EV Digest 5007
Topics covered in this issue include:
1) RE: VW body reinforcement
by "Paschke, Stephen" <[EMAIL PROTECTED]>
2) Re: Link 10 question
by "Roland Wiench" <[EMAIL PROTECTED]>
3) Re: VW body reinforcement
by [EMAIL PROTECTED]
4) RE: fast charging over 100 amps
by Tim Humphrey <[EMAIL PROTECTED]>
5) Maxing out a Zilla (crazy idea) was,
Re: Predictions for the Monster Garage '62 Electric Chevy?
by "Chris Robison" <[EMAIL PROTECTED]>
6) Re: Predictions for the Monster Garage '62 Electric Chevy?
by "BadFishRacing" <[EMAIL PROTECTED]>
7) Re: Failure Modes (was Re: Motor control for direct drive setup)
by Lee Hart <[EMAIL PROTECTED]>
8) Re: Clutchless shift with rpm-matching?
by Lee Hart <[EMAIL PROTECTED]>
9) Re: Clutchless shift with rpm-matching?
by Lee Hart <[EMAIL PROTECTED]>
10) Re: float charging GC batteries?
by Lee Hart <[EMAIL PROTECTED]>
11) Re: Predictions for the Monster Garage '62 Electric Chevy?
by "Rich Rudman" <[EMAIL PROTECTED]>
12) Re: VW body reinforcement
by "Paul Compton" <[EMAIL PROTECTED]>
13) Re: VW body reinforcement
by Electro Automotive <[EMAIL PROTECTED]>
14) Yahoo archive
by "Paul Compton" <[EMAIL PROTECTED]>
--- Begin Message ---
I plan on doing that on my 87 cabriolet conversion, At least on the top
of the struts. A lot of Nissan Z owners do that also.
I haven't heard of putting one on the bottom of the front struts, but
I'm not a tuner.
> Stephen Paschke
> Senior Consultant
> Keane, Inc.
> Office 303-607-2993
> Cell 303-204-9280
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Ken Albright
Sent: Monday, December 19, 2005 7:34 AM
To: Electric Vehicle Discussion List
Subject: VW body reinforcement
My 86 Scirocco conversion is finally under way. Talking to the local VW
guys, they are recommending crossbars to reinforce the body at the top
and bottom of the front struts and the top of the rear shocks. The
upper ones will get in the way of battery placement.
Anyone do this to your unibody conversion? More important, anyone wish
they had?
Thanks
Ken
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
**************************************************************
This message, including any attachments, contains confidential information
intended for a specific individual and purpose, and is protected by law. If
you are not the intended recipient, please contact sender immediately by reply
e-mail and destroy all copies. You are hereby notified that any disclosure,
copying, or distribution of this message, or the taking of any action based on
it, is strictly prohibited.
TIAA-CREF
**************************************************************
--- End Message ---
--- Begin Message ---
Hello Tim,
Check all the defaults in all the settings. This could throw it off some.
Also here something else:
I have two large GE amp and volt meters that are next to the Emeter. The GE
meters are custom made for my 180 volt battery that have a sweeping bar graph.
The voltage display goes from 150 to 230 volts.
If I charge the 180 volt pack up to 230 volts and run the EV for a mile run,
I'm reading about 210 volts on both meters. The AH is 2AH on the Emeter.
Now is I charge to 230 volts and let it set for 16 hours which the voltage will
float down to 190 volts, the AH reading is now 2.2 AH running the EV at the
same speed, same temperature and course. It always read more at the lower
voltage than the higher voltage.
If the voltage spread between 150 volt to 210 volts is 60 volts and the spread
between 150 and 190 is 40 volts, Therefore the lower voltage may increase the
amperes to yield the same watts per mile.
Roland
----- Original Message -----
From: TiM M<mailto:[EMAIL PROTECTED]>
To: [email protected]<mailto:[email protected]>
Sent: Sunday, December 18, 2005 8:17 PM
Subject: Link 10 question
It seems my E-meter has decided each % is equal to
1.3AH, every 10% I use it shows I'm down 13AH. My
batteries, US 145 are 244AH and that's what I set the
e-meter to. Shouldn't that work out to 2.4AH per
percent?
TiM
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com<http://mail.yahoo.com/>
--- End Message ---
--- Begin Message ---
The strut braces or cross bars that you refer to are more of a handling and
performance item. I have them for my Geo Metro (also a unibody), but got them
mainly for competition (autocross) purposes. In normal road use with 700 pounds
of batteries the Metro is already reasonably stable without them. Mine do not
intefere with battery placement so it was an easier decision for me.
Lawson
--- End Message ---
--- Begin Message ---
Good Job Steve;
Could your gas powered machine travel through that thick grass at that speed??
Stay Charged!
Hump
Original Message -----------------------
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of STEVE CLUNN
Sent: Saturday, December 17, 2005 10:14 AM
To: [email protected]
Subject: fast charging over 100 amps
Its been over a month since I started using my electric lawn mower on the
job , I have probable cut over 100 yard with it . I added 15 more 6v GC's
to my work truck ( 2 parallel strings of 120 v) with the idea of making a
dump charger for the 96v orbital pack on the mower. I really needed the
extra batteries with the mower taking 15ah per yard. I come home form time
to time having used 200 ah through the day . With some parts from an old
golf cart speed controller, the type a wiper and a coil for resistance will
lots of taps. Yesterday I got to try it out . The set up is just some heavy
cables form the truck pack to the mower with this golf cart
speed controller in-between. I had these 3 good size yards
together ( 3ed time cutting them with the e mower) . I cut 1 and 1/2 ( used
20 ah ) and go back to the truck to try out the dump charger. Plug it in and
start pushing the wiper along the pads . 40 60 80 and one pad away for full
its charging at 107 amp. 8-o not a sound just +107 ( Full on I saw 170
amps !) . My lawn customer
comes out and we are talking about the mower and hy bread cars , he's
telling me how they don't really pay and I'm making points about it being a
step in the right direction. I'm watching the e meter . and it's down to -5
ah in no time , still pumping around 100 amps and the voltage is about 13.6
. I've ready to go again and I said to my customer , look it's all charged
up . He was impressed , I was impressed . This puts an end to me ever
having to use a gas mower again. I haven't started my gas (back up) mower
since getting the electric going . When charging fast like this how hi can
the voltage go on a excide 12 v orbital , ?
Steve Clunn
You can see a video of it cutting some thick grass on www.grassrootsev.com
under projects .
--- End Message ---
--- Begin Message ---
This thread got me thinking ... There seems to be a great divide between a
Zilla's theoretical maximum power handling capability and what folks
normally get out of them on the strip, given the sag inherent in any
battery chemistry.
While one could reduce voltage sag by adding packs in parallel, the return
is diminishing and to eliminate sag completely you'd need a pack of
infinite mass.
So, I had a nutty idea I thought I'd kick around -- maybe someone better
at math than I am can give a rational explanation why this wouldn't
work...
First, choose a small, high-power battery like John's Aerobatteries, with
the intent on building a long series string. Find out how much they sag at
maximum current (2000A) and then size the pack such that at full bore at
the end of the strip you've sagged to the Zilla's voltage limit of around
350V. I don't know what the resulting pack voltage would be for any given
battery design, but I'm guessing it might be somewhere between 500 and
600V, maybe a little more. (Yes, here's where it gets a little weird, stay
with me....)
Now to prevent the Zilla from ever seeing an input voltage above its
maximum, say you had a simple voltage divider, made from two extremely
high-power oil-cooled rheostats with a tap to the controller between them.
A microcontroller actuating circuit would ensure the two rheostats were at
their optimum values for any particular power draw and input voltage from
the pack.
At rest or under very little current draw, the two rheostats would both be
at a high value, allowing the controller to see 350V but dissipating a
minimum amount of power. At full power (2000A) the lower rheostat would be
at "maximum" (an open switch, infinite resistance) and the upper one would
be at "minimum" (bypassed, zero resistance). Anywhere between rest and
full power, the two values would be adjusted to keep the Zilla at max
voltage while wasting as little power as possible.
The oil cooling the rheostats would be circulated through large separate
radiators to dissipate heat. An incredibly inefficient solution, but isn't
that part of what drag racing is about?
Two potential problems I can think of:
- Actuating the rheostats quickly enough
- I have no idea how big these would have to be to handle the power
dissipation implied by this idea
--chris
On Mon, December 19, 2005 12:34 am, David Dymaxion said:
> Assuming the batteries can max out the controllers:
>
> <http://www.cafeelectric.com> says a zilla can do 640 kW. 2 Zillas
> would give 1.28 MW (as in MegaWatts!).
>
> Converting 1.28 MW to hp gives 1700 hp. With around 20% motor and 15%
> driveline loss, that is still about 1200 rwhp.
>
> Can the batteries do it? 1.28 MW for batteries with 1.5 kW/kg would
> give about 1800 lbs of batteries, with 2800 lbs for the
> glider+motors+controllers. That's within the realm of possibility.
>
> So I don't know what exactly was done, if the batteries were maxed
> out, etc, but theoretically it is fun to dream!
>
> I'd propose we do a fun guess pool like before. Berube says 8's,
> Wayland says 13's. I'll do some of my own calculations and tender a
> guess, too. May the best bench racer win! :)
>
> --- John Wayland <[EMAIL PROTECTED]> wrote:
>> Hello to All,
>>
>> [EMAIL PROTECTED] wrote:
>>
>> >With 2 zillas and the
>> >power to feed them from the lithium pack the 4700lb chevy with all
>> the good
>> >suspension work should run 8.64 seconds in the qt.mi. at 157mph.I
>> would not
>> >expect this in your 1st run out but after 5-8 passes. These #s
>> come from the VERY
>> >predicitable Speedworld horsepower calc. on their site, but do not
>> include my
>> >multipiler. With that multiplier in the equa.you will run 8.48 in
>> the qt.mi.
>> >What a difference a little NITRO makes!!!! Dennis Berube
>> >
>> >
>>
>> Whoa, Dennis' ET predictions for the Monster Garage project Chevy
>> sure
>> seem 'optimistic'! I respect Dennis, he's a great competitor, a
>> friend,
>> and quite a character, too! He's still the top dog as far as having
>> the
>> quickest electric ET, too. However, as excited I am about the rad
>> one
>> week conversion that friends Rudman and Lawless did, these guys,
>> the
>> ones that helped build the thing, both feel low to mid 13's are
>> more
>> realistic, certainly not 12's....it's too heavy and there's just
>> not
>> enough raw power to get the job done.
>>
>> To investigate Dennis' predictions, I've done some research of my
>> own,
>> and offer the findings as balance to what I feel is a wild
>> prediction of
>> performance I personally, don't think is even close to being
>> correct...no offense is intended. I have tried very hard to keep
>> past
>> predictions of performance as accurate as possible, whether it's my
>> own
>> car, or someone else's. As an example, when Matt Graham first
>> contacted
>> me more than a year ago about his proposed twin motor electric
>> Nissan
>> 240SX, I predicted it would run easy 14's, and that it could get
>> into
>> the 13s'....he ran a 14.2 first time out. I've been pretty much
>> right on
>> the mark with my car all along, too.
>>
>> OK, here we go.....I plugged in a known performance spec list from
>> my
>> own White Zombie, at three different 1/4 calculator sites. The
>> first
>> one, Simple Horsepower Calculator, is at:
>>
>> http://www.dsm.org/tools/calchp.htm
>>
>> This site has open boxes where you can enter data:
>>
>> (1) Vehicle Weight (including driver weight)
>> (2) 1/4 Mile ET
>> (3) 1/4 Mile Trap Speed
>>
>> I entered my accurate data of 12.151 for the ET and 106.25 for the
>> mph,
>> and my estimated data of 2550 lbs. for vehicle (2350 lbs. & 200 lb.
>>
>> driver) weight. Historically, I've been within 50 lbs. on my
>> electric
>> conversion weights. The calculator came up with this:
>>
>> (1) Based on the ET, 281 hp
>> (2) Based on the mph, 239 hp
>>
>> Since drag racing EVs typically have a lower top end speed as does
>> a
>> gasser running the same ET, I tend to lean toward the mph based hp
>> levels.
>>
>> The second site, Horsepower Calculator, is at:
>>
>> http://www.s-series.org/htm/calc/hpcalc.htm
>>
>> This site has open boxes where you can enter data:
>>
>> (1) Known 1/4 mile ET
>> (2) Vehicle Weight (including driver weight)
>> (3) 1/4 Mile MPH
>> (4) 60 ft. Time
>>
>> Note that this site adds a box for the 60 ft. time, which I feel
>> really
>> improves the accuracy.
>>
>> I entered the same accurate data of 12.151 for the ET, 106.25 for
>> the
>> mph, and added 1.59 for a 60 ft. time, plus the estimated data of
>> 2550
>> lbs. for vehicle (2350 lbs. & 200 lb. driver) weight. The
>> calculator
>> came up with this:
>>
>> (1) RWHP (rear wheel horsepower) from entered ET of 280.93 hp
>> (2) RWHP from MPH of 238.71 hp
>> (4) Break hp from ET of 337.116 hp
>> (5) Break hp from MPH of 286.452 hp
>>
>> The third calculator site, National Driveline, is at:
>>
>> http://www.nationaldrivetrain.com/calcs/dragcalc.html
>>
>> This site has open boxes where you can enter data:
>>
>> (1) Vehicle Weight (including driver weight)
>> (2) Vehicle hp
>> (3) RPM through the finish line
>> (4) Tire diameter
>>
>> I used the same 2550 lbs. vehicle weight, and since the 239 hp from
>> the
>> first site and the 238.71 hp that the second site were pretty much
>> identical, I rounded it to 240 hp, 6900 rpm from our tach data and
>> calculations using the rear end ratio and tire diameter, and 24
>> inches
>> as the current diameter of the Goodyear Drag Radials (before we
>> burned
>> them down, these were actually 24.3 inch tires). The third
>> performance
>> calculator came up with this:
>>
>> (1) 1/4 Mile ET of 12.23
>> (2) 1/4 Mile Top End Speed of 106.52 mph
>> (3) Ideal Gear Ratio of 4.63
>> (4) 1/8 Mile ET of 7.79 seconds
>>
>> This data is surprisingly accurate. Compare the results to what the
>> car
>> actually did:
>>
>> Predicted ET of 12.23....actual ET of 12.151
>> Predicted top end speed of 106.52 mph....actual top end speed of
>> 106.25 mph
>> Suggested ideal gear ratio of 4.63....actual gear ratio is 4:57
>> Predicted 1/8 mile ET of 7.79 seconds....actual ET of 7.602 mph
>>
>> OK, now that I've demonstrated how accurate the three sites are
>> with a
>> known vehicle's performance, let's now use the first site, Simple
>> Horsepower Calculator, the one that seems to have nailed my car's
>> hp
>> pretty darn well, and see how Dennis' predictions of 8.48 seconds
>> and
>> 157 mph come out:
>>
>> Again, this site has open boxes where you can enter data:
>>
>> (1) Vehicle Weight (including driver weight)
>> (2) 1/4 Mile ET
>> (3) 1/4 Mile Trap Speed
>>
>> I entered the Chevy's 4900 lb. estimated weight (4700 lbs. + 200
>> lb.
>> driver) and Dennis' 8.48 ET and the 157 mpg figures. The calculator
>> came
>> up with these outrageous results:
>>
>> (1) Based on the ET, 1588 hp!!
>> (2) Based on the mph, 1480 hp!!
>>
>> I'm told the Chevy's incredible battery pack can deliver 3800 amps
>> at
>> around 170 volts, or a whopping 646 kw!
>> Now, though that's a huge amount of delivered power, in the real
>> world
>> of DC motors at BIG amps, a best case scenario is figuring 75%
>> efficiency, so for every hp generated (746 watts) the motors will
>> actually suck 1000 watts....this comes in at 646 hp, tops.
>>
>> OK Dennis, where do you come up with at the least, 1480 hp? Where
>> do you
>> get 157 mph? Where on earth, do you get 8.48 seconds?
>>
>> At the National Drivetrain site, I entered the Chevy's 4900 lb.
>> estimated weight (4700 lbs. + 200 lb. driver) and the more
>> realistic 646
>> hp figure, plus 5000 rpm and 26 inch tires. The calculator came up
>> with
>> these results:
>>
>> (1) 1/4 Mile ET of 10.98
>> (2) 1/4 Mile Top End Speed of 119.18 mph
>> (3) Ideal Gear Ratio of 3.25
>> (4) 1/8 Mile ET of 7 seconds
>>
>> Note, that if I'm off on the rpm or the tire size, it still doesn't
>>
>>
> === message truncated ===
>
>
>
>
> __________________________________________________
> Do You Yahoo!?
> Tired of spam? Yahoo! Mail has the best spam protection around
> http://mail.yahoo.com
>
>
--- End Message ---
--- Begin Message ---
I've tried to calculate the ability of ONE pack, but I guess I'll ask.
If each pack is good for 1200 watts, is that 100amps @12V (sagged down from
28V)?
BadFishRacing
----- Original Message -----
From: <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Monday, December 19, 2005 6:44 AM
Subject: Re: Predictions for the Monster Garage '62 Electric Chevy?
> John,
>
> As I said previously, the packs (as they are configured) are only good
> for a peak of 1.2kw each x 384 pcs.= 612 Hp.
> To put it another way 3200 amps at 144 volts total. I believe the
> cells are capable of more but the configuration we used was never
> intended to be punished the way we are treating them. When you see the
> show you, and others, will immediately see the weak link in the battery
> system. I base my performance numbers on the above figures because I
> know them to be attainable, (at least for short bursts).
>
> Assuming I can get the cells for my personal use let's try to get to
> Dennis' numbers.
> Here's what we know.
>
> 384 pc battery pack = 612 peak hp and 1000lbs, (including very heavy
> interconnects)
> We strip the cells from their heavy casings and replace connections
> with more efficient design
> Revised battery pack = 612 peak hp and 400 lbs
> OJ 2 chassis with 12 Lemco's and no battery or driver = 750lbs
> Non beer drinking Driver= 100 lbs
> Total GVW = 1250 lbs.
> Peak Wheel HP = 460 hp
>
> Now we're getting somewhere.
>
> My calculator shows 8 flat is feasible. If I can keep the brush gear
> from melting, the front end on the ground at least once in a while,
> etc, etc.....
>
> I think it would take the reactor from the Ronald Reagan Aircraft
> Carrier to get this 62 Chevy as it is into the 8's.
>
> Shawn
>
>
> -----Original Message-----
> From: John Wayland <[EMAIL PROTECTED]>
> To: [email protected]
> Sent: Sun, 18 Dec 2005 21:41:31 -0800
> Subject: Predictions for the Monster Garage '62 Electric Chevy?
>
> Hello to All,
>
> [EMAIL PROTECTED] wrote:
>
> >With 2 zillas and the >power to feed them from the lithium pack the
> 4700lb chevy with all the good >suspension work should run 8.64 seconds
> in the qt.mi. at 157mph.I would not >expect this in your 1st run out
> but after 5-8 passes. These #s come from the VERY >predicitable
> Speedworld horsepower calc. on their site, but do not include my
> >multipiler. With that multiplier in the equa.you will run 8.48 in the
> qt.mi. >What a difference a little NITRO makes!!!! Dennis Berube
> > >
>
> Whoa, Dennis' ET predictions for the Monster Garage project Chevy sure
> seem 'optimistic'! I respect Dennis, he's a great competitor, a friend,
> and quite a character, too! He's still the top dog as far as having the
> quickest electric ET, too. However, as excited I am about the rad one
> week conversion that friends Rudman and Lawless did, these guys, the
> ones that helped build the thing, both feel low to mid 13's are more
> realistic, certainly not 12's....it's too heavy and there's just not
> enough raw power to get the job done.
>
> To investigate Dennis' predictions, I've done some research of my own,
> and offer the findings as balance to what I feel is a wild prediction
> of performance I personally, don't think is even close to being
> correct...no offense is intended. I have tried very hard to keep past
> predictions of performance as accurate as possible, whether it's my own
> car, or someone else's. As an example, when Matt Graham first contacted
> me more than a year ago about his proposed twin motor electric Nissan
> 240SX, I predicted it would run easy 14's, and that it could get into
> the 13s'....he ran a 14.2 first time out. I've been pretty much right
> on the mark with my car all along, too.
>
> OK, here we go.....I plugged in a known performance spec list from my
> own White Zombie, at three different 1/4 calculator sites. The first
> one, Simple Horsepower Calculator, is at:
>
> http://www.dsm.org/tools/calchp.htm
>
> This site has open boxes where you can enter data:
>
> (1) Vehicle Weight (including driver weight)
> (2) 1/4 Mile ET
> (3) 1/4 Mile Trap Speed
>
> I entered my accurate data of 12.151 for the ET and 106.25 for the mph,
> and my estimated data of 2550 lbs. for vehicle (2350 lbs. & 200 lb.
> driver) weight. Historically, I've been within 50 lbs. on my electric
> conversion weights. The calculator came up with this:
>
> (1) Based on the ET, 281 hp
> (2) Based on the mph, 239 hp
>
> Since drag racing EVs typically have a lower top end speed as does a
> gasser running the same ET, I tend to lean toward the mph based hp
> levels.
>
> The second site, Horsepower Calculator, is at:
>
> http://www.s-series.org/htm/calc/hpcalc.htm
>
> This site has open boxes where you can enter data:
>
> (1) Known 1/4 mile ET
> (2) Vehicle Weight (including driver weight)
> (3) 1/4 Mile MPH
> (4) 60 ft. Time
>
> Note that this site adds a box for the 60 ft. time, which I feel really
> improves the accuracy.
>
> I entered the same accurate data of 12.151 for the ET, 106.25 for the
> mph, and added 1.59 for a 60 ft. time, plus the estimated data of 2550
> lbs. for vehicle (2350 lbs. & 200 lb. driver) weight. The calculator
> came up with this:
>
> (1) RWHP (rear wheel horsepower) from entered ET of 280.93 hp
> (2) RWHP from MPH of 238.71 hp
> (4) Break hp from ET of 337.116 hp
> (5) Break hp from MPH of 286.452 hp
>
> The third calculator site, National Driveline, is at:
>
> http://www.nationaldrivetrain.com/calcs/dragcalc.html
>
> This site has open boxes where you can enter data:
>
> (1) Vehicle Weight (including driver weight)
> (2) Vehicle hp
> (3) RPM through the finish line
> (4) Tire diameter
>
> I used the same 2550 lbs. vehicle weight, and since the 239 hp from the
> first site and the 238.71 hp that the second site were pretty much
> identical, I rounded it to 240 hp, 6900 rpm from our tach data and
> calculations using the rear end ratio and tire diameter, and 24 inches
> as the current diameter of the Goodyear Drag Radials (before we burned
> them down, these were actually 24.3 inch tires). The third performance
> calculator came up with this:
>
> (1) 1/4 Mile ET of 12.23
> (2) 1/4 Mile Top End Speed of 106.52 mph
> (3) Ideal Gear Ratio of 4.63
> (4) 1/8 Mile ET of 7.79 seconds
>
> This data is surprisingly accurate. Compare the results to what the car
> actually did:
>
> Predicted ET of 12.23....actual ET of 12.151
> Predicted top end speed of 106.52 mph....actual top end speed of 106.25
> mph
> Suggested ideal gear ratio of 4.63....actual gear ratio is 4:57
> Predicted 1/8 mile ET of 7.79 seconds....actual ET of 7.602 mph
>
> OK, now that I've demonstrated how accurate the three sites are with a
> known vehicle's performance, let's now use the first site, Simple
> Horsepower Calculator, the one that seems to have nailed my car's hp
> pretty darn well, and see how Dennis' predictions of 8.48 seconds and
> 157 mph come out:
>
> Again, this site has open boxes where you can enter data:
>
> (1) Vehicle Weight (including driver weight)
> (2) 1/4 Mile ET
> (3) 1/4 Mile Trap Speed
>
> I entered the Chevy's 4900 lb. estimated weight (4700 lbs. + 200 lb.
> driver) and Dennis' 8.48 ET and the 157 mpg figures. The calculator
> came up with these outrageous results:
>
> (1) Based on the ET, 1588 hp!!
> (2) Based on the mph, 1480 hp!!
>
> I'm told the Chevy's incredible battery pack can deliver 3800 amps at
> around 170 volts, or a whopping 646 kw!
> Now, though that's a huge amount of delivered power, in the real world
> of DC motors at BIG amps, a best case scenario is figuring 75%
> efficiency, so for every hp generated (746 watts) the motors will
> actually suck 1000 watts....this comes in at 646 hp, tops.
>
> OK Dennis, where do you come up with at the least, 1480 hp? Where do
> you get 157 mph? Where on earth, do you get 8.48 seconds?
>
> At the National Drivetrain site, I entered the Chevy's 4900 lb.
> estimated weight (4700 lbs. + 200 lb. driver) and the more realistic
> 646 hp figure, plus 5000 rpm and 26 inch tires. The calculator came up
> with these results:
>
> (1) 1/4 Mile ET of 10.98
> (2) 1/4 Mile Top End Speed of 119.18 mph
> (3) Ideal Gear Ratio of 3.25
> (4) 1/8 Mile ET of 7 seconds
>
> Note, that if I'm off on the rpm or the tire size, it still doesn't
> change the ET or the MPH figures. Of course, a scorching 10.98 would
> make us all proud! However, an 11 second ET is a far cry from a
> predicted 8.48 seconds! Likewise, the 119 mph is a far cry from the
> predicted 157 mph! If the battery pack can't actually deliver the full
> 3800 amps, or if at that level the voltage falls below 170, or if both
> are on the optimistic side of things, then the actual horsepower will
> be less. With 3600 amps from twin Zilla 1800 amp controllers and
> keeping the pack sag to 170 volts, it comes in at 612 kw, and the car
> would run an 11.17 @ 117 mph. Still killer, but approaching 3 seconds
> slower and a full 40 mph shy of Dennis' predictions.
>
> Dennis, care to correct me on any of this? Did you slip up with your
> figures, or were you merely using Neutrino logic and cold fusion
> calculations here?
>
> See Ya.....John Wayland
>
>
>
>
--- End Message ---
--- Begin Message ---
[EMAIL PROTECTED] wrote:
> I always thought that the main failure mode happened when you were pushing
> the throttle. Can the controller fail full on when your just stopped and
> have your foot off the throttle?
Yes, it can. For a worst-case example, some people keep their controller "on"
while charging (I don' need no steenkin' contactors!) The voltage during
charging gets much higher than normal. Transistors can suddenly fail "on"
from excessive voltage alone. And if they do, your motor goes to full
throttle! The *bang* will follow very shortly.
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 [EMAIL PROTECTED]
--- End Message ---
--- Begin Message ---
Osmo Sarin wrote:
> To help to shift on the fly: when the clutch pedal (without a clutch)
> or a hand switch is pressed, or gear is shifted to neutral, the
> controller would ignore the acc pedal signal and set motor rpm to same
> as gearbox rpm. Maybe the speedometer sensor signal could be used to
> give the gearbox rpm?
>
> Would it be very complicated construction? Easier in AC or DC system?
It's not particularly complicated. All it adds is a couple of rpm sensors, a
circuit to take the difference between them to produce an error signal, and
an output that drives the controller's speed control input to make this error
zero. Switches would activate this circuit when you pressed the clutch. Other
switches would sense what gear you were pushing the gearshift lever towards.
One challenge is that if you don't have a regen controller, you can speed up
the motor quickly, but can only let it coast down in speed. So downshifts are
easy (3rd > 2nd), but upshifts (2nd > 3rd) are slow. A simple way to fix this
is to use your traction motor to also run something like a power steering
pump, power brake vacuum pump, or alternator for 12v power. These loads would
make the motor slow down much faster.
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 [EMAIL PROTECTED]
--- End Message ---
--- Begin Message ---
Victor Tikhonov wrote:
> Have no idea how one would adjust frequency (I should say rotation
> speed) of a DC motor and make it stable. Using analog throttle
> input seem too coarse - how does one set the rotation to, say,
> 3,548 min^-1 for easy shift if the tranny is going this fast?
> One more AC setup advantage :-)
It's done closed-loop. Exactly the same as you do in an AC controller with an
induction motor. Virtually every tape deck, CD player, disk drive, and
anything else where they need a motor to run at a precise speed does it this
way. You'll find they are as often DC motors as AC motors.
You need some kind of speed sensor to know how fast the motor is actually
turning. Your circuit compares the desired speed to the actual speed to get
an error signal. This error signal drives the motor faster/slower until the
error is zero.
Get yourself a few little DC PM motors, and an opamp like an LM324, and a few
other simple parts as shown. Here comes another bad old ASCII schematic; view
it with a fixed-width font.
___________________________________________________
| 100k 100k |
|__/\/\_____/\/\__ |
| 1uf | |
|____||__| +V |
| || | | |
| |\ | ____|/ c Q1 NPN |
|__|-\ | | b |\ e 2N4401 | speed
100k | \__|__| |___________ drive | sensing
input__/\/\_________| / 1/4 | | | motor | motor
| | |+/LM324 |____|/ e Q2 PNP _|_ _|_
_|_ > |/ opamp b |\ c 2N4403 / \ _ _ _ / \
1uf ___ > | \___/ \___/
| > 100k gnd | |
| | amplifier gnd gnd
gnd gnd
All motors are just little PM DC motors, like you find in toys. The "drive
motor" simulates your traction motor. The "speed sensing motor" is being used
as a generator, to generate a voltage proportional to rpm.
To begin, have no connection between the drive motor and speed sensing motor.
Connect some voltage to the input (say, from a pot connected between +V and
ground). This is your throttle; adjusting its voltage up/down makes the motor
run faster/slower. 0v is stopped; +V volts is full speed.
Now, add a 3rd PM DC motor; this one connected between the input and ground.
The *speed* of this motor sets the input voltage. This motor would be
connected mechanically to your vehicle's drive shaft or something that tells
how fast the wheels are turning. Connect the shafts of drive motor and speed
sensing motor (with a bit of plastic tubing or wire insulation, for example).
What you will find is that whatever speed you spin the input motor, the drive
motor will run at exactly the same speed. It behaves as if there is a
mechanical connection between the two of them!
It works this way because the opamp adjusts its output so its + and - inputs
are at the same voltage. This only happens when the input motor and speed
sensing motor produce the same voltage, which means they are at the same
speed.
All resistor values are equal, so input speed = output speed. If you pick
resistor ratios to match your transmission gear ratios, then the motors run
with precisely that speed ratio.
For an EV, the drive motor is far larger, and the amplifier is your
controller. It doesn't matter if they are AC or DC.
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 [EMAIL PROTECTED]
--- End Message ---
--- Begin Message ---
Paul G. wrote:
> I was wondering what is the typical current to float charge 6v golf
> cart batteries. My father wants to store his golf cart over the summer,
> around 7 months between the time my parents leave AZ to the time they
> return. Is float charging a GC battery at 6.6 to 6.7 volts a really bad
> idea? It seems like a better idea than letting them sit unattended over
> an AZ summer.
"Float" charging means connecting the batteries to a constant voltage source,
and letting them draw whatever current they want to. The float voltage should
be 2.2 to 2.3v/cell, which is 6.6-6.9v/cell for a 6v battery.
There is a range of voltages to deal with temperature and the age of the
batteries. For new batteries at 25 deg.C (77 deg.F), use 2.25v/cell. As the
battery ages, and as the temperature rises, reduce the voltage accordingly.
On float, the batteries will draw very little current; well under 1 amp. A
tiny little "wall wart" type power supply is all it takes.
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 [EMAIL PROTECTED]
--- End Message ---
--- Begin Message ---
The power point I saw was at 14.4 volts,
for a single V28 Milwaukee power pack.
And just a touch under 1200 watts.
Lets keep in mind that Glowing reports and support for our sponsors this
Christmas Tool buying season.
Is just plain good buisness.
Best cordless pack I have seen. For sure
Madman
----- Original Message -----
From: "BadFishRacing" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Monday, December 19, 2005 8:32 AM
Subject: Re: Predictions for the Monster Garage '62 Electric Chevy?
> I've tried to calculate the ability of ONE pack, but I guess I'll ask.
>
> If each pack is good for 1200 watts, is that 100amps @12V (sagged down
from
> 28V)?
>
>
> BadFishRacing
>
> ----- Original Message -----
> From: <[EMAIL PROTECTED]>
> To: <[email protected]>
> Sent: Monday, December 19, 2005 6:44 AM
> Subject: Re: Predictions for the Monster Garage '62 Electric Chevy?
>
>
> > John,
> >
> > As I said previously, the packs (as they are configured) are only good
> > for a peak of 1.2kw each x 384 pcs.= 612 Hp.
> > To put it another way 3200 amps at 144 volts total. I believe the
> > cells are capable of more but the configuration we used was never
> > intended to be punished the way we are treating them. When you see the
> > show you, and others, will immediately see the weak link in the battery
> > system. I base my performance numbers on the above figures because I
> > know them to be attainable, (at least for short bursts).
> >
> > Assuming I can get the cells for my personal use let's try to get to
> > Dennis' numbers.
> > Here's what we know.
> >
> > 384 pc battery pack = 612 peak hp and 1000lbs, (including very heavy
> > interconnects)
> > We strip the cells from their heavy casings and replace connections
> > with more efficient design
> > Revised battery pack = 612 peak hp and 400 lbs
> > OJ 2 chassis with 12 Lemco's and no battery or driver = 750lbs
> > Non beer drinking Driver= 100 lbs
> > Total GVW = 1250 lbs.
> > Peak Wheel HP = 460 hp
> >
> > Now we're getting somewhere.
> >
> > My calculator shows 8 flat is feasible. If I can keep the brush gear
> > from melting, the front end on the ground at least once in a while,
> > etc, etc.....
> >
> > I think it would take the reactor from the Ronald Reagan Aircraft
> > Carrier to get this 62 Chevy as it is into the 8's.
> >
> > Shawn
> >
> >
> > -----Original Message-----
> > From: John Wayland <[EMAIL PROTECTED]>
> > To: [email protected]
> > Sent: Sun, 18 Dec 2005 21:41:31 -0800
> > Subject: Predictions for the Monster Garage '62 Electric Chevy?
> >
> > Hello to All,
> >
> > [EMAIL PROTECTED] wrote:
> >
> > >With 2 zillas and the >power to feed them from the lithium pack the
> > 4700lb chevy with all the good >suspension work should run 8.64 seconds
> > in the qt.mi. at 157mph.I would not >expect this in your 1st run out
> > but after 5-8 passes. These #s come from the VERY >predicitable
> > Speedworld horsepower calc. on their site, but do not include my
> > >multipiler. With that multiplier in the equa.you will run 8.48 in the
> > qt.mi. >What a difference a little NITRO makes!!!! Dennis Berube
> > > >
> >
> > Whoa, Dennis' ET predictions for the Monster Garage project Chevy sure
> > seem 'optimistic'! I respect Dennis, he's a great competitor, a friend,
> > and quite a character, too! He's still the top dog as far as having the
> > quickest electric ET, too. However, as excited I am about the rad one
> > week conversion that friends Rudman and Lawless did, these guys, the
> > ones that helped build the thing, both feel low to mid 13's are more
> > realistic, certainly not 12's....it's too heavy and there's just not
> > enough raw power to get the job done.
> >
> > To investigate Dennis' predictions, I've done some research of my own,
> > and offer the findings as balance to what I feel is a wild prediction
> > of performance I personally, don't think is even close to being
> > correct...no offense is intended. I have tried very hard to keep past
> > predictions of performance as accurate as possible, whether it's my own
> > car, or someone else's. As an example, when Matt Graham first contacted
> > me more than a year ago about his proposed twin motor electric Nissan
> > 240SX, I predicted it would run easy 14's, and that it could get into
> > the 13s'....he ran a 14.2 first time out. I've been pretty much right
> > on the mark with my car all along, too.
> >
> > OK, here we go.....I plugged in a known performance spec list from my
> > own White Zombie, at three different 1/4 calculator sites. The first
> > one, Simple Horsepower Calculator, is at:
> >
> > http://www.dsm.org/tools/calchp.htm
> >
> > This site has open boxes where you can enter data:
> >
> > (1) Vehicle Weight (including driver weight)
> > (2) 1/4 Mile ET
> > (3) 1/4 Mile Trap Speed
> >
> > I entered my accurate data of 12.151 for the ET and 106.25 for the mph,
> > and my estimated data of 2550 lbs. for vehicle (2350 lbs. & 200 lb.
> > driver) weight. Historically, I've been within 50 lbs. on my electric
> > conversion weights. The calculator came up with this:
> >
> > (1) Based on the ET, 281 hp
> > (2) Based on the mph, 239 hp
> >
> > Since drag racing EVs typically have a lower top end speed as does a
> > gasser running the same ET, I tend to lean toward the mph based hp
> > levels.
> >
> > The second site, Horsepower Calculator, is at:
> >
> > http://www.s-series.org/htm/calc/hpcalc.htm
> >
> > This site has open boxes where you can enter data:
> >
> > (1) Known 1/4 mile ET
> > (2) Vehicle Weight (including driver weight)
> > (3) 1/4 Mile MPH
> > (4) 60 ft. Time
> >
> > Note that this site adds a box for the 60 ft. time, which I feel really
> > improves the accuracy.
> >
> > I entered the same accurate data of 12.151 for the ET, 106.25 for the
> > mph, and added 1.59 for a 60 ft. time, plus the estimated data of 2550
> > lbs. for vehicle (2350 lbs. & 200 lb. driver) weight. The calculator
> > came up with this:
> >
> > (1) RWHP (rear wheel horsepower) from entered ET of 280.93 hp
> > (2) RWHP from MPH of 238.71 hp
> > (4) Break hp from ET of 337.116 hp
> > (5) Break hp from MPH of 286.452 hp
> >
> > The third calculator site, National Driveline, is at:
> >
> > http://www.nationaldrivetrain.com/calcs/dragcalc.html
> >
> > This site has open boxes where you can enter data:
> >
> > (1) Vehicle Weight (including driver weight)
> > (2) Vehicle hp
> > (3) RPM through the finish line
> > (4) Tire diameter
> >
> > I used the same 2550 lbs. vehicle weight, and since the 239 hp from the
> > first site and the 238.71 hp that the second site were pretty much
> > identical, I rounded it to 240 hp, 6900 rpm from our tach data and
> > calculations using the rear end ratio and tire diameter, and 24 inches
> > as the current diameter of the Goodyear Drag Radials (before we burned
> > them down, these were actually 24.3 inch tires). The third performance
> > calculator came up with this:
> >
> > (1) 1/4 Mile ET of 12.23
> > (2) 1/4 Mile Top End Speed of 106.52 mph
> > (3) Ideal Gear Ratio of 4.63
> > (4) 1/8 Mile ET of 7.79 seconds
> >
> > This data is surprisingly accurate. Compare the results to what the car
> > actually did:
> >
> > Predicted ET of 12.23....actual ET of 12.151
> > Predicted top end speed of 106.52 mph....actual top end speed of 106.25
> > mph
> > Suggested ideal gear ratio of 4.63....actual gear ratio is 4:57
> > Predicted 1/8 mile ET of 7.79 seconds....actual ET of 7.602 mph
> >
> > OK, now that I've demonstrated how accurate the three sites are with a
> > known vehicle's performance, let's now use the first site, Simple
> > Horsepower Calculator, the one that seems to have nailed my car's hp
> > pretty darn well, and see how Dennis' predictions of 8.48 seconds and
> > 157 mph come out:
> >
> > Again, this site has open boxes where you can enter data:
> >
> > (1) Vehicle Weight (including driver weight)
> > (2) 1/4 Mile ET
> > (3) 1/4 Mile Trap Speed
> >
> > I entered the Chevy's 4900 lb. estimated weight (4700 lbs. + 200 lb.
> > driver) and Dennis' 8.48 ET and the 157 mpg figures. The calculator
> > came up with these outrageous results:
> >
> > (1) Based on the ET, 1588 hp!!
> > (2) Based on the mph, 1480 hp!!
> >
> > I'm told the Chevy's incredible battery pack can deliver 3800 amps at
> > around 170 volts, or a whopping 646 kw!
> > Now, though that's a huge amount of delivered power, in the real world
> > of DC motors at BIG amps, a best case scenario is figuring 75%
> > efficiency, so for every hp generated (746 watts) the motors will
> > actually suck 1000 watts....this comes in at 646 hp, tops.
> >
> > OK Dennis, where do you come up with at the least, 1480 hp? Where do
> > you get 157 mph? Where on earth, do you get 8.48 seconds?
> >
> > At the National Drivetrain site, I entered the Chevy's 4900 lb.
> > estimated weight (4700 lbs. + 200 lb. driver) and the more realistic
> > 646 hp figure, plus 5000 rpm and 26 inch tires. The calculator came up
> > with these results:
> >
> > (1) 1/4 Mile ET of 10.98
> > (2) 1/4 Mile Top End Speed of 119.18 mph
> > (3) Ideal Gear Ratio of 3.25
> > (4) 1/8 Mile ET of 7 seconds
> >
> > Note, that if I'm off on the rpm or the tire size, it still doesn't
> > change the ET or the MPH figures. Of course, a scorching 10.98 would
> > make us all proud! However, an 11 second ET is a far cry from a
> > predicted 8.48 seconds! Likewise, the 119 mph is a far cry from the
> > predicted 157 mph! If the battery pack can't actually deliver the full
> > 3800 amps, or if at that level the voltage falls below 170, or if both
> > are on the optimistic side of things, then the actual horsepower will
> > be less. With 3600 amps from twin Zilla 1800 amp controllers and
> > keeping the pack sag to 170 volts, it comes in at 612 kw, and the car
> > would run an 11.17 @ 117 mph. Still killer, but approaching 3 seconds
> > slower and a full 40 mph shy of Dennis' predictions.
> >
> > Dennis, care to correct me on any of this? Did you slip up with your
> > figures, or were you merely using Neutrino logic and cold fusion
> > calculations here?
> >
> > See Ya.....John Wayland
> >
> >
> >
> >
>
--- End Message ---
--- Begin Message ---
I havn't felt the need to brace mine. It handles better than the original
due to the more even weight distribution. I pushed it fairly hard round
Anglesea race circuit. The easy brace, that doesn't get in the way of
anything, is between the front wishbone mounts.
Paul Compton
www.sciroccoev.co.uk
www.morini-mania.co.uk
www.compton.vispa.com/the_named
----- Original Message -----
From: "Ken Albright" <[EMAIL PROTECTED]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, December 19, 2005 2:34 PM
Subject: VW body reinforcement
My 86 Scirocco conversion is finally under way. Talking to the local VW
guys, they are recommending crossbars to reinforce the body at the top
and bottom of the front struts and the top of the rear shocks. The upper
ones will get in the way of battery placement.
Anyone do this to your unibody conversion? More important, anyone wish
they had?
Thanks
Ken
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
At 06:34 AM 12/19/05 -0800, you wrote:
My 86 Scirocco conversion is finally under way. Talking to the local VW
guys, they are recommending crossbars to reinforce the body at the top
and bottom of the front struts and the top of the rear shocks. The upper
ones will get in the way of battery placement.
Anyone do this to your unibody conversion? More important, anyone wish
they had?
Not necessary. Our #1 Voltsrabbit has been in service since 1991. Since
we used this as a teaching car to take apart and put together for
workshops, we had repeated opportunities to check it over for any signs of
alarming wear, tweaking, stress, etc. Nada.
Handling is very good (better than stock - it keeps all four wheels on the
ground in corners) even on twisty mountain roads.
Mike Brown
Electro Automotive POB 1113 Felton CA 95018-1113 Telephone 831-429-1989
http://www.electroauto.com [EMAIL PROTECTED]
Electric Car Conversion Kits * Components * Books * Videos * Since 1979
--- End Message ---
--- Begin Message ---
The yahoo archive seems to be in trouble. Most of the time it's not alowing
you to see messages due to having exceeded the bandwith limit.
Paul Compton
www.sciroccoev.co.uk
www.morini-mania.co.uk
www.compton.vispa.com/the_named
--- End Message ---
