacitors that are more powerful, (on par
with A123 cells) the specific energy would drop to 2 (or less.)
This boosts the cap pack weight to 500/2 = 250 kg = 550 lbs! Oops!
The bike goes even slower, not faster.
As we discussed in a previous note, you can't get all the available
energy out of a pack of caps at the drag strip because the drag
racing discharge curve is "upside down" from what the caps are able
to deliver. You need about _twice_ the weight in caps to deliver
some sort of HP at least half-way down the track. This pushes the
pack weight up even more!
As the pack weight grows, this boosts the vehicle weight, which
boosts the HP and energy requirements in proportion. It is a losing
proposition. It just won't work.
Ultra caps are not the best choice for drag racing. This is obvious
if you just do a few simple calculations. You don't even need to do
the more detailed calculations because the numbers are so bad, even
making wildly optimistic assumptions.
Bill Dube'
"Nuff said"?
--- End Message ---
--- Begin Message ---
Not sure about the thickness, but the center mounting bolts are
completely different, unless you have a VW Type 4 taper hub. The main
difference between the 914 clutch and a (Type 1) VW clutch is the
diameter, the 914 has a 215mm clutch that only fits the 914 flywheel,
Type 1 VW's maxed out at 200mm. To use the 914 clutch you will need the
914 flywheel and the proper taper lock hub to fit it.
You probably already have a working clutch once you slide the taper lock
hub to put the flywheel closer to the throwout bearing. You want to end
up with a little free play at the clutch shaft in the forward direction
as possible. I'm assuming you have a hub that can slide of course...
Mike Scott in SJ, CA Got Juice?
Mark Hanson wrote:
Thanks Peter & Roland,
Thanks for your help. I'll look at Rolland's suggestions of what he did
which I appear to have the similar problem. A Porsche guy is selling me
a 914 clutch setup for $420 (and frame stiffener for $320 for the floppy
frame) so that should keep me busy next week welding again & changing
the clutch. He thought the Porsche clutch plate/disk & throuwout
bearing were thicker than the VW bug and that's why it's not
disengaging. The clutch cable was initially adjusted but the arm
bottoms out on the case. I tried washers behind the throw-out arm to
move it a bit closer but ran out of travel. The VW flywheel may have to
be changed to a Porsche flywheel if the Porsche is thicker but I dunno
and the engine was left in Knoxville (I'm in Roanoke, VA).
--- End Message ---
--- Begin Message ---
R. Colin Johnson <mailto:[EMAIL PROTECTED]> EE Times
<http://www.eetimes.com/;jsessionid=JHVI54LTY3K3SQSNDLPCKHSCJUNN2JVN>
(05/16/2007 1:49 PM EDT)
An EE professor at Purdue University has found a way to produce hydrogen
that replaces the need for gasoline by mixing water with beads of an
aluminum-gallium alloy. The discovery could lead to engines that
essentially burn water, instead of gasoline, since the gallium is not
consumed in the reaction and the aluminum can be recycled.
Purdue has patented the process and has issued an exclusive license for
it to an Indiana startup company, AlGalCo LLC.
EE professor Jerry Woodall discovered the process in the lab by
accident, while cleaning a crucible containing liquid alloys of gallium
and aluminum
"When I added water to this alloy, there was a violent poof," said
Woodall. "When the aluminum atoms in the liquid alloy came into contact
with the water, they reacted, splitting the water and producing hydrogen
and aluminum oxide."
Woodall claims that several industrial process problems need to be
solved before the water-fueled engine can become commercially viable.
But eventually, he said, it could be used both in engines that burn the
hydrogen directly and to charge up hydrogen fuel cells.
The reaction has no toxic by-products and can produce two kilowatts of
power from a pound of aluminum, said Woodall. For a 350-mile trip in an
automobile, it would take about 350 pounds of aluminum at a cost of
about $60, since the aluminum oxide left over after the reaction could
be converted back into aluminum-gallium pellets for reuse.
--- End Message ---
--- Begin Message ---
On May 16, 2007, at 7:55 AM, [EMAIL PROTECTED] wrote:
But I believe you are trading mileage for traction. A skinnier
hard tire will not be as good in the rain, a hard stop and hard
cornering.
You can also remove bumpers and seatbelts to save weight and also
improve mileage.
There is more to choosing an EV tire than that. Most of us in western
WA know that too wide a tire can be bad for rain traction. There is a
balance in tire selection. I do want to point out that excessively
small tires can be downright dangerous in an EV. You need to watch
the load ratings as well.
As far as your second point - I'm way ahead of you. Check out
<evalbum.com/125.html> I found steel bodywork to be excessive too.
Paul "neon" G.
--- End Message ---
--- Begin Message ---
Jeff Major wrote:
I have tested a lot of Optimas and never saw anything
close to 3 milliOhms. Always much higher. On the
other hand, when testing Maxwell ultracaps, the
resistance is lower than spec. Tested on a 9 pack of
2600 Farad cells (22.5 volts) was 4 milliOhms and did
not change much with temperature or state of charge.
The 9 cell pack weighed 14 pounds. Optima about 40
pounds. Hence a much better power density for the
cap.
The Optimas I've tested have ranged from 2.7 to 3.5 mohms, determined by
the change in voltage divided by the change in current when switching
between a 25a and 75a load. This is for new, fully charged batteries
after break-in, at about 75 deg.F.
The resistance drops if they are hotter. It rises as they get colder, or
as state of charge drop, and as they age. An advantage of capacitors is
that their internal resistance does not vary as much over these conditions.
--
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 ---
Thanks Peter. I should have added that since I have to use an intermediate
shaft if I go with direct drive that I will definitely be optimizing the
ratio.
Dustin
-----Original Message-----
From: Peter VanDerWal [mailto:[EMAIL PROTECTED]
Sent: Wednesday, May 16, 2007 7:20 PM
To: ev@listproc.sjsu.edu
Subject: Re: direct drive or transmission?
At 60 mph, the wheels on your vehicle will be turning at less than 1,000
RPM. That is way to slow for your proposed motor. You will need at least
a single speed transmission. A multispeed will improve your performance
and efficiency.
Direct drive requires motors specially built to operate at low RPM.
>
> Well, as long as I'm on a posting roll today...
>
> Can I solicit some comments about whether I should opt for direct drive or
> a transmission in my EV project?
>
> These are the known parameters so far:
> 1) Z1k controller (the 348v version) (purchased and awaiting assembly)
> 2) 15 to 20 Optimas, ideally 180v but I may opt for two strings of 120v.
> 3) Loaded weight is 2100-2200lbs including 20 optimas and driver, aprox.
> 4) Targeting 40+ range and powerful acceleration. Online EV computers
> estimate 220 watt hours per mile but I think that is much more than
> needed. I have not decided my final purpose, but it would be nice to be
> able to use it for my daily commute in addition to and EV events.
> 5) Vehicle is a streamlined 3 wheel vortex (see www.vortexplans.com). The
> Vortex has one wide wheel in back and two up front.
> 6) Initially planning on using a Netgain Warp 9. I have checked the
> performance charts available on Netgain's site and talked to a
> representative.
>
> One EVer recently suggested I use two smaller motors. I would like to be
> able to climb hills and still get up to 70mph on the highway, so it's been
> my thinking to use a small transmission, possibly either a Harley or an
> MR2 tranmssions (welded on one side).
>
> Any knowledgable comments about whether to use multiple motors (and what
> kind) or multiple gears would be appreciated.
>
> Thanks in advance,
> Dustin
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
--- End Message ---
--- Begin Message ---
I think that a few people on the list will find this interesting:
http://tyler.blogware.com/blog/_archives/2007/5/16/2953846.html
--
Paul Wujek ([EMAIL PROTECTED])
--- End Message ---
--- Begin Message ---
I'm in a similar boat - 2200lbs vehicle, 1000A speed controller, and
was also planning on a Warp9 if keeping the transmission, but am now
considering options for direct drive. Not having gears seems far more
elegant!
Correct me if I'm wrong (anyone), but it seems to me like generally
you need about 50% more power for direct drive conversions, and need
to run at the equivalent of 4th gear (final drive ratio of about
3.5:1), so you've got enough torque down low without running out of
revs up high. Most series DC motors peg out at a little over 5Krpm.
Right now I'm considering siamesing (a new verb for you) two ADC
6.7s, since it'd have comparable power to a WarP 11 and *hopefully*
still fit down the gearbox tunnel of the MX5. I think a 6.7"-block-of-
wood test is in order.
-Ian
On 17/05/2007, at 3:50 AM, Dustin Stern wrote:
Well, as long as I'm on a posting roll today...
Can I solicit some comments about whether I should opt for direct
drive or a transmission in my EV project?
These are the known parameters so far:
1) Z1k controller (the 348v version) (purchased and awaiting assembly)
2) 15 to 20 Optimas, ideally 180v but I may opt for two strings of
120v.
3) Loaded weight is 2100-2200lbs including 20 optimas and driver,
aprox.
4) Targeting 40+ range and powerful acceleration. Online EV
computers estimate 220 watt hours per mile but I think that is much
more than needed. I have not decided my final purpose, but it
would be nice to be able to use it for my daily commute in addition
to and EV events.
5) Vehicle is a streamlined 3 wheel vortex (see
www.vortexplans.com). The Vortex has one wide wheel in back and
two up front.
6) Initially planning on using a Netgain Warp 9. I have checked
the performance charts available on Netgain's site and talked to a
representative.
One EVer recently suggested I use two smaller motors. I would like
to be able to climb hills and still get up to 70mph on the highway,
so it's been my thinking to use a small transmission, possibly
either a Harley or an MR2 tranmssions (welded on one side).
Any knowledgable comments about whether to use multiple motors (and
what kind) or multiple gears would be appreciated.
Thanks in advance,
Dustin
--- End Message ---
--- Begin Message ---
> There is more to choosing an EV tire than that. Most of us in western
> WA know that too wide a tire can be bad for rain traction. There is a
> balance in tire selection. I do want to point out that excessively
> small tires can be downright dangerous in an EV. You need to watch
> the load ratings as well.
Wide tires are fine in the wet if they are specifically designed for
this purpose. Look at the various open wheel racing classes (Formula
One for example) - wide, wide tires with an incredible contact patch -
and with their rain tires they stick just fine - in incredibly
lightweight vehicles with tremendous horsepower.
As I said before, maybe not that well, tire selection really depends on
the purpose of the vehicle. A utilitarian vehicle would be tired one
way, and a corner carver another. And there's more to vehicle dynamics
than tires. Unsprung weight, suspension type front and rear, vehicle
weight, aerodynamics, weight distribution front/rear/left/right, FWD,
RWD or AWD, driver position, venting, impact resistance and so on.
If someone is converting an existing car to EV, then you have your
vehicle dynamics spelled out for you - what you bought is what you get
unless you want to re-engineer the car during your EV conversion.
And paul makes a good point about load ranges of tires - even if you're
not at the limit of the load rating of the tires, keep in mind the tires
are bouncing off surface irregularities and at certain times there is
very little load on the tire, and other times there could be easily 3x
the normal, static load on that tire.
And anyone who has enjoyed the tire blowout experience will tell you,
it's unpleasant at best - whether on a race car or a Ford Tempo.
--- End Message ---
--- Begin Message ---
A trip for naught is how to describe our Wednesday night. Weather in
Ohio was siffy so I called to confirm grudge night was on at Thompson
Raceway. Seems someone changed their mind on our way there because we
turned around at an empty track.
Saturday is a agonizing 3 days away. Time for more tuning...
Shawn
________________________________________________________________________
AOL now offers free email to everyone. Find out more about what's free
from AOL at AOL.com.
--- End Message ---
--- Begin Message ---
Ian, Depending on where you live, you may not be able to negotiate the
steepest grades if you have a direct drive. There are grades over 20% in
both Seattle and San Francisco. Even if you have enough torque, your motor
will heat up with the high current. In my opinion, it is better to have
gear selection - at least one gear change. Direct drives are either a
compromise drive train or a low performance vehicle like a golf cart or city
trolley bus. I have built EV's both ways and I didn't like my results with
direct drive. For direct drive to attain full performance, you will need a
very large motor and one heck of a large controller, etc.
On Thu, 17 May 2007 09:43:34 +0800, Ian Hooper wrote
> I'm in a similar boat - 2200lbs vehicle, 1000A speed controller, and
> was also planning on a Warp9 if keeping the transmission, but am
> now considering options for direct drive. Not having gears seems
> far more elegant!
>
> Correct me if I'm wrong (anyone), but it seems to me like generally
> you need about 50% more power for direct drive conversions, and need
> to run at the equivalent of 4th gear (final drive ratio of about
> 3.5:1), so you've got enough torque down low without running out of
> revs up high. Most series DC motors peg out at a little over 5Krpm.
>
> Right now I'm considering siamesing (a new verb for you) two ADC
> 6.7s, since it'd have comparable power to a WarP 11 and *hopefully*
> still fit down the gearbox tunnel of the MX5. I think a 6.7"-block-
> of- wood test is in order.
>
> -Ian
>
> On 17/05/2007, at 3:50 AM, Dustin Stern wrote:
>
> >
> > Well, as long as I'm on a posting roll today...
> >
> > Can I solicit some comments about whether I should opt for direct
> > drive or a transmission in my EV project?
> >
> > These are the known parameters so far:
> > 1) Z1k controller (the 348v version) (purchased and awaiting assembly)
> > 2) 15 to 20 Optimas, ideally 180v but I may opt for two strings of
> > 120v.
> > 3) Loaded weight is 2100-2200lbs including 20 optimas and driver,
> > aprox.
> > 4) Targeting 40+ range and powerful acceleration. Online EV
> > computers estimate 220 watt hours per mile but I think that is much
> > more than needed. I have not decided my final purpose, but it
> > would be nice to be able to use it for my daily commute in addition
> > to and EV events.
> > 5) Vehicle is a streamlined 3 wheel vortex (see
> > www.vortexplans.com). The Vortex has one wide wheel in back and
> > two up front.
> > 6) Initially planning on using a Netgain Warp 9. I have checked
> > the performance charts available on Netgain's site and talked to a
> > representative.
> >
> > One EVer recently suggested I use two smaller motors. I would like
> > to be able to climb hills and still get up to 70mph on the highway,
> > so it's been my thinking to use a small transmission, possibly
> > either a Harley or an MR2 tranmssions (welded on one side).
> >
> > Any knowledgable comments about whether to use multiple motors (and
> > what kind) or multiple gears would be appreciated.
> >
> > Thanks in advance,
> > Dustin
> >
> >
--- End Message ---
--- Begin Message ---
This subject is not appropriate for the EVDL. Please do not respond on list to
this off topic posting. Responses should be sent to the original poster's
private
email address.
Thanks.
David Roden
EVDL Administrator
--- End Message ---
--- Begin Message ---
Recent postings indicate that you need a minimum of twice the capacity
of your targeted range with AGM batteries to have a decent pack life so
you probably need more like 30 batteries or a 110 watt-hours per mile.
I guess the transmission will depend on how long steep your hills the
hills you need to climb and where they are in your commute. Direct
drive to me means that there is a fixed gear ratio between the motor and
wheel as apposed to a hub drive where the motor and wheel hub are at a
1:1 ratio. I would figure the drive ratio to have your top speed at
something less than the max motor RPM for a sagged battery pack voltage.
With a Warp9, AGM batteries and your sized and shape vehicle
acceleration will not be a problem with a Zilla 1K. Top speed will be
determined by the power required for your vehicle at speed and battery
pack voltage at that current draw. If you have steep hills a
transmission to increase the gear ratio may help by reducing the current
required to climb the hill which helps the battery capacity and motor
heating at a loss of efficiency and addition of weight and complexity
for the drive train. I opted for a direct drive of 4.75:1 using a
jackshaft with a primary belt and secondary chain for my 800 lbs of
motorcycle and passenger with 6 65ah AGMs driving an ADC L91-4003 thru a
Zilla 1K. I have a 15 mile round trip on level ground with a few starts
and stops and a 50 MPH top commute speed. I hope to have pretty good
acceleration and a top speed of 65MPH. I'm not sure if my 72 volt pack
will get me up to 65 with that ratio. I guess I will find out when the
Zilla 1K eventually get here some time this month.......me
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Dustin Stern
Sent: Wednesday, May 16, 2007 12:51 PM
To: ev@listproc.sjsu.edu
Subject: direct drive or transmission?
Well, as long as I'm on a posting roll today...
Can I solicit some comments about whether I should opt for direct drive
or a transmission in my EV project?
These are the known parameters so far:
1) Z1k controller (the 348v version) (purchased and awaiting assembly)
2) 15 to 20 Optimas, ideally 180v but I may opt for two strings of 120v.
3) Loaded weight is 2100-2200lbs including 20 optimas and driver, aprox.
4) Targeting 40+ range and powerful acceleration. Online EV computers
estimate 220 watt hours per mile but I think that is much more than
needed. I have not decided my final purpose, but it would be nice to be
able to use it for my daily commute in addition to and EV events.
5) Vehicle is a streamlined 3 wheel vortex (see www.vortexplans.com).
The Vortex has one wide wheel in back and two up front.
6) Initially planning on using a Netgain Warp 9. I have checked the
performance charts available on Netgain's site and talked to a
representative.
One EVer recently suggested I use two smaller motors. I would like to
be able to climb hills and still get up to 70mph on the highway, so it's
been my thinking to use a small transmission, possibly either a Harley
or an MR2 tranmssions (welded on one side).
Any knowledgable comments about whether to use multiple motors (and what
kind) or multiple gears would be appreciated.
Thanks in advance,
Dustin
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From: "midiguy732" <[EMAIL PROTECTED]>
Reply-To: ev@listproc.sjsu.edu
To: <ev@listproc.sjsu.edu>
Subject: RE: "Honey, I Shrunk the Tires"
Date: Wed, 16 May 2007 21:56:22 -0400
> There is more to choosing an EV tire than that. Most of us in western
> WA know that too wide a tire can be bad for rain traction. There is a
> balance in tire selection. I do want to point out that excessively
> small tires can be downright dangerous in an EV. You need to watch
> the load ratings as well.
Wide tires are fine in the wet if they are specifically designed for
this purpose. Look at the various open wheel racing classes (Formula
One for example) - wide, wide tires with an incredible contact patch -
and with their rain tires they stick just fine - in incredibly
lightweight vehicles with tremendous horsepower.
As I said before, maybe not that well, tire selection really depends on
the purpose of the vehicle. A utilitarian vehicle would be tired one
way, and a corner carver another. And there's more to vehicle dynamics
than tires. Unsprung weight, suspension type front and rear, vehicle
weight, aerodynamics, weight distribution front/rear/left/right, FWD,
RWD or AWD, driver position, venting, impact resistance and so on.
If someone is converting an existing car to EV, then you have your
vehicle dynamics spelled out for you - what you bought is what you get
unless you want to re-engineer the car during your EV conversion.
And paul makes a good point about load ranges of tires - even if you're
not at the limit of the load rating of the tires, keep in mind the tires
are bouncing off surface irregularities and at certain times there is
very little load on the tire, and other times there could be easily 3x
the normal, static load on that tire.
Yes - but the tire load rating ( on the sidewall) is the maximum normal
static load. Allowances have already been made for momentarily higher loads
due to bumps, cornering, braking, etc.
So, you don't have to worry about that. You can safely use a tire if the
static load on it (vehicle at rest) is equal to or less than the sidewall
rating at that pressure.
Phil Marino
And anyone who has enjoyed the tire blowout experience will tell you,
it's unpleasant at best - whether on a race car or a Ford Tempo.
_________________________________________________________________
More photos, more messages, more storageget 2GB with Windows Live Hotmail.
http://imagine-windowslive.com/hotmail/?locale=en-us&ocid=TXT_TAGHM_migration_HM_mini_2G_0507
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I use the 4x8 ft sheets of ABS plastic .090 inches thick. It costs about $25
for the sheet and is
easy to cut and drill. One advantage is you can use heat to bend and shape it
around corners or
fold up a box. It is pretty durable and if you dont plan on impacting it -
will last quite a
while. It comes in black and has one side with a wrinkle finish while the
apposite side is
glossy. Any plastic sheet distributor will carry it.
Mario
> > Date: Tue, 15 May 2007 23:15:27 -0500
> From: Danny Miller <[EMAIL PROTECTED]>
> To: ev@listproc.sjsu.edu
> Subject: Re: belly pan plastic
>
> Lexan (a trade name for polycarbonate) is a poor choice for impact
> resistance. It is actually somewhat brittle, relatively speaking.
> Unless you need the clarity, there is no reason to use it. Also, Lexan
> scratches easier than acrylic (Plexiglass) and will be probably rapidly
> scratched by road debris being under the vehicle.
>
> They go:
> LDPE
> HDPE
> UHMW-PE
>
> UHMW-PE is expensive but unbelievably tough. It is also chemically
> resistant to most anything it may come in contact with. However, all
> the PEs are subject to UV damage unless otherwise specified. There are
> some additives which may slow down the rate of UV damage. Black is
> always better but this is an unusual color to get. Polypropylene is
> more UV resistant than PE, but hardly "UV proof".
>
> However, being UNDER a car should not get that much UV. I suspect this
> will probably be safe even without a UV stabilized version.
>
> The corrugated plastic material is called "Coroplast", at least that's
> the biggest mfg'er. Coroplast is corrugated polypropylene and you'll
> find many signs are made from it, even some of those stuck into the
> ground by the road. It is readily available from any plastics supply
> store. It is cheap, light, and tough, though nowhere near as strong as
> a 1/8" sheet of UHMW. However, I'd suspect it's strong enough to do
> this job! Given the low weight and cost, I expect this may be the best
> choice. Special mounting procedures would need to be used, generally
> this means large washers to spread out the force so it does not tear
> around the bolt holes.
>
> Danny
>
> David Roden wrote:
>
> >Solectria used a corrugated plastic material. It reminds me of the stuff
> >that US Postal Service carrying boxes are made from. (If you have a
> >business with a PO box, you probably have a collection of these boxes, so
> >you know what I mean.)
> >
> >David Roden - Akron, Ohio, USA
> >EV List Administrator
> >
>
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Peter wrote:
> As I said, I was dealing with Solectra. Perhaps Azure has replaced these
> folks or done something to encourage them to respond to requests. I don't
> know.
Not really. I was trying to get information from them in regard to the
availability of a/c motor/compressor combinations. That was 1/2 year ago.
Same experience you had. Called them -send email. Send email - no
response. Called again and asked for a specific content - mailed that
contact - no response.
So - I made my mind about Solectria/Azure. I think I wouldn't want to have
to deal with them, or, worse, be dependent on their information.
mm./
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To replace my T-125 floodies, I would have to use the Discover EVGH6A-A
which has approx. the same dimensions, same capacity (T-125's 5hr rate is
195AH, same as Discovers 5hr rate), though the Discover weight is about
two pounds more. Not bad as a drop-in replacement for floodies to save on
watering. However, one would have to re-program the charger, get some
electronics to balance the pack. But it looks like an alternative for
those of us who can carry the weight and don't like battery maintenance.
Any idea how much those batteries are?
Discover batteries at http://discover-energy.com/
mm./
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dont know anything specifically about it, but watched their demo
video. i would be nervous however that it would suffer from the same
inefficienies as your standard auto trans. the demo claims that your
torque is passed on through a fluid - same as auto trans. again, not
knowing details - makes me nervous that it would be likewise
inefficient.
chad
On 5/16/07, Bill Dennis <[EMAIL PROTECTED]> wrote:
Anyone know anything about the CVT made by this company:
http://www.fallbrooktech.com
Bill Dennis
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----- Original Message -----
From: "mike golub" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Wednesday, May 16, 2007 2:12 PM
Subject: Re: EVLN(USE BASIC WOODWORKING SKILLS TO CONSTRUCT YOUR VERY OWN
EV)
A Lumberghini?! Sorry, couldn't resist!
Seeya
Bob.......... If electricity comes from electrons,does morality come
from morons?
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On Wed, 16 May 2007 09:12:51 -0700, Lee Hart <[EMAIL PROTECTED]>
wrote:
If the goal is aerodynamics, then you may want something that bends and
curves easier than Coroplast. It is basically a flat rigid sheet, that
kinks if you bend it too much.
Coroplast bends quite a bit before it kinks. I use it to make model
airplane wings. A heat gun can be used to make tighter bends with no
kinks. Bends perpendicular to the corrugations will make smaller radiuses
before kinking.
The corrugations can be stuffed with bamboo skewers to prevent crushing
where screws/bolts will be used. Zip ties, staples, and machine screws all
work well for securing Coroplast. It WILL melt and MAY burn, so be
careful. There was an EVDL thread about a Coroplast belly pan that caught
fire! Coro will sag a bit when it warms up (car interior in summer) so
support it well.
A little known fact: Free Coroplast actually GROWS along busy roads and
intersections. These coro "crops" ripen just after elections :)
Coroplast belly pan on a Honda del Sol (lots of HOWTO pictures)
http://www.gassavers.org/showthread.php?t=671
Coroplast interior and grille block - sound deadening & weight reduction
http://www.gassavers.org/showthread.php?t=701
Coroplast R/C airplanes (good links to working with Coro - bending,
gluing, stiffening, etc.) The "hinge tool" is especially useful for
removing strips along a corrugation for easier bending and making hinges.
http://www.spadtothebone.com
EV Digest 5379 - Coro belly pan on EV catches fire when controller dies,
tips on working with Coroplast
http://www.mail-archive.com/ev@listproc.sjsu.edu/msg06448.html
-Adrian
.
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Unless it's liquid cooled...
Victor
Chip Gribben wrote:
Hey Al,
Whatever belly pan you use if it extends under the motor make sure your
motor gets plenty of air or is properly ventilated or your belly pan
will end up being a coffin for an overheated motor.
Chip
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in discussing 2 motors vs 1 - does anyone know how to calculate
voltage required in a 2 motor application? can you get away with less
voltage, since each motor is theoritcally only driving a portion of
the vehicle?
i saw Ian's comment that he believed you already need to add 50% for
direct drive. but then do you (roughly) halve that amount across 2
motors?
thanks
chad
On 5/16/07, Eidson, Mark <[EMAIL PROTECTED]> wrote:
Recent postings indicate that you need a minimum of twice the capacity
of your targeted range with AGM batteries to have a decent pack life so
you probably need more like 30 batteries or a 110 watt-hours per mile.
I guess the transmission will depend on how long steep your hills the
hills you need to climb and where they are in your commute. Direct
drive to me means that there is a fixed gear ratio between the motor and
wheel as apposed to a hub drive where the motor and wheel hub are at a
1:1 ratio. I would figure the drive ratio to have your top speed at
something less than the max motor RPM for a sagged battery pack voltage.
With a Warp9, AGM batteries and your sized and shape vehicle
acceleration will not be a problem with a Zilla 1K. Top speed will be
determined by the power required for your vehicle at speed and battery
pack voltage at that current draw. If you have steep hills a
transmission to increase the gear ratio may help by reducing the current
required to climb the hill which helps the battery capacity and motor
heating at a loss of efficiency and addition of weight and complexity
for the drive train. I opted for a direct drive of 4.75:1 using a
jackshaft with a primary belt and secondary chain for my 800 lbs of
motorcycle and passenger with 6 65ah AGMs driving an ADC L91-4003 thru a
Zilla 1K. I have a 15 mile round trip on level ground with a few starts
and stops and a 50 MPH top commute speed. I hope to have pretty good
acceleration and a top speed of 65MPH. I'm not sure if my 72 volt pack
will get me up to 65 with that ratio. I guess I will find out when the
Zilla 1K eventually get here some time this month.......me
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Dustin Stern
Sent: Wednesday, May 16, 2007 12:51 PM
To: ev@listproc.sjsu.edu
Subject: direct drive or transmission?
Well, as long as I'm on a posting roll today...
Can I solicit some comments about whether I should opt for direct drive
or a transmission in my EV project?
These are the known parameters so far:
1) Z1k controller (the 348v version) (purchased and awaiting assembly)
2) 15 to 20 Optimas, ideally 180v but I may opt for two strings of 120v.
3) Loaded weight is 2100-2200lbs including 20 optimas and driver, aprox.
4) Targeting 40+ range and powerful acceleration. Online EV computers
estimate 220 watt hours per mile but I think that is much more than
needed. I have not decided my final purpose, but it would be nice to be
able to use it for my daily commute in addition to and EV events.
5) Vehicle is a streamlined 3 wheel vortex (see www.vortexplans.com).
The Vortex has one wide wheel in back and two up front.
6) Initially planning on using a Netgain Warp 9. I have checked the
performance charts available on Netgain's site and talked to a
representative.
One EVer recently suggested I use two smaller motors. I would like to
be able to climb hills and still get up to 70mph on the highway, so it's
been my thinking to use a small transmission, possibly either a Harley
or an MR2 tranmssions (welded on one side).
Any knowledgable comments about whether to use multiple motors (and what
kind) or multiple gears would be appreciated.
Thanks in advance,
Dustin
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