EV Digest 2672
Topics covered in this issue include:
1) Re: AC controllers
by "Mark Thomasson" <[EMAIL PROTECTED]>
2) Proposed Welcome message update
by Bruce EVangel Parmenter <[EMAIL PROTECTED]>
3) Re: Motor, surprise!
by Peter VanDerWal <[EMAIL PROTECTED]>
4) Re: more therapy and adaptor questions
by Chris Weaver <[EMAIL PROTECTED]>
5) ev
by "garry" <[EMAIL PROTECTED]>
6) GM stops inductive retrofits
by Bruce EVangel Parmenter <[EMAIL PROTECTED]>
7) Re: AC controllers
by Peter VanDerWal <[EMAIL PROTECTED]>
8) Re: AC controllers
by Peter VanDerWal <[EMAIL PROTECTED]>
9) Re: Sob... I think if fried my motor.
by Jim Coate <[EMAIL PROTECTED]>
10) Re: AC controllers
by "1sclunn" <[EMAIL PROTECTED]>
11) Re: Better range from less weight
by Jim Coate <[EMAIL PROTECTED]>
12) Don't tap the battery pack (was: Today's mystery question with
electricity)
by "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
13) Re: Sob... I think if fried my motor.
by "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
14) Re: AC controllers
by Lee Hart <[EMAIL PROTECTED]>
15) RE: Better range from less weight - don't forget batteries
by "Mark Fowler" <[EMAIL PROTECTED]>
16) Re: Better range from less weight
by John Wayland <[EMAIL PROTECTED]>
17) Re: Don't tap the battery pack (was: Today's mystery question
withelectricity)
by John Wayland <[EMAIL PROTECTED]>
18) Re: Evercells versus Yellow tops
by John Wayland <[EMAIL PROTECTED]>
19) Re: ZAP RAP FEVER: page to sell or trade your EV
by "1sclunn" <[EMAIL PROTECTED]>
--- Begin Message ---
I invite everyone to comment on the following idea for a low tech method of
controlling motor voltage, and thus vehicle speed. Instead of leaving the
batteries in a monolithic lump and controlling motor voltage with a
sophisticated electronic device, lets use the fact that the battery bank is
composed of smaller units that may be rearranged with contactors to get
various voltages. For example, with seven batteries in the bank, it is
possible to rearrange them to get seven voltage steps, from zero volts to
the voltage of all the batteries in series. With 15 batteries, 15 steps are
possible. The trick is to rearrange the batteries without using an
unreasonable number of contactors. See
http://www.geocities.com/thomassonmj/electric_drive.html for a diagram of
how this may be done. http://www.austinev.org/evalbum/439.html shows the
test platform. I started small with a minibike and only 3 voltage steps
(using three 12 volt batteries) in the control system. The three relays and
a multiposition switch comprising the control system cost less than $20.
Electro-mechanical relays are much easier to trouble shoot and repair that
electronic FET's and integrated circuits, and more efficient. Solid state
relays could also be used. Regenerative braking occurs automatically as you
back off the throttle, or not at all if the throttle goes immediately to
zero.
Criticize freely... I can take it!
Thanks for your feedback.
Mark Thomasson
----- Original Message -----
From: "1sclunn" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Saturday, March 22, 2003 6:59 PM
Subject: Re: AC controllers
> Hi Mark
...................
>
> Tell us of your project? what do you want it to do?
>
....................
--- End Message ---
--- Begin Message ---
I looked at the Welcome message that is sent out upon a
new subscription
http://geocities.com/ev_list/evlistwelcomeold.txt
(^this is the current old version ^)
It is from a long time ago and much has changed. To bring
the Welcome message up to the year 2000, I propose
http://geocities.com/ev_list/evlistwelcomeproposed.txt
(^this is the new version I am proposing^)
I request that people send me feedback to hone and
adjust this proposed update to the Welcome message before
asking that it be used for new EV List subscribers.
Please let me know.
=====
' ____
~/__|o\__
'@----- @'---(=
. http://geocities.com/brucedp/
. EV List Editor & RE newswires
. (originator of the above ASCII art)
=====
__________________________________________________
Do you Yahoo!?
Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop!
http://platinum.yahoo.com
--- End Message ---
--- Begin Message ---
Ok I admit it. I'm a nobody, just a guy that reads a lot and has done a
few experiments. So when I tell Garry that Back EMF is not a loss and
he doesn't believe me, well it's annoying but not surprising.
But Rich Rudman makes a living building motor controllers (among other
things) so you'd expect him to know a thing or two about motors.
He tells Garry "Back EMF is clearly not a loss."
But Garryu doesn't believe him either. That's a bit surprising.
Then Lee Hart weighs in. Now Lee is a subject matter expert on motors
and electricity. I doubt you could find 200 people in the entire world
that know more about motors than Lee does.
Lee says:
"It is saying that for the device to work as
a useful motor, there HAS to be back emf. Perfect efficiency (PowerOut =
PowerIn) requires the back emf to EQUAL the applied voltage. "
Clearly then Back EMF is not a loss, in fact it is a desirable feature.
But Garry won't believe Lee either...astounding!!
You know I think God himself could materialize as a burning bush in
front of Garry, hand him a stone tablet engraved with "Back EMF is not a
loss" and Garry wouldn't believe him either.
Rich, don't bother with the 2x4, you could drop a planet on this guy and
it wouldn't make a difference.
--- End Message ---
--- Begin Message ---
Hi Steve,
Thanks for the encouragement. I need about 50 miles round trip (in case I
can't arrange for charging at work). I really need 30, but I need it over
the life of the pack, so I want some design margin. Most of the commute is
on the highway. Since I work late a lot, one leg of this is often at 65+
mph. Anything much less than that will end up pushed into a ditch by an
impatient SUV driver. Also, we have some fair hills here going up and down
the mesas along the coast, and where I work and where I live are both on
top of a mesa, so the last part of the drive will always be uphill.
At this point I'm leaning towards making sure I the motor/controller give
me the performance I want, even if I need to skimp on my first set of
batteries. Hopefully there will be better performing battery options to
chose from next time.
As you interpreted correctly, I meant the pilot bearing is on the end of
the crankshaft, not the driveshaft. One idea I had was to take a
crankshaft and cut the end off. Then I just need to drill (read have
someone with real tools mill out) the center out for the motor shaft,
instead of trying to get the seat right for the pilot bearing. Its ironic
that I have a spare crankshaft in the garage (in the removed ICE), but it
seems like a waste to wreck the ICE just for that, although I've called
around and none of the parts yards are interested in the ICE. Think I'll
call around to see how cheap I could get the crankshaft before I go very
far with that idea.
I have a digital cammera and I'm taking pictures, which I hope to post at
some point. I've never been a fan of camcorders. Since I don't have kids,
I haven't been required to get one in order to keep the grandparents happy :)
I'll keep the list posted on what I end up doing with the adaptor.
Thanks,
Chris
At 11:03 AM 3/23/2003 -0800, 1sclunn wrote:
Thanks for update on your project. With all the talk about bats ,controllers
, chargers ,the adaptor plates seem left behind. I wrote a while back about
me EV friend Tom who knew a retired machinists and I had him make the hub
for the Toyota torcell that I'm doing with Tom ( we are moving sloooow with
this project ) It looked good and I had him do the hub for Russ W up grade
(the slow 72v )and one for his friends car (another sloooow project that has
been sitting in my yard for almost a year) . Last week when I went for my
weekly visit (and we blew up another one of tom's home made chargers) I
heard the bad news. His friend the machinest had passed away. If Victor
gets the adaptor hub and plate problem covered I think this will be a big
plus for his ac drive . There was talk of a hub that could be used for many
different cars but haven't herd much lately. I will be very interested in
what you do as for me making the hub and adaptor plate is about 30% of the
conversion. I'm not real happy with the hubs I make on my raggedy old lathe
and it takes about a day to do just the hub(for me) . Have you though about
Videoing your conversion.? I would put it on my EVTV program if you did.
The hub will need to hold that polite bearing just like the gas motor did so
that your electric engine can hold the tranny shaft in the same place ( Just
a little joke for Hump who should be starting his project soon) .
Did you write about what you want the truck to do (performance) . ?
I like your enthusiasm hope it's spreads.
Steve Clunn
----- Original Message -----
From: "Chris Weaver" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Saturday, March 22, 2003 9:22 PM
Subject: more therapy and adaptor questions
> Today a friend an I pulled out the engine and transmission out of my 99
> Toyota Tacoma extended cab donor truck ( I guess I can call it a glider
now
> :) ). What a great feeling!!
>
> I should say that this hasn't been without a few glitches. I waited to
> start ripping out stuff until I had received a signed title from the
> leasing company from which the guy that I bought it from was leasing
> it. Then I started gutting it. I had called the DMV info line and asked
> what was necessary to register a vehicle for non-operation. Should be no
> problem. Finally I got around to actually going to the DMV (California
> Dept. of Motor Vehicles) and doing the paperwork and paying my $880 in
> taxes (ouch). The the guy from the DMV told me "You'll have to get a
smog
> test before we can give you a clean title". Oh Shxt. I've already pulled
> out the gas tank, radiator, emmisions, ++. Fortunately I must have won
the
> lottery with DMV people, since when I explained that I was already ripping
> stuff out and working on converting it to electric, he just said "I've
> never had anybody that was doing that before" and then proceeded to tell
my
> how to do a deferred registration. It could have been real ugly, but I
was
> very fortunate. He could have required me to deliver a smog cert. and I'd
> have been putting it all back together. There were people at the DMV
> office that were there for the 4th time for stuff a lot less
> out-of-the-ordinary stuff than I had. I still have to deal with the
> emissions "referee" but I think that will be a case of proving the obvious
> fact that I no longer need to participate in the smog program, since I
> don't have an engine any more.
>
> Now I have several questions. When I pulled apart my bell housing+tranny,
> I found that my flywheel has in the center (actually as part of the flange
> that is part of the driveshaft) a pilot bearing that centers and supports
> the shaft from the transmission. Do I need to make that part of my
> coupling/adaptor plate? One of the motors I'm looking at is Victor's
5133,
> which has a outside-splined shaft. He offers an adaptor to convert that
> spline to a grooved-shaft. Do I need this? Even for any other type of
> motor, seems like if I can come up with a coupling that converts a splined
> shaft or whatever the motor has to the 10-bolt flange that the flywheel
> attaches to, and would hold a pilot bearing, then I'm good to go. But I
> haven't seen much in the reading I've done that mentions the pilot bearing
> or different shaft types.
>
> Any insight to what I should do here is greatly appreciated.
> Thanks,
> Chris
>
>
--- End Message ---
--- Begin Message ---
Hi people,
I'm on a bit of a buzz today and I just thought I would share it with you.
This will seem unimportant to some but for someone who has never played golf
ones first ride in a golf cart can be quite exciting, especially if you are
somewhat keen on building an EV.
I went out to look at a cart that is for sale locally, I figure its already
an EV so maybe it would make my simple project easier.
The cart I was to look at was stored behind 3 other carts and someone had to
move them to get it out and take it for a test ride :)
I think I have enough ev bits now to make one but its almost irresistible to
grab this and add it to the pile, a nice 300 amp controller 6 Trojan t105's
a fuel gauge and charger and it doesn't need building you just jump on and
take it for a joy ride :)
Shame they wont let us use them on the roads here ... I have a will so there
is bound to be a way :)
I'm hooked :)
Garry Stanley
Cable.net.nz
--- End Message ---
--- Begin Message ---
On the http://ev1-club.power.net/ page there are two
scanned images of the letter from GM.
http://ev1-club.power.net/archive/020315/gmatv1.gif
http://ev1-club.power.net/archive/020315/gmatv2.gif
GM basically saying 'We don't have to now that we have won'
The RAV4 EV drivers will have to secure their source for
small paddle chargers and find the funding if they want
to retrofit any large paddle chargers or do any new
installations.
=====
' ____
~/__|o\__
'@----- @'---(=
. http://geocities.com/brucedp/
. EV List Editor & RE newswires
. (originator of the above ASCII art)
=====
__________________________________________________
Do you Yahoo!?
Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop!
http://platinum.yahoo.com
--- End Message ---
--- Begin Message ---
Been their done that. This idea dates back over 100 years and used to
be how all EVs operate.
The problem is you end up with discreet voltage steps instead of the
smooth variability of a modern PWM controller. Add in the fact that
high current contactors are very expensive (more expensive for the set
than a PWM controller) and it's easy to see why almost nobody builds EVs
that way anymore.
FWIW they were still using this method in the '70s for golf carts and
City/Commuta cars.
It works fine on low power setups though.
PS Contactor REGEN only works with PM motors and shunt/sep ex motors.
Doesn't work worth beans with series wound motors. But then REGEN with
series wound motors is tough to do any way.
On Sun, 2003-03-23 at 20:57, Mark Thomasson wrote:
> I invite everyone to comment on the following idea for a low tech method of
> controlling motor voltage, and thus vehicle speed. Instead of leaving the
> batteries in a monolithic lump and controlling motor voltage with a
> sophisticated electronic device, lets use the fact that the battery bank is
> composed of smaller units that may be rearranged with contactors to get
> various voltages. For example, with seven batteries in the bank, it is
> possible to rearrange them to get seven voltage steps, from zero volts to
> the voltage of all the batteries in series. With 15 batteries, 15 steps are
> possible. The trick is to rearrange the batteries without using an
> unreasonable number of contactors. See
> http://www.geocities.com/thomassonmj/electric_drive.html for a diagram of
> how this may be done. http://www.austinev.org/evalbum/439.html shows the
> test platform. I started small with a minibike and only 3 voltage steps
> (using three 12 volt batteries) in the control system. The three relays and
> a multiposition switch comprising the control system cost less than $20.
> Electro-mechanical relays are much easier to trouble shoot and repair that
> electronic FET's and integrated circuits, and more efficient. Solid state
> relays could also be used. Regenerative braking occurs automatically as you
> back off the throttle, or not at all if the throttle goes immediately to
> zero.
>
> Criticize freely... I can take it!
>
> Thanks for your feedback.
>
> Mark Thomasson
>
>
> ----- Original Message -----
> From: "1sclunn" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: Saturday, March 22, 2003 6:59 PM
> Subject: Re: AC controllers
>
>
> > Hi Mark
> ...................
> >
> > Tell us of your project? what do you want it to do?
> >
> ....................
>
--
EVDL
--- End Message ---
--- Begin Message ---
Oops, forgot to mention.
Contactor controllers normally rearrange the pack into series/parallel
setups.
IE. a 48V pack of 4 12V batteries will be arranged as all four in
parallel for 12V, two sets of two for 24V and all together for 48V. Plus
usually a starting resistor in series with the 12V setup. This gives
four steps, plus stop.
Tapping the pack at individual batteries like you suggest means that
none of the batteries will be discharged to the same level. The first
battery gets used all of the time and the one at the other end of the
string hardly ever gets used.
This causes the pack to become unbalanced(a bad thing). Your range will
be limited by the first battery which will run out fairly quickly, while
1/2 the batteries are hardly discharged at all.
Range from this setup will be about 1/4 the range of using all the
batteries as one pack with a PWM controller or a series/parallel
contactor controller.
> > various voltages. For example, with seven batteries in the bank, it is
> > possible to rearrange them to get seven voltage steps, from zero volts to
> > the voltage of all the batteries in series. With 15 batteries, 15 steps are
> > possible. The trick is to rearrange the batteries without using an
> > unreasonable number of contactors. See
> > http://www.geocities.com/thomassonmj/electric_drive.html for a diagram of
> > how this may be done. http://www.austinev.org/evalbum/439.html shows the
> > test platform. I started small with a minibike and only 3 voltage steps
> > (using three 12 volt batteries) in the control system. The three relays and
> > a multiposition switch comprising the control system cost less than $20.
> > Electro-mechanical relays are much easier to trouble shoot and repair that
> > electronic FET's and integrated circuits, and more efficient. Solid state
> > relays could also be used. Regenerative braking occurs automatically as you
> > back off the throttle, or not at all if the throttle goes immediately to
> > zero.
> >
> > Criticize freely... I can take it!
> >
> > Thanks for your feedback.
> >
> > Mark Thomasson
> >
> >
> > ----- Original Message -----
> > From: "1sclunn" <[EMAIL PROTECTED]>
> > To: <[EMAIL PROTECTED]>
> > Sent: Saturday, March 22, 2003 6:59 PM
> > Subject: Re: AC controllers
> >
> >
> > > Hi Mark
> > ...................
> > >
> > > Tell us of your project? what do you want it to do?
> > >
> > ....................
> >
> --
> EVDL
>
--
EVDL
--- End Message ---
--- Begin Message ---
If you could squeeze it in, a used DCP Raptor 1200 or one of Otmar's new
Zilla-1000's would be rather nice. Even with say 400 amp limit on the
batteries, could get 800+ motor amps on start up for the brief instant
to get moving up a hill, and still have some headroom so not torturing
the controller each time.
Lawrence Rhodes wrote:
By revving the motor and popping the clutch I probably caused a a big spike
and fried the controller. I was stalling the motor so I turned into a
driveway but the damage was already done and it died right there. I backed
down the hill and coasted home. It blew the KSI fuse. I replaced it but
the car is still dead. Looks like I need another controller or a rebuild
that would go to 500 amps. http://www.austinev.org/evalbum/418.html
Here is my car. Any of you Gurus like to comment on this 120v system and
give some advice please on making it a more reliable vehicle in the go
faster and last longer department. It has two strings now. I wouldn't mind
having one string and going higher on voltage. As the batteries die ( Which
Delphi seem to do. I could just take out the bad ones and lower the voltage
slightly. It would however take a better controller. Also someone
mentioned using a contactor to get full pack voltage for the hills.
_________
Jim Coate
1992 Chevy S10
1970's Elec-Trak
http://www.eeevee.com
--- End Message ---
--- Begin Message ---
Sounds like money my be a problem here. The PWM also converts batterie
volts into motor amps this is very nice. When I blow my first Curtis which I
got from solar car I drove around with the pack set up as two strings of 60v
, no steps just on and off( say the controller will be hear any day , over
and over ) . I truned the key on and slipped the clutch and used the gears
to adjust the speed. I was very supprized at the distance I losted or how
much more ah I used to make the same trips.
there is also the problem of charging the batteries. Is money the reason
your concidering this>?
----- Original Message -----
From: "Peter VanDerWal" <[EMAIL PROTECTED]>
To: "EV" <[EMAIL PROTECTED]>
Sent: Sunday, March 23, 2003 9:18 PM
Subject: Re: AC controllers
> Been their done that. This idea dates back over 100 years and used to
> be how all EVs operate.
> The problem is you end up with discreet voltage steps instead of the
> smooth variability of a modern PWM controller. Add in the fact that
> high current contactors are very expensive (more expensive for the set
> than a PWM controller) and it's easy to see why almost nobody builds EVs
> that way anymore.
>
> FWIW they were still using this method in the '70s for golf carts and
> City/Commuta cars.
>
> It works fine on low power setups though.
>
> PS Contactor REGEN only works with PM motors and shunt/sep ex motors.
> Doesn't work worth beans with series wound motors. But then REGEN with
> series wound motors is tough to do any way.
>
> On Sun, 2003-03-23 at 20:57, Mark Thomasson wrote:
> > I invite everyone to comment on the following idea for a low tech method
of
> > controlling motor voltage, and thus vehicle speed. Instead of leaving
the
> > batteries in a monolithic lump and controlling motor voltage with a
> > sophisticated electronic device, lets use the fact that the battery bank
is
> > composed of smaller units that may be rearranged with contactors to get
> > various voltages. For example, with seven batteries in the bank, it is
> > possible to rearrange them to get seven voltage steps, from zero volts
to
> > the voltage of all the batteries in series. With 15 batteries, 15 steps
are
> > possible. The trick is to rearrange the batteries without using an
> > unreasonable number of contactors. See
> > http://www.geocities.com/thomassonmj/electric_drive.html for a diagram
of
> > how this may be done. http://www.austinev.org/evalbum/439.html shows
the
> > test platform. I started small with a minibike and only 3 voltage steps
> > (using three 12 volt batteries) in the control system. The three relays
and
> > a multiposition switch comprising the control system cost less than $20.
> > Electro-mechanical relays are much easier to trouble shoot and repair
that
> > electronic FET's and integrated circuits, and more efficient. Solid
state
> > relays could also be used. Regenerative braking occurs automatically as
you
> > back off the throttle, or not at all if the throttle goes immediately to
> > zero.
> >
> > Criticize freely... I can take it!
> >
> > Thanks for your feedback.
> >
> > Mark Thomasson
> >
> >
> > ----- Original Message -----
> > From: "1sclunn" <[EMAIL PROTECTED]>
> > To: <[EMAIL PROTECTED]>
> > Sent: Saturday, March 22, 2003 6:59 PM
> > Subject: Re: AC controllers
> >
> >
> > > Hi Mark
> > ...................
> > >
> > > Tell us of your project? what do you want it to do?
> > >
> > ....................
> >
> --
> EVDL
>
>
--- End Message ---
--- Begin Message ---
Lee Hart wrote:
Around here, a popular high school stunt is to take the body off some
old rused out pickup truck, and crudely graft on some car body that has
about the right wheelbase. The car body normally sits absurdly high on
the frame, but this allows them to use ridiculously oversized tires.
This just begs for a picture to explain what the cars look like in the
end... is there a slang name for what they call these creations? (so I
can Google my way to a kid who put his creation on a web page)
_________
Jim Coate
1992 Chevy S10
1970's Elec-Trak
http://www.eeevee.com
--- End Message ---
--- Begin Message ---
At 06:48 PM 3/22/03, you wrote:
I have all of my 12V electronics - blinkers, headlights etc. hardwired to
one of my batteries in my 36V 1960 electric shopper. From the hardwire, it
goes through a fuse box, with a 15amp fuse on each seperate accessory.
Everything works just fine aside from the stereo.
Tapping the pack is a BAD practice. Don't do this.
I have some 200 watt DC-DC converters (somewhere) that will run on
36 volts. (Actually, I sold some of these to Rod Wilde. He might have a few
left.) Use one or more of these instead of tapping the pack.
I repeat: Tapping the pack is BAD practice. It is really tough on
your batteries. One battery will not get enough charge and the others will
be massively overcharged.
_ /| Bill "Wisenheimer" Dube'
\'o.O' <[EMAIL PROTECTED]>
=(___)=
U
Check out the bike -> http://www.KillaCycle.com
--- End Message ---
--- Begin Message ---
At 06:17 PM 3/22/03, you wrote:
I was think about this today . if you reved the motor and sliped the clutch
would you have more torque that just taking off from o rpm ( I know this
would keep the controller happy) .
No. Not the way to do it. The motor has max torque at stall.
as the rpm climes I know there is less
torque . What I am wondering is if this type of motor reveing clutch
slipping makes any more toqure that what the motor is making to begin with.
Not counting the weight of the flywheel ect. I know it will make some heat.
Slipping the clutch won't help.
It's OK to very briefly stall the motor, but you can't do it long
at high amps. At high amps, you wouldn't want to hold the motor stalled for
more than a fraction of a second.
_ /| Bill "Wisenheimer" Dube'
\'o.O' <[EMAIL PROTECTED]>
=(___)=
U
Check out the bike -> http://www.KillaCycle.com
--- End Message ---
--- Begin Message ---
Mark Thomasson wrote:
> I invite everyone to comment on the following idea for a low tech
> method of controlling motor voltage, and thus vehicle speed...
> use the fact that the battery bank is composed of smaller units
> that may be rearranged with contactors to get various voltages...
> The trick is to rearrange the batteries without an unreasonable
> number of contactors. See
>
> http://www.geocities.com/thomassonmj/electric_drive.html
> for a diagram of how this may be done.
The first problem is that you are not loading the batteries equally.
Thus, they will discharge at different rates. I suppose you could rig
your control system to monitor individual batteries, and only allow
steps to be selected when that battery has enough charge. But that would
be rather unpleasant for the driver (can drive at 20 mph or 40 mph, but
not 30 mph because the battey for that step is dead).
Having the batteries discharge unequally also complicates things when
charging.
Next problem; you still have a lot of contactors. The way they are
arranged, if one fails shorted, it could be disastrous to close the next
one. You would need a lot of fuses, and/or "smart" control logic to
detect a stuck switch and so not close the next one.
This problem has been studied for a very long time by some great minds.
You might want to look at some of their solutions.
For example, the batteries can be switch in series-parallel combinations
so the load is always divided equally between them. If you had 12 6v
batteries, for example, they can be wired:
6v - all in parallel
12v - 6 strings of 2
18v - 4 strings of 3
24v - 3 strings of 4
36v - 2 strings of 6
72v - all in series
The classic series-parallel switch is a single contactor with 3
contacts:
______________________
+ __|__ K1b |
battery 1 ___ normally closed / K1c
|__________/___________| normally open
| K1a __|__+
/ normally open ___ battery 2
|______________________| -
If you don't need to do regen (carry current in both directions), then
K1a and K1c can be replaced by a big diode. Then series-parallel
switching is done with a single SPST contactor.
--
Lee A. Hart Ring the bells that still can ring
814 8th Ave. N. Forget your perfect offering
Sartell, MN 56377 USA There is a crack in everything
leeahart_at_earthlink.net That's how the light gets in - Leonard Cohen
--- End Message ---
--- Begin Message ---
If you are thinking of spending serious amounts of money then don't forget about other
battery chemistries.
Li-Ions will give you four times the watt-hours for the same weight.
In a few months time there will be some Li-Ion powered cars owned by ev-listers
lapping around.
The owners will be able to give some real world info on how carefully you need to
charge and discharge them so that they don't reach critical mass and explode in a
thermonuclear reaction that takes half the planet with it.
(OK, a bit of an overstatement, but you wouldn't think so based on some comments on
the list :-)
Mark
-----Original Message-----
From: Dave Davidson [mailto:[EMAIL PROTECTED]
Sent: Monday, 24 March 2003 3:08 AM
To: [EMAIL PROTECTED]
Subject: Re: Better range from less weight
I think a lot of this will depend on what you start out with. A good place
to start would be to look at the kit car market. For example, compare VW
bug based kits to a stock bug weight. Aerodynamics can improve quite a bit,
though, over some cars. However, a stock aerodynamic car will show less
improvement. I believe some Karmen Ghia conversions have already acheived
what you suggest.
However,in doing this, you have two different effects. Weight is a big
penalty in stop and go driving, what EVs are often used for. If you keep a
steady speed, weight is less of a factor. Conversely, aerodynamics is a big
factor in highway driving, but not much in stop and go type driving (low
speed).
One thought I had - and might do if I were 30 years younger - is to buy an
aerodynamic kit body, possibly one that someone started and lost interest in
(i.e. cheap). Then take a small pickup/blazer type vehicle with a similar
wheelbase and track, strip it down to just the frame and suspension, adapt
the kit body to it and build it up as an EV. You could probably easily get
a 50% battery weight or better without exceeding the GVW of the
chassis/suspension of the original truck.
As far as designing a body for the chassis, and making it as aerodynamic as
possible, that is beyond my abilities. However, I believe some on the list
could easily build up a fiberglass body, using similar techniques used for
boats. The hardest part, then, will be the design, mockup, wind tunnel
testing, etc (or take a casting of an EV-1 for the easy way out).
As for whether a project of this type is worth it, only you can answer that.
I believe it would have to be a labor of love, as I doubt it would ever
pay off financially. If you decide to experiment, you might want to try to
get a kit manufacturer interested in running a batch of bodies for a
particular vehicle, for example a SWB S-10 pickup donor. Include battery
boxes, etc. It could make for a very nice kit, but the market of people who
want to do that much work is fairly limited. Maybe sell a rolling chassis
with motor, controller, etc already installed, and a body ready to bolt on.
Just enough of a kit to avoid crash certification. Still a limited market,
though.
Just my thoughts...
Dave Davidson
Laurel, Maryland
1993 Dodge TEVan
>From: Bruce EVangel Parmenter <[EMAIL PROTECTED]>
>Reply-To: [EMAIL PROTECTED]
>To: [EMAIL PROTECTED]
>Subject: Better range from less weight
>Date: Sun, 23 Mar 2003 07:24:48 -0800 (PST)
>
>Pick-your-brains POST
>
>Range on lead-acid wet cell conversions is generally 50
>miles (at 65mph), unless you improve the battery to
>vehicle weight ratio (cut out the Detroit metal).
>
>How much weight can one strip from a conversion project?
>
>If the heavy metal body was lifted from the chassis
>and a fiberglass body made, how much weight could be
>saved and how much range could be added?
>
>How hard it is to make a fiberglass body? Is there
>a url showing how to do it?
>
>How would one design a better aerodynamic fibergalss
>body. Wind pusher trucks, SUVs, and vans lose range to
>wind resistance.
>
>If a person took an existing conversion and lighted
>the vehicle, could they reach the 70 mile range
>(at 65mph) mark?
>
>Is this too much work, or a project of deminising
>returns?
>
>
>
>=====
>' ____
>~/__|o\__
>'@----- @'---(=
>. http://geocities.com/brucedp/
>. EV List Editor & RE newswires
>. (originator of the above ASCII art)
>=====
>
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--- Begin Message ---
Hello to All,
Thought I'd weigh in on this.....
> Bruce EVangel Parmenter wrote:
> > How much weight can one strip from a conversion project?
Instead of stripping weight from a conversion project, you could pick a donor that is
already super light...read that Honda Insight (1847 lbs. without AC) or, if you can
even
find one in clean shape, a good 'ol '72 Datsun 1200 sedan (1587 lbs.). Both of these
can
hold quite a bit of battery weight, if suspension mods are done. Better still though,
use
something besides lead acid batteries, since that is now an option.
>
> > If a person took an existing conversion and lightened the vehicle,
> > could they reach the 70 mile range (at 65mph) mark?
>From Lee Hart:
> Since there are conversion EVs that have done it, of course it is
> possible. The "Red Beastie" designed by John Wayland comes to mind. The
> key is basically to get at least 50% of the total weight in batteries.
Yes, using lead acid batteries, that 50% mark is the target. Red Beastie had approx.
2500
lbs. of lead on board and weighed approx. 5300 lbs. for a 47% battery weight, and it
could
do 120 miles on an 80 degree day at 60-65 mph. Yes, that 120 miles resulted in a 100%
discharge, but 70 miles was a piece of cake. However....consider that the same vehicle
with just 850-900 lbs. of nickel zinc batteries could also do 120 mile per
charge...and,
with this smaller sized pack tucked away between the frame rails, the bed would be
fully
usable again! The truck would also be 1600-1700 lbs. lighter, so acceleration, passing
power, hill climbing ability, and fun factor would be dramatically increased.
> > Is this too much work, or a project of diminishing returns?
I think that any money spent on dramatic fiberglass mods, besides ending up looking
awful,
would be wasted in light of the same dollars spent on nickel zinc batteries over a lead
acid pack.
Just my two cents worth.....
See Ya....John Wayland
Current project...'66 Datsun minitruck with Zilla 1K HV, four ADC motors, sound system
with V8 subwoofer and 800+ watts, and a planned 216V Nickel Zinc pack for 90-100 mile
range.
--- End Message ---
--- Begin Message ---
Hello to All,
"[EMAIL PROTECTED]" wrote:
> At 06:48 PM 3/22/03, you wrote:
> >I have all of my 12V electronics - blinkers, headlights etc. hardwired to
> >one of my batteries in my 36V 1960 electric shopper. From the hardwire, it
> >goes through a fuse box, with a 15amp fuse on each seperate accessory.
> >Everything works just fine aside from the stereo.
>
> Tapping the pack is a BAD practice. Don't do this.
>
> I have some 200 watt DC-DC converters (somewhere) that will run on
> 36 volts. (Actually, I sold some of these to Rod Wilde. He might have a few
> left.) Use one or more of these instead of tapping the pack.
Those would be the Microverter moduals. Bill was good enough to let 5 of them come my
way
years ago. They are about the size of a deck of playing cards, 36V in, 12-15V
adjustable
out, at up to 17 amps! I use one adequately heat sinked, in the Heavy Metal Garden
Tractor, and it has performed flawlessly. I back it up with a 13 ahr Hawker Genesis,
and
the combo of the 17 continuous amps from the DC-DC and the stout backup juice from the
Hawker, keeps my garden tractor's 144 watt (rms) stereo system rock'n hard! I set it
up,
so that when the tractor is off, the DC-DC keeps the Hawker floating at 12.95V and the
Emeter powered up at all times...when the ign. key is on, the output voltage swings up
to
14.3V.
> I repeat: Tapping the pack is BAD practice. It is really tough on
> your batteries. One battery will not get enough charge and the others will
> be massively overcharged.
Couldn't agree more.
See Ya.....John Wayland
--- End Message ---
--- Begin Message ---
Hello to All,
"Shelton, John D. AW2" wrote:
> All,
> The 691wh listed for the NiZn is more than double that of the yellow
> top's rating of 312wh. So does this mean that if I have a string of twelve
> MB80s, I'll have at least as much total energy as two strings of 12 yellow
> tops run in parralel?
The Evercells give about three times the range under cruise conditions, as lead acid.
800
lbs. of NiZN give the range of 2400 lbs. of lead acid. In colder temps, when lead acid
goes to about half its range, the NiZN give 6 times the range! Want proof? Sheer's 40
lb.
Evercells give an easy 80 ahrs under EV current draws, even in cold weather....a 45 lb.
Optima gives 25 ahrs under the same circumstances...that's 25 ahrs from 45 lbs., vs 80
ahrs from 40 lbs.!
>How many T-145s is this equivalent to?
Red Beastie was a 2600 lb. vehicle before conversion (5300 lbs. after), and it took
2500
lbs. of Trojans to give 120 mile range. Sheer's Honda Accord weighed about 2600 lbs.
before conversion, but only has 800 lbs. of Evercells...he's gone 117 miles on one
charge!
For a mid voltage EV (144V-156V) with strong acceleration and terrific high speed
power,
the Evercells pale next to YT's for high current juice. My own Blue Meanie accelerates
hard because it is very light (2340 lbs.) and yet has a mid level 156V system that
uses up
to 1200 amps for making big HP and torque. In this case, Optimas rein supreme for
acceleration. As the voltage is raised for a given level of power however, the current
requirements drop, so Evercells start to play catch up with lead acid in the area of
power
performance. Over the 200V threshold, you no longer need 1000+ amps for strong
acceleration, and even 500 amps gives lots of power. If you're considering a 200+V car,
Evercell NiZN technology looks mighty good.
For my direct drive minitruck, I'm looking at a 216V system. The completed conversion,
including the battery pack and rad stereo system, should weigh around 2700 lbs. The
Zilla
1KHV motor controller will allow me to dial in fairly low battery pack current limit,
say
400 amps, to protect the Evercells from excessive current draws, but the current
multiplication factor of the controller will still send 1000 amps through the 4-motor
loop
circuit, when the motors are at lower rpms, such as during take-off times, right when
you
need the torque the most. At 500 amps per motor, this will give about 300 ft. lbs. of
torque. Once the vehicle is up to higher speeds, the motor circuit amps will lower as
more
voltage gets sent to the motors, but at this point, the torque requirements have
fallen.
Even considering voltage sag at 300-400 amps, there will be about 75 HP available.
At a nominal pack voltage of 216V, cruise current at 55-60 mph should be in the 35-40
amp
range (my 2340 lb. EV at 156V uses 55-60 amps at this same speed). With an honest 70-80
ahrs of usable EV level reserve from the Evercells, considering higher occasional
currents, that's 100 mile range! Since it's a minitruck with all the batteries under
the
planned remote control hydraulic tilt bed (my forklift experience is finding its way
into
this EV), and since it will only need 35-40 amps at 60 mph, for road trips, I plan on
rolling my 10kw generator into the bed for unlimited freeway cruising and 40-50 mpg gas
mileage...no more trailering the EV to Seattle car shows! The generator will not
noticeably increase drag because there will be no heavy trailer and the drag of two
more
tires, and the height of my generator loaded in the bed and close to the cab, is lower
than the truck's roof, so the aero drag will be insignificant.
I'll be able to arrive to the show, unload the generator, and enjoy pure EV driving.
This EV should have OK 0-60 acceleration in the 9-10 second range, and a reasonable top
speed of 80-ish...perfect for the rolling sound system I want it to be! If I want more
performance, I'll park it and go get Blue Meanie.
See Ya.....John Wayland
--- End Message ---
--- Begin Message ---
Hi Bruce
I was not confuseing threads but try to set an example .
I have not been to a lot of other EV for sale sites but I will give you
this slogging through them is work.
>This only puts further barriers to more EV drivers. If one
> EV newbie gives up in frustration to the ads, we have not
> achieved our goal (it is hard enough as it is).
For some reason I'm always thinking of the people selling these EV's not the
EV buyer who seem to have the world laid at there feet . When I look over
the ads and see the cars going for less that what the parts cost and all the
time spent doing all the little things that need to be done to make one work
. "EV newbie gives up in frustration to the ads" Lets hope they have more
back bone that this . But I'm getting off the subjust.
> Mike has a successful site. Perhaps instead of others
> starting another EV for Sale site, they could work with
> Mike. Their effort would be like a team player, instead of
> as competition.
I would like to be a team player but don't want to be a hog. Should I have
all my EV's that are for sale on Mike's site ? wouldn't this just be taking
advantage of a good thing .
What if EV parts had all there parts on the web site? ( I know we're just
talking about car's ) . It would not supprize me if someday Mike has to
limite one ad per person to keep things at a managable size.
A while back I was talking to Jon (The self apponited sale man who
instead of paying for the EV I build him is selling it for me while he
drives it) about selling other people's EV's on the web site that he made
and maintains. I was just trying to do somthing good not confuse people.
Jon is into making money and dosen't see were having nicer conversions
selling for less money on "our " web site makes any sence . Show's you how
bissnesss minded I am.
These are just my thoughs and am just trying to keep enough EMF (enough
money flowing) to keep this EV motor going.
> It more exciting to strike out on your own like an
> entrepreneur, than to make a coordinated effort with an
> established site.
It's not exciting at all its just working with what there is and trying to
make somthing happen. If you got a plan let me know.
If a EV garage opened in my town tommorow I'd apply for a job.
> As usual, do not take anything personal, but in the
> spirit of trying to be helpful to the EV community
My feeling also.
Steve Clunn
----- Original Message -----
From: "Bruce EVangel Parmenter" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Sunday, March 23, 2003 2:55 PM
Subject: Re: ZAP RAP FEVER: page to sell or trade your EV
> In
> http://autos.groups.yahoo.com/group/EVList/message/37735
> the second half of the POST, 1sclunn has confused the
> EV for sale topic with EV charging. This thread was not
> about EV charging but a multitude of EV for sale sites
> which can cause a hardship to the EV newbie. I only
> respond to
> http://autos.groups.yahoo.com/group/EVList/message/37735
> to try to minimize confusion and ask that people read my
> original POST
> http://autos.groups.yahoo.com/group/EVList/message/37698
>
> For those that are not aspiring EV for sale site owners,
> and are the weary who have had to slog through the many
> EV for sale sites, my POST was to state what is obvious
> to the latter and possibly ask for call for a
> coordination of efforts.
>
> As usual, do not take anything personal, but in the
> spirit of trying to be helpful to the EV community.
>
> IMHO:
> The EV community was not at the point of 'making money'
> with the EV for Sale sites like broker when production
> EV were available. Now that they aren't the EV community
> is even less so. To ask for money is to reduce the
> number fo people that would drive Electric. These times
> are hard enough for EV drivers that to put up a toll.
>
> With everybody and his brother making an EV for Sale site
> and the advertisers not asked to provide the same basic
> EV information, it becomes a nightmare for the newbie
> EV buyer to know what the EV that is for sale, really is
> (how many batteries, what type, how old, what charger,
> controller, motor, etc.).
>
> This only puts further barriers to more EV drivers. If one
> EV newbie gives up in frustration to the ads, we have not
> achieved our goal (it is hard enough as it is).
>
> Mike has a successful site. Perhaps instead of others
> starting another EV for Sale site, they could work with
> Mike. Their effort would be like a team player, instead of
> as competition.
>
> This could be whatever they decide would help with the work
> load and bandwidth.
>
> But as I stated in
> http://autos.groups.yahoo.com/group/EVList/message/37698
> I have resigned to:
>
> "no one is going to following this. Its too organized,
> and no fun."
>
> It more exciting to strike out on your own like an
> entrepreneur, than to make a coordinated effort with an
> established site.
>
>
>
> =====
> ' ____
> ~/__|o\__
> '@----- @'---(=
> http://geocities.com/brucedp/
> EV List Editor & RE newswires
> (originator of the above ASCII art)
> =====
>
> __________________________________________________
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> Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop!
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