EV Digest 3942
Topics covered in this issue include:
1) Fwd: Re: High current draw from floodies, was RE: Motor Amps, Battery Amps
?
by Dave Cover <[EMAIL PROTECTED]>
2) Pot box for Comutacar?
by jon <[EMAIL PROTECTED]>
3) Fwd: Re: MagneChargers on eBay
by Dave Cover <[EMAIL PROTECTED]>
4) Re: MagneChargers on eBay
by [EMAIL PROTECTED]
5) Re: Fwd: Re: MagneChargers on eBay
by Chris Zach <[EMAIL PROTECTED]>
6) Li-Ion Batteries
by "Ed Rowan" <[EMAIL PROTECTED]>
7) Anyone got a little pot?
by [EMAIL PROTECTED]
8) RE: Sealed PbA battery Options
by "John Westlund" <[EMAIL PROTECTED]>
9) Re: Sealed PbA battery Options
by "Rich Rudman" <[EMAIL PROTECTED]>
10) 35 feet
by Jeff Shanab <[EMAIL PROTECTED]>
11) Re: Motor Amps, Battery Amps ?
by "Rich Rudman" <[EMAIL PROTECTED]>
12) Re: 35 feet
by "Rich Rudman" <[EMAIL PROTECTED]>
13) Re: LRR vs. traction
by "George S." <[EMAIL PROTECTED]>
14) Re: Gear Shopping
by Dragan Stancevic <[EMAIL PROTECTED]>
15) Re: Sealed PbA battery Options
by "Rich Rudman" <[EMAIL PROTECTED]>
16) Re: Fwd: Re: High current draw from floodies, was RE: Motor Amps, Battery
Amps ?
by Lee Hart <[EMAIL PROTECTED]>
17) Re: Motor Amps, Battery Amps ?
by Nick Viera <[EMAIL PROTECTED]>
18) Re: Anyone got a little pot?
by David Chapman <[EMAIL PROTECTED]>
19) RE: Sealed PbA battery Options
by "Roger Stockton" <[EMAIL PROTECTED]>
20) RE: Motor Amps, Battery Amps ?
by "Markus L" <[EMAIL PROTECTED]>
21) Re: Motor Amps, Battery Amps ?
by Evan Tuer <[EMAIL PROTECTED]>
22) Re: Anyone got a little pot?
by Neon John <[EMAIL PROTECTED]>
23) Re: Sealed PbA battery Options
by "John Bryan" <[EMAIL PROTECTED]>
24) Re: Spare Tires (getting OT?)
by [EMAIL PROTECTED]
--- Begin Message ---
--- Lee Hart <[EMAIL PROTECTED]> wrote:
> Yes, this will help. The key point is that a *reversed* cell will stay
> at less than 2v no matter how long it sits -- only charging will bring
> it back. A *dead* cell will bounce back up over 2v within a few minutes
> after the load is removed.
Newbie question: Whats the difference between a reversed cell and a dead cell?
Is a reversed cell
salvagable?
Dave Cover
--- End Message ---
--- Begin Message ---
I am looking for a Pot(entionmeter) Box for my Comutacar. I am in the
process of upgrading to a Curtis 1209 controller. I sure will be nice
having more than 3 forward "speeds". :-)
Does anyone have one to sell? Or, can point me to an affordable source?
Thanks,
Jon
--- End Message ---
--- Begin Message ---
--- Christopher Zach <[EMAIL PROTECTED]> wrote:
> Hm. I'd be very interested in the floor chargers and I live on East
> Coast. Anyone want to split?
>
> Chris
> [EMAIL PROTECTED] wrote:
> > Sorry if this is a repeat, but I never saw my previous post. Anyone need 5
> > of
> > these?
> >
> > http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7936173374
> >
I'm in CT and trying to put together an EV. Could I use any of this for
charging a NiCad pack? Is
this only good for someone with a MagnaCharger equiped vehicle?
Dave Cover
--- End Message ---
--- Begin Message ---
<< I'm in CT and trying to put together an EV. Could I use any of this for
charging a NiCad pack? Is this only good for someone with a MagnaCharger
equiped vehicle? >>
Guess you could find someone selling the on-board part needed to complete the
circuit, but I've never seen *those* for sale on eBay! Without this part, no,
these won't work for anyone else.
--- End Message ---
--- Begin Message ---
I'm in CT and trying to put together an EV. Could I use any of this for
charging a NiCad pack? Is
this only good for someone with a MagnaCharger equiped vehicle?
Right. I have seen the MC sockets on Ebay once, not sure if the 220
computer was included (the brains of the show). Without that it's just a
big half of a transformer.
I'm always on the lookout for another MC slot, as I want to put the
Elec-Trak on inductive charge.
Chris
--- End Message ---
--- Begin Message ---
Looks like a Canadian company, Alternativ Canada is making EV's
with Lithium-ion batteries for lease. Story is at
<http://powerelectronics.com/news/electric-vehicles-li-ion/>
The battery manufacturer, Valence Technology Inc. has a web page
at http://www.valence.com/ucharge.asp
They have some discharge curves comparing their product to lead
acid but I didn't see any prices so if you are interested, guess you
have to give them a call.
Ed Rowan
--- End Message ---
--- Begin Message ---
...for a Magura, that is! The potentiometer on my twist-grip seems to have a few
hundred k-ohms and doesn't respond to turning, so where do I get just this part?
Seems a waste to discard the rest of a perfectly good throttle.
--- End Message ---
--- Begin Message ---
Thanks for the info, Roger.
Roger Stockton wrote:
>The [EMAIL PROTECTED] = 50Ah C/2 *is* the manufacturer's
>spec. and is available
>on the Optima website.
>
>As I recall, it used to be [EMAIL PROTECTED] (=52Ah), but
>dropped to the
>present value at the same time as Optima downgraded
>the C/20 rating.
I've always been fairly critical of manufacturer's specs,
but I cannot think of any explanation as to how others can
claim certain ranges on their conversions other than that
the manufacturer's specs would be correct. But this goes
contrary to another set of data provided by a complete
expert in this field, who also happens to make an awesome
charger. :)
Whatever the case may be, it's good to know that worst case
scenario, I'll have about 25-27 miles per charge to 80% DoD.
I'm curious as to how the descrepancies between both data
came about, but I at least know under careful driving my
range needs can be met.
If my range happens to match the manufacturer's specs and
what others have claimed, it will be just another bonus. As
then I'll have decent range and decent performance, for <
$15k.
Roger Stockton wrote:
>The [EMAIL PROTECTED] rating is at 80F; obviously I didn't
>get the full capacity
>at 68F, but as I recall what I got was between 80
>100% of rated capacity
>(and this from the set of YT blems that I got from
>Ralph Merwin after
>he'd run them in his Prism until he couldn't make
>his commute any
>longer, and then pulled them out and left them sit
>in his garage until
>he got tired of tripping over them, not brand new
>batteries).
Those things must be very forgiving. Good to know, since
they are also expensive. I did come across posts in the
archives of people heavily abusing them and only getting
6,000 miles from them, but on the flip side I've seen posts
of people moderately abusing them and getting 5 or 6 years
life out of them. I also know of AC Propulsion's figures,
where a pack of 28 of them will last 30,000 miles before
they are delivering 80% of their capacity.
Roger Stockton wrote:
>The following Hawker data suggests the
>difference between 80F and 60F would not explain a
>difference between
>the ~0.5kWh spec'd and the 0.28-0.32kWh Rich is
>seeing
I just can't stop wondering where that difference came
about. The numbers you provide matches with what I suspected
before Rich gave me his numbers, and matches the simulations
I ran, and others' statements on their conversions. 1/2 a
kWh per module would mean some very good range. I'll wait
and see how it turns out.
Roger Stockton wrote:
>I believe the number John Wayland put on the list a
>long, long time ago
>was that YTs are good for about 40Ah C/1 in EV use.
That would also match what Bill Dube has seen in his
'Wabbit'. If this case happens to be the one when I have my
conversion running, that would be about 40-45 miles to 80%
DoD at 60 MPH, perhaps about 55-60 miles cycle range to 80%
DoD, maybe 30 miles with lead foot and driving like a
Maniac. I'll just end up expecting 20 miles usable range,
and if I get more than that, I'll be very happy.
Enjoy your vacation, and thanks for your words. I'll look at
the data whenever you place it up, but I'm in no hurry. It
will be a year or so before I need to purchase my battery
pack, which will be the last thing I buy.
Until now, I'll keep debating in my head whether to take
Optimas or Exides, and keep on looking for more information.
I've got plenty of time.
Also, to Reverend Gadget. I should have contacted you about
this, but never got around to it. About your Spitfire, I
found a nice 1969 Triumph GT6+, in running condition being
sold near my city for very cheap(Wont say how much or where
in case some lurker happens to figure it out and wants to
snatch it). It had already in it a Triumph TR6
transmission(without overdrive), TR6 rear axel, and TR6
engine. Body was in good shape, checked the rocker panels
and bulkhead with a magnet and they were excellent.
Breaklines and master cylinder worked great. Body in okay
condition, no bondo but some rust spots that will need
repair. Painted over bright yellow with a real tacky-looking
paintjob to make it half-assed presentable, but it's obvious
where the rust spots are as it wasn't unethically saturated
with bondo. Even got taken for a ride in it, owner claimed
0-60 in 6.5, seat of pants estimate seems to put it about
right there; it was just on par with my dad's Audi TT.
Unless someone grabs it before I do, I probably won't be
looking at shipping your Spit from Cali. The GT6 has a Cd of
about .32, this particular one weighs about 1,800 pounds as
is with its upgrades(Glider weight proably will be around
1,200 without bumpers or ICE parts since the TR6 engine
alone is about 350 pounds), so it could easily dip into the
140 wh/mile territory at 60 MPH with the right drag
reductions(Get the Cd down to about .27-.28 using basic EV
body mod techniques, without even needing to cover rear
wheel wells) and provide excellent range and acceleration.
With a fiberglass bonnet, doors, trunk, and lighter windows,
this may end up weighing less than the 156V Blue Meanie
while having a 240V battery pack(That's a big maybe, but
racers using fiberglass parts and full fiberglass body have
gotten GT6s down to the sub 1,300 pound territory! What I
plan to use will shave off at least 100 pounds, add to that
a severely stripped interior), assuming I get the chance to
mutilate this beautiful car like I intend. I'll see how
things go. Thanks for your offer of a free glider though.
Who knows how things will turn out.
--- End Message ---
--- Begin Message ---
Rich Brown had twin Raptors, twin 8s and a two speed tranny.
We have not heard much from him in a While..
Me Wayland and Rich Brown have actually raced a lot together. John Bryan,
always had number that I felt were a bit too good.
The trick for good results is to keep the tranny, and use the gears, this
lets you make the best use of the power on hand. Directy drive CAN work,
with effort.
Rear drive and gears and 1200 amps can make quite a impression.
10 Deg advance, hand lapped in brushes, polished and stoned to a mirror
finish, and 1000 amps will be nothing on that 9" that it can't handle.
We have used the 170 volt arc limit that Otmar recomends. Add motor voltage
until it arcs, back it off. I have dumped 1300 amps into a 8 with the GP
controller, since it's mine...
The 8" had arc signs at over 1300 and they had rock damage by then. Simply
put, with 264 volts on hand you should a gone for the Zilla 2K. You can just
keep the motor amps railed for longer.
Loose about 1000 lbs of car weight... That helps imensily.
----- Original Message -----
From: "John Westlund" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, December 02, 2004 1:32 PM
Subject: Re: Sealed PbA battery Options
> Rich Rudman wrote:
>
> >If you paid for the Zilla, and have the high voltage
> >one, More volts is
> >always better. Getting all 1000 amps to the motor
> >all way down the drag
> >strip is the trick.
> >14s and 15 are possible on paper, it's a lot harder
> >to make it happen on
> >command.
>
> On paper, the ADC9'' motor gets all 1,000 motor amps up to
> about 3,500-4,000 RPM, depending on variables used, and
> assuming a 204V motor voltage limit.
>
> But I remember Berube's comments on simulations. That, and
> problems will likely occur throwing that kind of power into
> that motor.
>
> 600 amps, 192V in a 2,500 pound car is good for 19 second
> 1/4 mile drags, and 0-40 mph acceleration good enough to
> embarass a $40,000 sports car, as evidenced by John Bryan's
> beautiful VW, and John Wayland with 1,200 amps, an ADC9'',
> and 156V can take his 2,350 pound Meanie from 0-60 in < 6
> seconds, while with 800 amps it took 8 seconds. I remember
> him claiming in one of his posts, if he were to race Meanie
> using his current setup, it might pull high 14s in the
> 1/4(With the 1,200 amps). Rich Brown, using 144V, two
> ADC8'', and a Raptor 1200 can pull low 15s/high 14s, with a
> 3,100 pound curb weight. It looks to be very possible to
> high 14s/low 15s with 1,000 amps and a 204 motor volt limit
> on a 2,500 pound conversion, but I'll wait and see after I
> get an EV going. 18-19 seconds still wouldn't be that bad.
>
> Rich Rudman wrote:
>
> >All I am getting is about 26 amp hours of taxable
> >load from The Orbs.. I am
> >sure once I get the load fast enough, I can heat
> >them in about 3 cycles from
> >60 to 100 Deg F. I will try to log a run at 80 Deg F
> >some time soon.
>
> Thanks. I'm interested in these results, and the data that
> Roger Stockton claims to have. As it is, I'm certainly
> leaning towards the Orbitals, simply because they are about
> 1/2 the price of the Optimas.
>
--- End Message ---
--- Begin Message ---
I and the others who measured out the cones estimateed the footage in
the stopbox by visual observation.
I head into the box at a constant 60 and when I cross the line I use the
4 wheel and the clutch as brakes, The G analyst topped out at 2.5
I don't know if it could read above that, it was stolen before I could
verfy :-(
I out autocrossed the stock vetts and 5.0's was working on the ZR1's
when I had to stop.
one side note, there was a cloud of dust when I did this, At first I
thought it was smoke. Without makeing a squeal I left black stripes 10"
wide from all four wheels but the majority of the powder was the front
brake shoes, basically gone in one day.
It was definetly under 50 feet there wasn't that many cones.
Oh and it was on the tarmac not asphault.
--- End Message ---
--- Begin Message ---
OK... I have been staying out of this because I have my own fish to fry.
BUT
Points... if the yellow LED is ON it means the controller is WOT, infact
it's locking the FETs on at 100% pwm, and just kicking them off evey 1/2
second to make sure the amps are still sane.
If the Yellow led is on, The controller is NOT doing current multipliction,
the batteries are just locked onto the motor leads. AND that's all you get.
I limp home and recharge when this happens.....
So... weak batteries, Huge battery cable losses, bad or fried motor
brushes... All sorts of things. But it's NOT the controller folks.
First Nick, put the Shunt in the main Battery Negative lead. STomp on it,
record the max amps. Getting the complete pack voltage at this point tells
you Everything you need to know.
First select first gear, then apply as much foot as you dare.... If your
voltage on the controller B+ to B- drops like a rock, then you have battery
and cabling issues. If the voltage stays the same and the amps don't go
anywhere, then your motor is just not drawing any amps. Look for real issues
in the motor.
And remember that Red beastie had a 450 amp Raptor and 120 volts and was
5200 lbs, and had acceptable power levels. Not real good, but it could get
to 70 mph, with about a minute of time. With a Raptor 1200 in her we could
fry any and all the contactors.....Been there done that got the Flu doing
it...
Starting in 4th with a 120 volt pack looking at the current in the motor +
to the B- loop you should see 600 amps or more until the yellow comes on
then 600 or less.
In fact if you ARE looking at motor amps and see anything over 750 amps GET
OFF it!!! Just to keep the diodes in the non vapor phase.
Don't do the high gear full amps launches if you don't have to. Use the
lowest gear and the highest motor RPM you can stand.
Yes a good Raptor 600 will peg a 500 amp gage without much fuss or effort.
If... the motor is up to it.
.
----- Original Message -----
From: "Roger Stockton" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, December 02, 2004 3:05 PM
Subject: RE: Motor Amps, Battery Amps ?
> > Nick Viera <[EMAIL PROTECTED]> wrote:
> > > Hi,
> > >
> > > Here's something which I've wondered about for a while:
> > >
> > > I have a Raptor 600 controller, on which I have the
> > > potentiometer for current limit turned all the way up
> > > (max current). I have a 0-400 amp ammeter on the battery
> > > side of the controller, with the shunt inserted between
> > > the controller/motor (-) buss bar and the (-) contactor.
> > >
> >
> > > My biggest problem is that my acceleration in the higher
> > > gears is horrible because I can't seem to pull enough
> > > current from the batteries. I realize that this is
> > > probably because the Raptor is hitting it's max output
> > > of 600 motor amps and is going into current limit as the
> > > LEDs indicate (In fact, according to the LEDs, my
> > > controller is always in current limit when I floor it, no
> > > matter what gear).
>
> I'm quite late jumping in here, but something that has been bugging me
> that nobody has addressed is why Nick is getting such pitiful current
> from his controller in any case.
>
> That is, the DCP Raptor 600 is limited to a maximum of 600 *battery*
> amps, not motor amps. Motor/freewheel amps are "unlimited" (~900A).
> The current limit adjust allows the battery current limit to be adjusted
> from 50-600A.
>
> Nick has a 400A shunt monitoring the battery current and says he has the
> battery current limit cranked all the way up, yet he isn't able to peg
> his ammeter (ever?), even though the Raptor has its yellow LED lit
> (which apparently indicates that it is in current limit).
>
> So, why isn't Nick seeing a solid 600A (or at least a pegged 400A meter)
> for at least the first few seconds when he floorboards the throttle
> while the controller is cold? I could understand thermal cutback
> limiting him once the controller warms up, but surely he ought to be
> able to see 600 battery amps at least briefly.
>
> If he is not pegging his 400A meter, then he's getting less than 2/3 of
> the power that his controller is capable of, which at low RPM means less
> than 2/3 of the torque.
>
> 600 motor amps is Curtis level performance; the DCP controller are
> supposed to do a lot better than this...
>
> Anybody more intimately familiar with the DCP controllers care to
> explain this one?
>
> Cheers,
>
> Roger.
>
--- End Message ---
--- Begin Message ---
I believe you...
The G-anylist rails at 2.56 Gs...
We have one and have tested Gone Postal acceleration with it.
The 3.5 Gs is suspect, since that takes down force and active airfoils for
CART and F1 to achieve.
I don't think the Solo II guys in E Mod do that. those wings sure do
help....
The best I ever got was 1.06 Gs with Auto cross rubber and this was in a
Rather prepped street Stang. I had PorterFields on all 4 corners. There was
not much that I could not out brake.
The Darn Vetts could kill with ABS, and RE71R, and other Slick just barley
legal race rubber.
brake dust is common, so is rubber dust from not quite sliding, done right
there is rubber haze... and no screaching.
>From somebody that CAN to 1 G stops without ABS.... 3.5 Gs, has to be
measured for me to buy....
OK what kind of truck???? who's make what tricks.... I need to know, since
the next Madman machine will be a truck and at least 500Kw of some sort of
drive.
That Zilla 2K needs a home... and I need a home for tubbed tires and a
narrowed 9 incher.
Bob Salem, NO it won't be a front driver.. I have learned my lessons.
----- Original Message -----
From: "Jeff Shanab" <[EMAIL PROTECTED]>
To: "EVlist" <[EMAIL PROTECTED]>
Sent: Thursday, December 02, 2004 7:51 PM
Subject: 35 feet
> I and the others who measured out the cones estimateed the footage in
> the stopbox by visual observation.
>
> I head into the box at a constant 60 and when I cross the line I use the
> 4 wheel and the clutch as brakes, The G analyst topped out at 2.5
> I don't know if it could read above that, it was stolen before I could
> verfy :-(
>
> I out autocrossed the stock vetts and 5.0's was working on the ZR1's
> when I had to stop.
>
> one side note, there was a cloud of dust when I did this, At first I
> thought it was smoke. Without makeing a squeal I left black stripes 10"
> wide from all four wheels but the majority of the powder was the front
> brake shoes, basically gone in one day.
>
> It was definetly under 50 feet there wasn't that many cones.
>
> Oh and it was on the tarmac not asphault.
>
--- End Message ---
--- Begin Message ---
Hi all
On my EV I have used 185/55x13 Invictas, 205/60x14 tires and Proxima RRs
175/65x14.
The Proximas are by far the best tires I have used for EV use. The wide
tires may handle
a bit better but the Proximas handle corners well also.
The Proxima has very soft sidewalls, a Treadwear rating of 200(the same as
one of the most
popular autocross street tires the Falken Azinis) and a high pressure rating.
It would not be a very good autocross tire because of the soft sidewalls
but on my EV they make
a great street tire. The only problem I have with them is availability.
The EV1 was a great car but not really a sports car, it had a lot of body
lean in corners and that
narrow rear track didn't help anything except help reduce aero drag.
I had an EV1 for 6 months and I could out corner it with the same tires on
my Rabbit truck EV.
But the EV1 could out drag most cars on freeway onramps.
EV1 drivers who tended to rub curbs had problems with the thin sidewalls of
the tires, GM replaced
some for this reason.
George S.
144V Rabbit pickup
---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.773 / Virus Database: 520 - Release Date: 10/5/04
--- End Message ---
--- Begin Message ---
On Thursday 02 December 2004 15:48, David Chapman wrote:
> Might try Browning Gear, they would have universal app gears for conveyors
> as well as shaft bearings. Or google on industrial gears and similar. You
> will need to spec torque load and speed etc. DC.
Thanks, I'll look it up.
--
Peace can only come as a natural consequence
of universal enlightenment. -Dr. Nikola Tesla
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: "John Westlund" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, December 02, 2004 7:34 PM
Subject: RE: Sealed PbA battery Options
> Thanks for the info, Roger.
>
> Roger Stockton wrote:
>
>
> >The following Hawker data suggests the
> >difference between 80F and 60F would not explain a
> >difference between
> >the ~0.5kWh spec'd and the 0.28-0.32kWh Rich is
> >seeing
>
Roger...
I have never see 500 watt hours for a YTs, even at 120 Deg F case
temps and 500 watt loads.
This is where doing real data testing helps.
I certialy can not turst the spec sheets, and I only trust my own test
gear. The Standard test for me is two loads at 1500 watts, and 110 amps of
recharge, then the last test while hot is at 750 watts.
This is the bench mark that I am using. I record Kwhr off my Link 2000R and
Heart Freedom 25.
The latest test on the Monster charger is different since I have a bunch of
other things to monitor... like not blowing up $25,000 worth of chargers,
Windloaders and battery packs.
I am trying to keep it kinda loose, and let folks know my difficuilties,
since you all have them, and so do I.
When I have 3 digit data, that I believe I will get it on the download
section.
Certainly 120 Deg F and 2.75 amps of draw would really allow for some
dramatic capacity improvemnts
> I just can't stop wondering where that difference came
> about. The numbers you provide matches with what I suspected
> before Rich gave me his numbers, and matches the simulations
> I ran, and others' statements on their conversions. 1/2 a
> kWh per module would mean some very good range. I'll wait
> and see how it turns out.
>
> Roger Stockton wrote:
>
> >I believe the number John Wayland put on the list a
> >long, long time ago
> >was that YTs are good for about 40Ah C/1 in EV use.
>
--- End Message ---
--- Begin Message ---
Dave Cover wrote:
> Newbie question: Whats the difference between a reversed cell and
> a dead cell? Is a reversed cell salvagable?
Most types of batteries use two different metals for their two
electrodes; carbon-zinc, nickel-cadmium, nickel-iron, etc. The
electrolyte is just a current carrier; it does not participate in the
chemical reactions.
The lead-acid cell is unique in that *both* plates are lead, and the
acid electrolyte is the second electrode. Therefore, you can charge a
lead-acid battery with either polarity, and it still works. One of the
plates winds up at the same potential as the electrolyte, and the other
will be 2v away from it.
But as a practical matter, the "+" and "-" plates in all modern
lead-acid batteries are built differently to optimize them for their
intended polarity. Like left and right shoes, you get far better results
if you use them the right way! :-)
When the cells are manufactured, they are given a "forming" charge which
establishes this polarity. Henceforth, "+" must always be about 2v more
positive than "-" or you destroy this formation.
When you run a lead-acid cell totally dead (0v), all the acid gets
converted into lead sulfate. This leaves nothing but water as the
electrolyte. Water is a poor conductor, so you basically have a
resistor. A single lead-acid cell all by itself can't normally be run
this dead, unless you leave a load connected for weeks. Its resistance
gets so high that the current it delivers becomes negligible.
But if you do leave it dead for days, the lead sulfate gradually
crystalizes, and cracks free from the plates. Now it is no longer
electrically connected; and you can't recharge it. The battery is
"sulfated". This is why you don't want to leave a lead-acid battery
deeply discharged for very long; the longer it sits that way, the harder
it will be to recharge, and the less amphour capacity you will be able
to get in the future.
When you run many lead-acid cells in series, it is far easier to run a
cell completely dead. It is possible for one cell to go completely dead
while there is still charge left in the rest. As you keep drawing
current from the battery, the dead cell's voltage is first forced to
zero (dead). If you keep discharging the already-dead 0v cell, it
*reverses* to -2v. You are now "forming" the cell with a reversed
polarity -- it is actually charging in the wrong direction. This is
called "reversing" the cell.
Once a cell is reversed, it *stays* reversed. It will act like a normal
lead-acid battery, but with the "+" and "-" terminals reversed. But, its
amphour capacity, internal resistance, and life are all considerably
less than normal.
To fix this, you need to re-reverse its charge -- run it completely dead
again, and then recharge it in the normal direction. This will take a
*lot* of charging! In effect, you have to give it a new "forming"
charge, which takes many more amphours than any normal charge. And when
you are done, what you have is a battery with seriously reduced amphour
capacity and life.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Hi,
> Points... if the yellow LED is ON it means the controller is WOT,
> infact it's locking the FETs on at 100% pwm, and just kicking them off
> evey 1/2 second to make sure the amps are still sane.
The yellow WOT throttle LED on my Raptor *NEVER* comes on, even with the
throttle to the floor (regardless of gear). According to the manual,
this indicates that the throttle IS in current limit mode.
There has only been two times ever that the yellow led has lit during
driving. Both times the batteries were very low, and I was flooring it
in first gear and getting nowhere fast (I was basically out of power and
I luckily just barely reached my destination).
And I do believe my throttle setting is correct on the Raptor, as with
the motor DISCONNECTED, I DO get the yellow LED to light up when I floor
the throttle.
> But it's NOT the controller folks
The only reason why I doubt this controller at times is because it has
had previous problems. Luckily, once I replaced the two connectors
between the power board and control board, I solved my cutting-out
problem (after being stranded with a NON-working controller on the side
of the road three times). After the new connectors were installed I did
notice the controller being A LOT more responsive, and it hasn't cut-out
since.
> First Nick, put the Shunt in the main Battery Negative lead. STomp on
> it, record the max amps
That is where the shunt is installed. In 1st gear, on warm batteries, I
can and do get it to go just up to 400 amps, or peg (if I'm lucky). In
2nd gear, I can usually get it around 360 amps (maybe just a bit more if
I'm lucky). 3rd gear is the impossible one. I've never seen more than
about 270 battery amps when flooring it. Keep in mind again that the
yellow LED has NEVER come on under these conditions.
Also, getting 400 amps in 1st gear doesn't help me much as I can't go
much past 25mph before the motor is at 5000 rpms. I really need the
power in 2nd and in 3rd gear, where I rarely am seeing it.
I will continue to monitor all of this...
> Red beastie had a 450 amp Raptor and 120 volts and was
> 5200 lbs, and had acceptable power levels. Not real good, but it could get
> to 70 mph, with about a minute of time.
This just seems to further indicate that I have a real problem with my
setup. I basically at this point CANNOT top ~59mph on a flat surface
(less on any sort of grade), and can just barely hold 45mph going up
longer/steeper hills. and It takes me a lot of time to get up to 55mph.
This in a vehicle that I believe to be around 4000lbs.
> Starting in 4th with a 120 volt pack looking at the current in the
> motor + to the B- loop you should see 600 amps or more until the
> yellow comes on then 600 or less.
I absolutely CANNOT start in 4th gear (not even in 3rd). I floor it and
I might just barely inch forward on flat surface. Sometimes the motor
goes into a stall condition (I'm putting in power but not moving). Still
no yellow LED.
Thanks for taking the time to comment. I'm sorry if I'm repeating
myself, but I'm puzzled and haven't made been able to make much forward
progress with this "issue."
I am still working on getting some of Lee's battery bride LEDs hooked up
(If I can ever find somebody who sells >1/2 watt 1% resistors), and I'm
probably going to get a 1000 amp ammeter and shunt to place in the motor
loop so I can monitor it (though I'm not too eager about buying another
Westach product).
Thanks again for everyone's input in this unfolding story about the
little Jeep EV that could :-)
-Nick
1988 Jeep Cherokee 4x4 EV
http://Go.DriveEV.com/
------------------------------------------------
On Thu, 2004-12-02 at 22:09, Rich Rudman wrote:
> OK... I have been staying out of this because I have my own fish to fry.
>
> BUT
> Points... if the yellow LED is ON it means the controller is WOT, infact
> it's locking the FETs on at 100% pwm, and just kicking them off evey 1/2
> second to make sure the amps are still sane.
>
> If the Yellow led is on, The controller is NOT doing current multipliction,
> the batteries are just locked onto the motor leads. AND that's all you get.
> I limp home and recharge when this happens.....
>
> So... weak batteries, Huge battery cable losses, bad or fried motor
> brushes... All sorts of things. But it's NOT the controller folks.
>
> First Nick, put the Shunt in the main Battery Negative lead. STomp on it,
> record the max amps. Getting the complete pack voltage at this point tells
> you Everything you need to know.
> First select first gear, then apply as much foot as you dare.... If your
> voltage on the controller B+ to B- drops like a rock, then you have battery
> and cabling issues. If the voltage stays the same and the amps don't go
> anywhere, then your motor is just not drawing any amps. Look for real issues
> in the motor.
>
> And remember that Red beastie had a 450 amp Raptor and 120 volts and was
> 5200 lbs, and had acceptable power levels. Not real good, but it could get
> to 70 mph, with about a minute of time. With a Raptor 1200 in her we could
> fry any and all the contactors.....Been there done that got the Flu doing
> it...
>
> Starting in 4th with a 120 volt pack looking at the current in the motor +
> to the B- loop you should see 600 amps or more until the yellow comes on
> then 600 or less.
> In fact if you ARE looking at motor amps and see anything over 750 amps GET
> OFF it!!! Just to keep the diodes in the non vapor phase.
> Don't do the high gear full amps launches if you don't have to. Use the
> lowest gear and the highest motor RPM you can stand.
> Yes a good Raptor 600 will peg a 500 amp gage without much fuss or effort.
> If... the motor is up to it.
>
>
>
>
> .
>
> ----- Original Message -----
> From: "Roger Stockton" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: Thursday, December 02, 2004 3:05 PM
> Subject: RE: Motor Amps, Battery Amps ?
>
>
> > > Nick Viera <[EMAIL PROTECTED]> wrote:
> > > > Hi,
> > > >
> > > > Here's something which I've wondered about for a while:
> > > >
> > > > I have a Raptor 600 controller, on which I have the
> > > > potentiometer for current limit turned all the way up
> > > > (max current). I have a 0-400 amp ammeter on the battery
> > > > side of the controller, with the shunt inserted between
> > > > the controller/motor (-) buss bar and the (-) contactor.
> > > >
> > >
> > > > My biggest problem is that my acceleration in the higher
> > > > gears is horrible because I can't seem to pull enough
> > > > current from the batteries. I realize that this is
> > > > probably because the Raptor is hitting it's max output
> > > > of 600 motor amps and is going into current limit as the
> > > > LEDs indicate (In fact, according to the LEDs, my
> > > > controller is always in current limit when I floor it, no
> > > > matter what gear).
> >
> > I'm quite late jumping in here, but something that has been bugging me
> > that nobody has addressed is why Nick is getting such pitiful current
> > from his controller in any case.
> >
> > That is, the DCP Raptor 600 is limited to a maximum of 600 *battery*
> > amps, not motor amps. Motor/freewheel amps are "unlimited" (~900A).
> > The current limit adjust allows the battery current limit to be adjusted
> > from 50-600A.
> >
> > Nick has a 400A shunt monitoring the battery current and says he has the
> > battery current limit cranked all the way up, yet he isn't able to peg
> > his ammeter (ever?), even though the Raptor has its yellow LED lit
> > (which apparently indicates that it is in current limit).
> >
> > So, why isn't Nick seeing a solid 600A (or at least a pegged 400A meter)
> > for at least the first few seconds when he floorboards the throttle
> > while the controller is cold? I could understand thermal cutback
> > limiting him once the controller warms up, but surely he ought to be
> > able to see 600 battery amps at least briefly.
> >
> > If he is not pegging his 400A meter, then he's getting less than 2/3 of
> > the power that his controller is capable of, which at low RPM means less
> > than 2/3 of the torque.
> >
> > 600 motor amps is Curtis level performance; the DCP controller are
> > supposed to do a lot better than this...
> >
> > Anybody more intimately familiar with the DCP controllers care to
> > explain this one?
> >
> > Cheers,
> >
> > Roger.
> >
--- End Message ---
--- Begin Message ---
At 07:26 PM 12/2/04 -0800, you wrote:
...for a Magura, that is! The potentiometer on my twist-grip seems to have
a few
hundred k-ohms and doesn't respond to turning, so where do I get just this
part?
Seems a waste to discard the rest of a perfectly good throttle.
If you can send me a picture and some kind of measurement, specs etc, I
will be glad to look in my bags and bales of pot(s) and see if I can find
you one. David Chapman.
--- End Message ---
--- Begin Message ---
Rich Rudman [mailto:[EMAIL PROTECTED] wrote:
> Roger...
> I have never see 500 watt hours for a YTs, even at
> 120 Deg F case temps and 500 watt loads. This is where doing
> real data testing helps.
If you're suggesting that I haven't done real testing, you're sorely
mistaken Rich.
I've dug up a couple test files at random and sent plots off to John
Westlund. I'll send you a copy too, just for fun.
For anyone else interested, here is a summary of these randomly selected
results:
YT#4
average average
discharge temperature
cycle kWh Ah rate (A) deg.C deg.F
1 0.31 28.6 22.75 13.6 56.4
2 0.32 28.4 22.96 14.5 57.8
3 0.37 32.9 23.09 14.5 58.1
4 0.44 38.6 23.13 15.2 59.4
YT#10:
average average
discharge temperature
cycle kWh Ah rate (A) deg.C deg.F
1 0.57 50.0 23.06 18.0 64.4
2 0.52 45.2 23.21 17.5 63.5
3 0.50 42.9 23.24 17.3 63.1
4 0.51 44.7 23.10 18.0 64.4
5 0.51 44.1 23.20 18.1 64.6
> I certialy can not turst the spec sheets, and I only
> trust my own test gear. The Standard test for me is two loads
> at 1500 watts, and 110 amps of recharge, then the last test
> while hot is at 750 watts. This is the bench mark that I am
> using.
Nothing wrong with that, just don't confuse it with what a YT is rated
for and capable of delivering at a constant 25A load. 750W is
[EMAIL PROTECTED]; obviously these test results will not match up with the
manufacturer's reserve capacity spec'd at 25A constant current.
I don't trust the manufacturer's Ah specs since I don't know the test
conditions they use, but the reserve capacity test conditions are stated
and are those decreed by BCI, so that is a spec I *expect* the batteries
to meet when I reproduce the test conditions.
My test results certainly indicate that the Optima reserve capacity spec
is realistic.
> I record Kwhr off my Link 2000R and Heart Freedom 25.
These tests were logged using an RS232 E-meter.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Nick,
this is just a thought from a novice on the following statement
you made:
> I absolutely CANNOT start in 4th gear (not even in 3rd). I
> floor it and
> I might just barely inch forward on flat surface. Sometimes the motor
> goes into a stall condition (I'm putting in power but not
> moving). Still
> no yellow LED.
What if you bypass (for testing) your controller and use your
main contactors to connect the battery directly to your motor.
Now try to start in 3rd or 4th gear. To be safe you may
try this first with only part of your pack connected. In a sense
you would emulate a contactor controller and see if your
batteries can deliver the current that your motor demands.
You could possibly built a cheapo resistor in there that
a second contactor would bypass to make smoother starts.
Markus
--- End Message ---
--- Begin Message ---
On Thu, 02 Dec 2004 23:47:54 -0600, Nick Viera <[EMAIL PROTECTED]> wrote:
> Hi,
>
> > Points... if the yellow LED is ON it means the controller is WOT,
> > infact it's locking the FETs on at 100% pwm, and just kicking them off
> > evey 1/2 second to make sure the amps are still sane.
>
> The yellow WOT throttle LED on my Raptor *NEVER* comes on, even with the
> throttle to the floor (regardless of gear). According to the manual,
> this indicates that the throttle IS in current limit mode.
If in doubt, use a DC current clamp meter or some other temporary
ammeter on one of the motor cables. You should see it go up to 600A
or whatever the Raptor is set to, while accellerating. If not, check
the controller.
If that's OK, then it's possible you've got a shorted field winding or
something like that.
--- End Message ---
--- Begin Message ---
The Magura throttle on my GoBig scooter was smashed in shipping. I got a
good look at the internals. The pot is a standard off-the-shelf unit that
should be available from DigiKey or equiv. I'm thinking it was a Potter &
Brumfield. As I recall, you can remove that single screw and withdraw the
pot from the socket it fits in. It should have markings.
John
On Thu, 2 Dec 2004 19:26:53 -0800, [EMAIL PROTECTED] wrote:
>...for a Magura, that is! The potentiometer on my twist-grip seems to have a
>few
>hundred k-ohms and doesn't respond to turning, so where do I get just this
>part?
>Seems a waste to discard the rest of a perfectly good throttle.
>
---
John De Armond
[EMAIL PROTECTED]
http://bellsouthpwp.net/j/o/johngd/
Cleveland, Occupied TN
--- End Message ---
--- Begin Message ---
From: "Rich Rudman"
> John Bryan, always had number that I felt were a bit too good.
And I always thought my numbers were embarrasingly bad!
Hey Rich, you beat me in a side by side race at Woodburn....
Here's the numbers from Aug 29th 1998, I was in the left lane,
you were in the right.
Ghia Goldie
R/T .623 .842
60' 2.415 2.9
330 7.518 7.710
1/8 11.865 11.882
MPH 55.46 58.7
1000 15.742 15.528
1/4 19.067 18.649
MPH 67.52 71.62
I've always thought those were numbers best kept to myself,
they don't seem particularly good to me. The only reason my
numbers are so poor though, is that I'm limited to 380 battery amps.
John
--- End Message ---
--- Begin Message ---
<<I don't. I have *never* carried a spare in any of my EVs, for nearly 30
years now.>>
I continue to be amazed when people say this. The last time I saw this
discussion, I said to myself "I can't believe these people have good luck with
their tires! I don't know anyone that does!" Later that *very* same day, I
got a
big ugly screw stuck in a brand new tire. A few weeks later, a piece of an
old clothes hanger penetrated another tire.
About a month later I had a massive blowout, so bad that the tread came
entirely loose and was flapping around hitting my rear fender. I still have
black
marks and scratches on the car from the incident, in addition to a broken
antenna. Oh, this was a fairly new tire.
I always carry a spare, if not two, and I always carry all the equipment
necessary to change the tire on the road, in addition to a flashlight, and even
an
electric pump that I can plug into the cigarette lighter. Yes, flat or blown
tires happens to me that often, and I've been driving for over 20 years now.
And no, I don't drive on tires until they are threadbare, and no I don't buy
tires from a junkyard.
Sam
--- End Message ---
