EV Digest 6704
Topics covered in this issue include:
1) Re: [EV] RE: Issues involved in a controller bypass? (ForkenSwift)
by "Jack Riggi" <[EMAIL PROTECTED]>
2) Re: DOD question - new/old debate
by Victor Tikhonov <[EMAIL PROTECTED]>
3) RE: Light EV, controller/motor?
by "Randy Burleson" <[EMAIL PROTECTED]>
4) Re: OT: Generator and UPS
by Dennis Foulke <[EMAIL PROTECTED]>
5) Re: corvette conversion
by Jack Murray <[EMAIL PROTECTED]>
6) Re: DOD question - new/old debate
by Danny Miller <[EMAIL PROTECTED]>
7) Re: Motor, controller & battery recommendations?
by Jeff Shanab <[EMAIL PROTECTED]>
8) cheap batts for the very patient? :-0
by <[EMAIL PROTECTED]>
9) Minn Kota Chargers?
by <[EMAIL PROTECTED]>
10) Re: DOD question - new/old debate
by Danny Miller <[EMAIL PROTECTED]>
11) Re: financing an EV
by "Tom Carpenter" <[EMAIL PROTECTED]>
12) Re: cheap batts for the very patient? :-0
by Danny Miller <[EMAIL PROTECTED]>
13) Re: DOD question - new/old debate
by "FRED JEANETTE MERTENS" <[EMAIL PROTECTED]>
14) Range question
by "Freddie Hartsell" <[EMAIL PROTECTED]>
15) NEDRA gets a twist of Lime
by Chip Gribben <[EMAIL PROTECTED]>
16) RE: We're Not Screwed (Graphic)
by Mike Willmon <[EMAIL PROTECTED]>
17) Re: DOD question - new/old debate
by Ralph Merwin <[EMAIL PROTECTED]>
18) Re: Motor, controller & battery recommendations?
by "Marty Hewes" <[EMAIL PROTECTED]>
19) Re: Light EV, controller/motor: Lynch motor
by tt2tjw <[EMAIL PROTECTED]>
20) Re: [EV] RE: Issues involved in a controller bypass? (ForkenSwift)
by "Dave Wilker" <[EMAIL PROTECTED]>
21) Re: DOD question - new/old debate
by Rob&Amy Smith <[EMAIL PROTECTED]>
22) Re: cheap batts for the very patient? :-0
by Rob&Amy Smith <[EMAIL PROTECTED]>
--- Begin Message ---
I would like to thank the people for helping me with how things work , you
really helped clear things up on how it works . Sorry I did not answer
sooner but I just got a job out of town & did not have internet connecton
were I was , got firerd today now have more time but no money to convert my
truck to ele. Does any body know how many amps 400watts 12v are, & how many
watts there are in 130 amps . am working on a new project with wind power to
help recharge batts. I am sure one of you will know . Thanks again Jack
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Saturday, April 21, 2007 10:57 PM
Subject: Re: [EV] RE: Issues involved in a controller bypass? (ForkenSwift)
Jack Riggi wrote:
I am really new on this ele. thing but what are you talking about? what
are you trying to do? I don't even know what a controller or a bypass is?
Hi Jack,
It's not too hard to understand. In an electric car, you have a motor,
batteries, and a controller. The controller is like a big light dimmer; it
controls your speed. Without it, your "gas pedal" would just be an on-off
switch (full speed or nothing)!
The controller is usually your weakest link; it limits how fast you can go
and how fast you can accelerate. This is due to cost. A wimpy controller
is around $500; a good one $1000, and a really fast on $2500.
With a simple DC motor, you can get "maximum power" by just bypassing the
controller -- i.e. switching the motor *directly* to the batteries with no
controller at all. You get tire-spinning (axle breaking, battery bursting,
motor murdering) performance without an expensive high-power controller.
So there is a strong interest in just using a big switch to avoid having
to buy an expensive high-power controller.
So, most of these discussions are about finding ways to add a bypass
switch without breaking something in the process.
--
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 ---
Peter VanDerWal wrote:
Seems to me the best way would be to have TWO readings, perhaps side by
side bar graphs.
One indicates remaining capacity at average current levels, and the other
indicates remaining capacity at the existing current draw.
Thanks Peter,
No matter how you slice it, gadget will never show how far you can
drive, one reading or ten readings. Best it will do is show
how much you've spend and how much remains *if* you keep spending
at the same rate which you generally may not. That's the source
of the problem.
It is not a problem to estimate range based on past (1 min, 10 miles,
whatever I choose) history. Problem is you're either forced to drive
the same way if you want believe the readout, or accept the fact that
it may be way off if you'll drive differently (which is not always
up to you).
Again I have only one 3 digit display for relative SOC (+ analog bar).
I don't really expect clear answer from anybody, there is simply
none exist. Will do my best.
Victor
--- End Message ---
--- Begin Message ---
Thanks for all the excellent responses, all.
> If you are going that size, go for BB600's instead at about 1/3 the
> cost and about the same amps, at least as far as you need at about
800.
That price doesn't worry me, but I was under the impression that BB600s
and their Marathon cousins were becoming difficult to find?
> Or go Trojan 12vdc 100-130 amphr batts to get the range you want. 6
would
> be 360-420 lbs and give you almost twice the range as the AGM's at
much
> less cost.
At significant cost to acceleration, no?
> ...motor and controller -- usage is basic commute, 30 miles round trip
--
> highway-capable preferred but not absolutely necessary.
> Go either contactor controller or a Altrax 7245, $475
That's a pretty excellent price point, Jerry, over $200 lower than I
could find it for.
> The 85lb L91- D+D ES31 are the same starting point for the Killa-cycle
> so should easily do you.
Reasonable cost, as well:
http://www.electricvehiclesusa.com/product_p/mo-l91-4003.htm
> > The plan is to slide under 1000 pounds (<400 chassis, <100 body,
> > <400 batteries, <150 motor, and precious little else), fantasy
> target is actually 800.
> Ewoody body/chassis 235 lbs, motor 50lbs, Too heavy VW front
suspension
> 165lbs, wheel/tire 25lb each. It weighed under 900lbs with a 36vdc
pack
> it mostly used. Another 100 lbs could be saved by using a lighter
front end.
Thanks for the additional data on the E-Woody, Jerry.
> Consider wood/epoxy for your body/chassis...
I may use composite/wood for some elements, but am committed to have a
basic steel tubeframe in which to roll (literally, if necessary!). I'll
prototype in PVC to minimize rework and expense in welding wire and
HREW.
Randii
-----Original Message-----
From: jerryd [mailto:[EMAIL PROTECTED]
Sent: Wednesday, April 25, 2007 1:33 PM
To: ev@listproc.sjsu.edu
Subject: Re: Light EV, controller/motor?
Hi Randii and All,
----- Original Message Follows -----
From: "Randy Burleson" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Subject: Light EV, controller/motor?
Date: Wed, 25 Apr 2007 07:52:38 -0700
>I'm planning a small, simple 3-wheeler EV (half-on or smaller, see
>below), and I'm at a point where I need to plan budget, and that means
>picking a motor (series) and controller -- I'm pretty committed to AGMs
>for high output and low weight.
You may get high output but low weight is not a AGM strong point
as they have only about 85% of the range compared to a good flooded
batt. If you are going that size, go for BB600's instead at about 1/3
the cost and about the same amps, at least as far as you need at about
800.
Or go Trojan 12vdc 100-130 amphr batts to get the range you
want. 6 would be 360-420 lbs and give you almost twice the range as the
AGM's at much less cost. Especially as you will need buddy pairs AGM's
to get the range you need..
FWIW, I'm willing to pay a fair price for
>motor and controller -- no need to dumpster-dive, but no need to
>over-spend. My usage is basic commute, 30 miles round trip --
>highway-capable preferred but not absolutely necessary.
Go either contactor controller or a Altrax 7245,
$475 or a combo, starting on the Altrax and switching quickily to the CC
for more power. Also several 1000 amp 48vdc controllers out there that
will do the job well.
The 85lb L91- D+D ES31 are the same starting point for the
Killa-cycle so should easily do you. I'd even go smaller like the 50 lb
A-89, ES21-$475 at your weight. The E woody has a GE that size. The
Freedom has either the L91 or
2- A89's at 1350 lbs. Prices D+D who are the original ADC owners,
company after they sold their ADC name, 8" and larger line.
The plan is to slide under 1000 pounds (<400
>chassis, <100 body, <400 batteries, <150 motor, and precious little
>else), fantasy target is actually 800.
Ewoody body/chassis 235 lbs, motor 50lbs, Too heavy VW front
suspension 165lbs, wheel/tire 25lb each. It weighed under 900lbs with a
36vdc pack it mostly used. Another 100 lbs could be saved by using a
lighter front end.
Consider wood/epoxy for your body/chassis, light, strong, looks
great done clear, easy to build, easy to throw away if you screw up,
great to learn with. Especially on your first designs as they only cost
a couple hunderd bucks each. I like to build a quick and dirty first one
to learn how to do it right, then build the second correctly to a better
finish. If nothing else, mock it up in ply to see if everything fits,
ect.
>
>Eight 12V Optima D34 Yellow Top batteries total ~352 pounds. I'm
>planning 96V, but I might be able to get by with a 72-volt pack. I know
>that Jerry made the E-Woody work with a 48V pack, and I'm shooting for
>a similar weight , but I imagine that I'm more aggressive with the
>accelerator. (http://www.1st-optima-batteries.com/ tells me that YT
>D34s are 12V, 55 AH, 120 reserve minutes; 10x6.8x7.8" <Height includes
>1" terminals>; 43.8 lbs;
>$174.95 each, includes shipping) Low weight trumps cost per watt, but
>I'll miss the ability to equalize. I plan to use a bank of individal
>chargers to keep from gassing about a grand worth of AGMs.
You won't be able to use that amperage as you will just burn
off the tire so no reason for AGM's. And they are not lightweight for
their range and expensive to charge.
>
>A potential point of complication is that I'm going to start with
>chain-drive and no transmission... I'm not sure if I can get the
>acceleration and range of speed I desire, but I will try.
Go with belt drive or your will quickly understand why you
should have, too much messy, greasy work which is what I came to EV's to
get away from. Only homebuilt EV's use transmissions and you certainly
don't need one so just put a belt from the motor to the rear wheel like
the Sparrow, ect.
Jerry Dycus
>
>I'm open to suggestions on appropriate motors (and vendors!)... I'm
>thinking a 6.7" should scoot fairly well in such a lightweight rig, but
>have a hard time breaking my bigger-is-better hot-rod habit, and am
>also looking at 8"
>motors. I'm entirely baffled as to how big a controller I need... I've
>studied the EV Album and there's IMHO a lack of consensus for what is
>needed and what would just be nice to have.
>
>Comments?
>
>Randii
>
--- End Message ---
--- Begin Message ---
Your generator probably has a square wave inverter to generate the 115
VAC. I am guessing that the two USP systems did not like the square
wave signal while everything else was happy with the signal. Next
time you fire up the generator, hook an oscilloscope across the line and
see what type of AC signal you have.
Dennis Foulke
Michaela Merz wrote:
Hello:
Just a short question for you folks: We had a power outage today due to a
bad thunderstorm. The emergency generator went on and it would have been
no problem, but the UPS systems for our computers went crazy.
The generator is rated at 25KW, the two UPS systems are small two computer
units. Voltage measured at the outlet was 122-124 V at 59.8-61.0 Hz.
However, the UPSs didn't accept that as 'good' voltages and went into
battery mode. For a few minutes in between, they switched to 'normal'
mode but sure enough, after just 2 or 3 minutes, they went back to 'beep'
.. 'beep' .. 'beep'.
As soon as power was restored and the generator shut itself off, both UPSs
were happily sitching back to 'all ok'.
I am puzzled as everything else worked just fine, TV, other electronics,
only the UPSs had a problem. Any ideas?
Michaela
--- End Message ---
--- Begin Message ---
Hi Steve, as you know I think the vette is a good choice although my
choice would be the C4. The AC55 looks like a good motor. It doesn't
have the best power/weight, but not many other options for AC.
The lack of feedback means you are likely a trail blazer here, which is
a good thing, who needs another lead-sled pickup truck :)
Not to discount the value added of electroauto but it's a pricey package.
If you want to get it done quickly, that is probably the best option.
I'm certainly interested in seeing the progress, but sure to get a
wepage going for it.
Cheers,
Jack
Steve wrote:
Hi,
Just put down a deposit on a 1981 donor corvette, so now I need to
get busy. I didn't receive any feedback on the questions concerning
the Solectria AC55 motor/controller, or electroauto.com.
Any/all comments appreciated, either via the list, or by private
email. I would like to place an order within a week or 2 at most.
---
tia,
Steve
[EMAIL PROTECTED]
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
From the way it's been described, e-meter uses an incorrect
interpretation of Peukert's.
Drawing 1AH at a high rate with a 2x Peukert factor does not remove 2AH
from the battery.
My interpretation is that it means the battery can't sustain this
current when it's more than half discharged, thus the battery's
effective capacity is half the ultimate capacity. Attempting to draw
more current than Peukert's allows at the current SOC will bring down
the cell voltage below 1.75V per cell.
eMeter will be inaccurate when you draw current than is different than
your history.
On one hand, if you drew current previously at a high rate, it will show
an artificially low capacity remaining when you switch to driving at
lesser current.
On the other hand, if you use part of your capacity at a low rate then
switch to a high rate, it will tell you there is capacity left even when
the battery is incapable of supplying the current you're try to use.
Everyone asks how a batt gauge could be made where it won't go up and
down with current usage. Unfortunately, this is a problem inherent to
the way the batt works and the inconsistency of the driving load and
it's essentially impossible to get around this while providing an
accurate estimate. It works as long as past usage is an indication of
future needs for the remainder of your drive. Sometimes that is true.
Sometimes it is not. You may have one leg of your trip on a highway and
the other through a neighborhood. One leg may be downhill and the other
uphill- in which case range & capacity estimates are impossible. To
estimate the range, you have to know where you're going, and the
computer can't know that without detailed navigation data.
Danny
Paul wrote:
On Apr 26, 2007, at 9:32 AM, Victor Tikhonov wrote:
E-meter owners - is this how SOC is displayed to you?
The e-meter uses the 20 hour battery capacity and the Peukert's
exponent to calculate the batteries Peukert's capacity (the capacity
at a 1 amp discharge rate in theory.) As you drive it raises the amps
you are using at any point (several times a second anyway) by the
Peukert's exponent, converts that to amp hours (for instance, if the
e-meter sampled only once per second it would divide the adjusted
amps by 3600 to get amp hours), and subtracts that from the Peukert's
capacity. This system results in a battery "fuel" gauge that doesn't
go back up when you remove the load. It also results in a fuel gauge
that considers your past driving (on that charge) to be an indicator
of your future driving on that charge.
--- End Message ---
--- Begin Message ---
Another thing about automatics. at lease the GM ones.
The pump pressure is varied to effect the firmness of the shift.
in pre-96 vehicles this was done off of engine vacuum. without the
engine vacuum to modulate the pressure it hammers on shifting. This is
not the vacuum used to shift in the even older transmissions, we are
talking about pump pressure.
After 96ish the ECM sends a PWM signal to the tranny to regulate the
pressure. It uses the TPS,Map sensor(expensive vacuum sensor), and speed
to determine the pressure needed. Drag racers with these newer trannies
use a little black box to supply the signal to allow firmer ,quicker
shifts with highly modded engines (see Summit racing)
Since you won't otherwise need the ECM, it may be a good idea to
make sure the auto tranny you have doesn't need some extra signals.
of course the cool part is that with a PIC micro you can
up-shift,downshift, adjust pump pressure and select torque converter
lock/unlock.
--- End Message ---
--- Begin Message ---
Anyone every been crazy enough to build an EV pack out of AA sized cells? I
assume pack construction would drive you insane :-) Maybe the scooter/bike
guys then?
These guys seem to have some ridiculously cheap deals ($100 min order though I
think) on surplus small cells:
http://www.73.com/a/0658.shtml
Sanyo KR-1700E NiCad $0.23 ea, ~14k in stock
1700mAh 4/3A, discharge curves up to 8C, charge curves up to 1.5C
http://www.73.com/specs/th720.pdf
50 strings of 120 would yield 89Ah @ 144V, Imax ~680A, Rint ~17mOhm, 555 lbs
plus pack construction for $1380 plus materials. Only 12000 solder points ;-)
2x18650 LiIon cells in qualcomm packs (used) $0.89 ea, 13,500 in stock
1200mAh @7.2V
8x1.7Ah NiMh cells in HP laptop packs (new) $0.69 ea, 5600 in stock
1700mA @ 9.6V
1.2Ah Duracell/Toshiba NiMh AAs (new 95-97 vintage) $0.25 ea, 25k in stock
Anyone ever dealt with these guys? Does radio shack carry a 6000 AA carrier
sled? :-)
Rob
--- End Message ---
--- Begin Message ---
Anyone ever look at using Minn Kota chargers for a parallel charging setup?
As I recall the biggest issue folks had been having with Soleil's and the like
seemed to be related to vibration and environment induced failures. Is that
still the case? These are probably heavier, but claim to be AGM friendly and
vibration/shock/weather/salt resistant as they're meant for onboard marine use.
In particular I was looking at the MK 440, which has 4 independent banks at 10A
each, 3 stage charging and temperature compensation. They seem to indicate its
ok to hook these up to series connected batteries, so I assume each bank is
isolated but there's not much tech info. After the rebate and shipping, it
seems like you can find these for about $250. For a 144V pack it works out to
about 67.6 lbs and $750. Not too bad seems like. There is also a 15A per bank
version which would put it up to ~$1150 and 93 lbs.
Any thoughts?
Thanks,
Rob
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--- Begin Message ---
Actually I believe averaging your past usage is not a best estimate.
For example, say you use 120 amps to pick up from a stop but only 50
amps average. I believe your capacity is limited by your peak needs,
not by the average usage. Trying to draw high currents at a SOC below
the Peukert capacity for that current will usually bring it below
1.75V/cell unless it's so brief that the batt's surface charge will
smooth it out. So say the past road is exactly like what you've been
doing, same stoplights about the same distance apart. The 50 amp
capacity is not useful because you'll only be able to cruise, the pack
will sag below min voltage trying to come off a stop. So it sounds to
me like the 120 amp capacity predicts the range because if history tells
you anything it tells you sometimes you need 120A. However, drawing
10AH at a 50 amp avg- sometimes 20A, sometimes 120A- should deduct only
10AH from the estimate regardless of rate.
Thus as best I can see, if we're trying to make the best estimate
possible based on history, you should look at peaks, calculate the
Peukert capacity based on that vs current SOC, and deduct from the SOC
based on the actual, literal AH consumed. You could point out that the
peaks drawn in the past may not be consistent with the future needs,
this is the case with all estimates which use history to estimate
capacity in any way. It will only be accurate when history is
consistent with future needs.
Danny
Victor Tikhonov wrote:
Thanks Peter,
No matter how you slice it, gadget will never show how far you can
drive, one reading or ten readings. Best it will do is show
how much you've spend and how much remains *if* you keep spending
at the same rate which you generally may not. That's the source
of the problem.
It is not a problem to estimate range based on past (1 min, 10 miles,
whatever I choose) history. Problem is you're either forced to drive
the same way if you want believe the readout, or accept the fact that
it may be way off if you'll drive differently (which is not always
up to you).
Again I have only one 3 digit display for relative SOC (+ analog bar).
I don't really expect clear answer from anybody, there is simply
none exist. Will do my best.
Victor
--- End Message ---
--- Begin Message ---
I had a boat that I had financed and when I was ready to convert my Isuzu I
refinanced my boat and took out the extra cash I had belt up in equity
lowered my intrest rate and lowered my payments and got the cash to build my
EV.
Tom
----- Original Message -----
From: <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, April 26, 2007 12:53 PM
Subject: financing an EV
The way I financed mine. I purchased an already converted Chevy S10 from
the seller. Financed $5,000 of the purchase, check was written directly to
the seller by State Farm Loans.
I did have to prove that the 84 S10 was in fact worth $5,000 by indicating
it was an electric vehicle.
Now, State Farm only writes the check to the name of the vehicle seller.
You could sell the vehicle to a trustworthy friend, then get a loan to
purchase the vehicle from the friend for $5-10,000. and get your friend to
reimburse you the money?
It seems too easy that maybe it isn't possible.
The problem is that the state will rip you off for the taxes unless you
state you only purchased the car for $100.
Well, good luck this is all off topic other than getting you started in an
EV.
--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.5.463 / Virus Database: 269.6.1/777 - Release Date: 4/26/2007
3:23 PM
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--- Begin Message ---
NiMH cannot be put in parallel without a charge controller. They can't
be charged directly in parallel nor can they even be connected in
parallel after being charged.
Large series strings also come with serious balance issues. They're not
very tolerant of overcharge so it's a bad idea to bring all the cells up
to full by overcharging the cells which start with a higher SOC.
These two issues pretty make it difficult to use many small, cheap cells
as a NiMH pack. Well, Prius did but they had a great design and don't
use nearly as much capacity. IIRC there were some people trying to
build with "D" NiMH which is up to 9AH. There are other issues- the
cheap ones don't survive high discharges for long.
NiMH shouldn't be soldered, the button area has some kind of
heat-sensitive plastic underneath it. It's bad news for the batt. They
need to be connected with welded tabs.
Danny
[EMAIL PROTECTED] wrote:
Anyone every been crazy enough to build an EV pack out of AA sized cells? I
assume pack construction would drive you insane :-) Maybe the scooter/bike
guys then?
These guys seem to have some ridiculously cheap deals ($100 min order though I
think) on surplus small cells:
http://www.73.com/a/0658.shtml
Sanyo KR-1700E NiCad $0.23 ea, ~14k in stock
1700mAh 4/3A, discharge curves up to 8C, charge curves up to 1.5C
http://www.73.com/specs/th720.pdf
50 strings of 120 would yield 89Ah @ 144V, Imax ~680A, Rint ~17mOhm, 555 lbs
plus pack construction for $1380 plus materials. Only 12000 solder points ;-)
2x18650 LiIon cells in qualcomm packs (used) $0.89 ea, 13,500 in stock
1200mAh @7.2V
8x1.7Ah NiMh cells in HP laptop packs (new) $0.69 ea, 5600 in stock
1700mA @ 9.6V
1.2Ah Duracell/Toshiba NiMh AAs (new 95-97 vintage) $0.25 ea, 25k in stock
Anyone ever dealt with these guys? Does radio shack carry a 6000 AA carrier
sled? :-)
Rob
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http://www.lime.com/blog/savasthi/10941/the_fast__the_eco-friendliest
Chip Gribben
NEDRA Webmaster
http://www.nedra.com
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--- Begin Message ---
>>Careful - Graphic Content<<
<<Small Children should be removed from the room before opening>>
Just a crude graphic to illustrate the point.
I modified it to a version more appropriate for display on an EV.
Use that half and give the other to your gas driving buddies;
if you dare }:->
http://home.gci.net/~saintbernard/Universal_Sign_for_Gas.jpg
:-O
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--- Begin Message ---
Victor Tikhonov writes:
>
> Simple scenario: my wife wants to borrow the EV to go somewhere
> and asks if she can make it there - SOC shows 50% (as it was driven
> at 50A consumption last time before parked). Unless it's
> obviously short distance the answer is - no one knows. Depends
> how aggressively she will drive. How useful is that gauge??
>
> With 50% SOC displayed, she gets on freeway, reach 70 mph and
> suddenly it shows 12% and plunging down really fast. Nice...
Actually, this is pretty useful. She just needs to know that if
she sees this, she needs to back off to get more range.
It's kind of like driving an ICE with just one gallon of gas in
the tank. Is there enough for your trip? It depends on how you
drive and on the distance. Most people understand that when they
get low on gas that they need to drive gently to get the most range.
Ralph
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--- Begin Message ---
Hi Jeff,
The trans I chose for the first incarnation of my "EJ-7" Jeep is a 1971
Chevy Turbo 350. For controls, it's got 3 inputs. It's got a governer,
driven off of the output shaft. As I understand it, it is primarily used
for judging when to allow a downshift based on road speed to keep from
throwing a rod if you throw the lever into 1st at 90 MPH. I don't think the
function of that will change too much, although there are tuning kits for it
out there. There is a cable from the throttle to the valve body that
apparently makes some decisions based on throttle position only. I haven't
gotten to that chapter in the book yet, but I wonder if pinning it to the
full throttle position might go a long way toward keeping the RPM up where
we want to see it. And it's got a vacuum modulator. As I understand it so
far, the trans uses different line pressures in different gears, but does
not vary the main line pressure (the actual pump pressure) based on load.
It does however alter both the pressure applied to the clutches during a
shift, and the shift points, based on the vacuum present in the manifold,
which is handled by the vacuum modulator. This is the one that I'm thinking
might require some thought. With an ICE, you want both shift points and
shift firmness to go up with reduced manifold vacuum. We want shift points
to always be high, but shift firmness to vary with throttle position.
Divorcing the functions may be a challenge. I suspect this may be the source
of some of the problems people have had getting an automatic to act
correctly in the past. If you just left the vacuum off the modulator, I
suspect the shift points would be about right, but you'd get part throttle
shifts that were way too harsh. I need to figure out how to keep the shift
points high, yet have the shift firmness vary with throttle position. I may
mess with using vacuum from an electric vacuum pump used for the power
brakes to fake the modulator. If worse comes to worse, there are manual
shift valve bodies available for the Turbo 350, but I don't want to have to
teach the family how to know when to shift. The right way would be to have
the shift firmness vary linearly with torque production. We'll see if I can
get anywhere close.
The Turbo 350 came in two versions, one with no electronics, and one with a
lockup converter. Since I didn't want to waste battery energy spinning up
the heavy converter, I got one of the earlier ones with no lock up mechanism
(which also makes them cheap, I paid $80), and I'm planning on going
converterless. But personally, I was glad to see that there isn't a single
electrical connector on this trans. I'm sure wonderful things could be done
by controlling the trans with a computer, and I've got some programming
experience, but I'd rather deal with valves and springs. With the weather
and physical stresses this thing will see, I'd like to keep the fragile
electronics to a minimum. I've had enough trouble with radios and the nav
system in the other cars.
Marty
----- Original Message -----
From: "Jeff Shanab" <[EMAIL PROTECTED]>
To: "Electric Vehicle Discussion List" <ev@listproc.sjsu.edu>
Sent: Thursday, April 26, 2007 8:38 PM
Subject: Re: Motor, controller & battery recommendations?
Another thing about automatics. at lease the GM ones.
The pump pressure is varied to effect the firmness of the shift.
in pre-96 vehicles this was done off of engine vacuum. without the
engine vacuum to modulate the pressure it hammers on shifting. This is
not the vacuum used to shift in the even older transmissions, we are
talking about pump pressure.
After 96ish the ECM sends a PWM signal to the tranny to regulate the
pressure. It uses the TPS,Map sensor(expensive vacuum sensor), and speed
to determine the pressure needed. Drag racers with these newer trannies
use a little black box to supply the signal to allow firmer ,quicker
shifts with highly modded engines (see Summit racing)
Since you won't otherwise need the ECM, it may be a good idea to
make sure the auto tranny you have doesn't need some extra signals.
of course the cool part is that with a PIC micro you can
up-shift,downshift, adjust pump pressure and select torque converter
lock/unlock.
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--- Begin Message ---
Apologies if someone has already mentioned this, I haven't read the rest
of the thread;
The newer versions of the Lynch motor have a higher power
http://www.agnimotors.com/
http://www.agnimotors.com/home/index.php?option=com_content&task=view&id=5&Itemid=36
Peter VanDerWal wrote:
I disagree.
The Lemco/Lynch motors are nice, but not powerfull enough for this
application. At least not a single motor.
The continuous power is only about 6hp, which is probably not enough to
maintain 60-70 mph on a vehicle with no doors (i.e. poor aerodynamics),
even with doors it would be questionable.
Secondly, the ammount of time it can produce the max power (16hp?) is
measured in seconds.
Try climbing a long hill at any speed and poof goes the motor. With
single speed ratio's the amount of current needed for hills is virtually
the same at 5mph as it is at 30 mph, so tying to climb slower doesn't
help.
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--- Begin Message ---
Watts = Amps X Volts.
400W divided by 12 Volts = 33.33333 Amps
130 Amps X 12 Volts (Guessing) = 1560 Watts
David C. Wilker Jr.
USAF (RET)
----- Original Message -----
From: "Jack Riggi" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, April 26, 2007 5:01 PM
Subject: Re: [EV] RE: Issues involved in a controller bypass? (ForkenSwift)
I would like to thank the people for helping me with how things work , you
really helped clear things up on how it works . Sorry I did not answer
sooner but I just got a job out of town & did not have internet connecton
were I was , got firerd today now have more time but no money to convert my
truck to ele. Does any body know how many amps 400watts 12v are, & how many
watts there are in 130 amps . am working on a new project with wind power
to help recharge batts. I am sure one of you will know . Thanks again Jack
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Saturday, April 21, 2007 10:57 PM
Subject: Re: [EV] RE: Issues involved in a controller bypass?
(ForkenSwift)
Jack Riggi wrote:
I am really new on this ele. thing but what are you talking about? what
are you trying to do? I don't even know what a controller or a bypass
is?
Hi Jack,
It's not too hard to understand. In an electric car, you have a motor,
batteries, and a controller. The controller is like a big light dimmer;
it controls your speed. Without it, your "gas pedal" would just be an
on-off switch (full speed or nothing)!
The controller is usually your weakest link; it limits how fast you can
go and how fast you can accelerate. This is due to cost. A wimpy
controller is around $500; a good one $1000, and a really fast on $2500.
With a simple DC motor, you can get "maximum power" by just bypassing the
controller -- i.e. switching the motor *directly* to the batteries with
no controller at all. You get tire-spinning (axle breaking, battery
bursting, motor murdering) performance without an expensive high-power
controller. So there is a strong interest in just using a big switch to
avoid having to buy an expensive high-power controller.
So, most of these discussions are about finding ways to add a bypass
switch without breaking something in the process.
--
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
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--- Begin Message ---
I would agree as well. Your ICE gas gauge doesn't tell you how far
you can go, just what's left in the tank. It seems like trip
computers that try to estimate DTE based on previous driving
conditions have the same trouble, and bounce around depending on how
you are driving. Seems like best you can do is a rolling average
with an adjustable averaging window. If there was a way to just more
directly estimate remaining Ah's it seems like thats what you really
want to know.
SO, how about this :-) Has anyone ever tried monitoring electrolyte
pH in real time? I would assume that as it progresses from acid ->
water from full charge to empty that the pH would track this fairly
quickly & smoothly? Seems like how much energy you have left should
be a direct function of how many ions you have left in the
electrolyte. There are plenty of pH meters out there, but I have no
idea if there is any sort of cheap bulk sensor that you could deploy
across the pack in an economical way so as to have an average picture
of pack state of charge. Would be really cool if you could monitor
each cell independently in real time :-)
Rob
On Apr 26, 2007, at 9:55 PM, Ralph Merwin wrote:
Actually, this is pretty useful. She just needs to know that if
she sees this, she needs to back off to get more range.
It's kind of like driving an ICE with just one gallon of gas in
the tank. Is there enough for your trip? It depends on how you
drive and on the distance. Most people understand that when they
get low on gas that they need to drive gently to get the most range.
Ralph
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--- Begin Message ---
Similar problems with NiCad's, or no?
On Apr 26, 2007, at 7:09 PM, Danny Miller wrote:
NiMH cannot be put in parallel without a charge controller. They
can't be charged directly in parallel nor can they even be
connected in parallel after being charged.
Large series strings also come with serious balance issues.
They're not very tolerant of overcharge so it's a bad idea to bring
all the cells up to full by overcharging the cells which start with
a higher SOC.
These two issues pretty make it difficult to use many small, cheap
cells as a NiMH pack. Well, Prius did but they had a great design
and don't use nearly as much capacity. IIRC there were some people
trying to build with "D" NiMH which is up to 9AH. There are other
issues- the cheap ones don't survive high discharges for long.
NiMH shouldn't be soldered, the button area has some kind of heat-
sensitive plastic underneath it. It's bad news for the batt. They
need to be connected with welded tabs.
Danny
[EMAIL PROTECTED] wrote:
Anyone every been crazy enough to build an EV pack out of AA sized
cells? I assume pack construction would drive you insane :-)
Maybe the scooter/bike guys then?
These guys seem to have some ridiculously cheap deals ($100 min
order though I think) on surplus small cells:
http://www.73.com/a/0658.shtml
Sanyo KR-1700E NiCad $0.23 ea, ~14k in stock
1700mAh 4/3A, discharge curves up to 8C, charge curves up to 1.5C
http://www.73.com/specs/th720.pdf
50 strings of 120 would yield 89Ah @ 144V, Imax ~680A, Rint
~17mOhm, 555 lbs plus pack construction for $1380 plus materials.
Only 12000 solder points ;-)
2x18650 LiIon cells in qualcomm packs (used) $0.89 ea, 13,500 in
stock
1200mAh @7.2V
8x1.7Ah NiMh cells in HP laptop packs (new) $0.69 ea, 5600 in stock
1700mA @ 9.6V
1.2Ah Duracell/Toshiba NiMh AAs (new 95-97 vintage) $0.25 ea, 25k
in stock
Anyone ever dealt with these guys? Does radio shack carry a 6000
AA carrier sled? :-)
Rob
Amy Smith
[EMAIL PROTECTED]
Birth Doula
Childbirth Educator
602-277-1572
602-405-3744
"Education is not the filling of a pail, but the lighting of a fire" -
Yeats
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