EV Digest 4674
Topics covered in this issue include:
1) Re: Where to find vidoes of White Zombie?
by "Rich Rudman" <[EMAIL PROTECTED]>
2) AGM battery lifetime
by Mike Barber <[EMAIL PROTECTED]>
3) Vas: Re: Steves Mower, was, 2000 mile range EV?
by Seppo Lindborg <[EMAIL PROTECTED]>
4) Re: Where to find vidoes of White Zombie?
by "Christopher Robison" <[EMAIL PROTECTED]>
5) Re: Driving analog gauges
by Mark Hastings <[EMAIL PROTECTED]>
6) Re: Critical Mass
by "Mark Hanson" <[EMAIL PROTECTED]>
7) Re: Help with battery wiring, avoid looping back
by Rush <[EMAIL PROTECTED]>
8) Re: Re Hep with battery wiring, avoid looping back
by M Bianchi <[EMAIL PROTECTED]>
9) EV's with a cord, Re: Vas: Re: Steves Mower, was, 2000 mile range EV?
by jerry dycus <[EMAIL PROTECTED]>
10) Re: Buses talk...
by Nick Austin <[EMAIL PROTECTED]>
11) Closed tailgate of the truck
by Victor Tikhonov <[EMAIL PROTECTED]>
12) RE: Closed tailgate of the truck
by Tim Humphrey <[EMAIL PROTECTED]>
13) Re: Closed tailgate of the truck
by "EVdave" <[EMAIL PROTECTED]>
14) Re: Siemens EV Motors
by Lee Hart <[EMAIL PROTECTED]>
15) Re: Shunt motor regen setup
by Lee Hart <[EMAIL PROTECTED]>
16) RE: Even better price for AGM, was: Best Flooded Battery
by Cor van de Water <[EMAIL PROTECTED]>
17) Re: Re Hep with battery wiring, avoid looping back
by "Mark McCurdy" <[EMAIL PROTECTED]>
18) Re: Buses talk...
by "damon henry" <[EMAIL PROTECTED]>
19) Re Hep with battery wiring, avoid looping back
by Dave Cover <[EMAIL PROTECTED]>
20) RE: Closed tailgate of the truck
by "Brown, Jay" <[EMAIL PROTECTED]>
--- Begin Message ---
I love it... we have Gassers that just don't believe... I think Johns should
post all his time slips... in Jpeg, AKA actual pictures of the time slips.
Like hey Bud...you got a couple of these???? If not shut up and get out
of the way....
I can attest to the speed run, I was there... I watched from the other
lane... While getting my doors blown into next week. And Goldie is not slow
by any means.
Humm that means I have a 100 mph or something ticket drifting around the
inside of Goldie somewheres I aughta find that one...
I sure would like to be a member of my own 100 mph club...
Madman
----- Original Message -----
From: "john bart" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, September 08, 2005 10:22 AM
Subject: Where to find vidoes of White Zombie?
> Im looking for some videos of white zombie running at the track, i posted
the recent 12.6 sec. 1/4 mile video on a forum i periodically visit
(www.chitownracing.com) and there was a few non believers of the cars
performance. They said they would like to see the video without any
interruptions as far as camera angles changing and so on. Does anyone have
a video, or know where a video is posted like this? Thanks for your help
guys.
>
>
> ---------------------------------
> Click here to donate to the Hurricane Katrina relief effort.
>
--- End Message ---
--- Begin Message ---
What is the lifetime that I can expect from a typical AGM battery pack?
I'll throw in some caveats in hopes to get a good answer:
-Battery management system is used so that the individual batts aren't
charged past gassing voltage
-Same batt mgmt system gets batts equalized to same voltage using bypass
regulation when charging
-Pack is never drawn down past 80% Depth Of Discharge
-Pack is sized to give 50 mile range with fresh pack and 80% DOD
-End of life for pack is when it is able to be charged to only 20% of
initial capability
-Typical driver has heavy foot - routinely makes current draws of 1000A
Some of the info that I have indicates expected cycle life based on DOD.
What this doesn't tell me is what the capacity of the batteries is at end of
life. For instance, if my average commute to and from work is only 10
miles, and this represents 40% DOD, then even if the pack is only able to be
charged to 20% of original capacity, I could still make my commute and not
exceed the 80% DOD.
--- End Message ---
--- Begin Message ---
>
> Lähettäjä: "David Roden" <[EMAIL PROTECTED]>
>
>
> I can't remember where, but I read once about a fellow who actually DID use
> a long extension cord to run his Elec-Trak!
Hey, that brought back a memory from my childhood.
I was a little kid, some 9-10 years old. I was visiting a construction site
where my dad worked. One caterpillar had blown its motor completely at a
critically scheduled project. While waiting for the replacement motor, my
father had made a temporary fix by taking the motor out and installing a big
3-phase electric motor instead. It was connected with a thick cord to the
electricity distribution cabinet beside the working area. They had also built a
rack and a couple of meters long arm behind the driver to carry the cord and
prevent it from getting under the caterpillar.
Obviously it was not too manouverable, they could work only a small area at a
time and the driver had to keep constant watch for the cord. But it was enough
to limp through that task and keep the overall project going.
Seppo
>
>
> David Roden - Akron, Ohio, USA
> EV List Assistant Administrator
>
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>
--- End Message ---
--- Begin Message ---
The video I posted yesterday does have a scene change in the middle, going
from a camera near the burnout to my camera halfway down the track.
However, there is no scene cut between viewing the run and showing the
scoreboard:
http://ohmbre.org/video/woodburn_2005/waylandslastrun.mpeg
If you'd like, I can convert and post the entire clip from just my camera,
which shows from the launch to the scoreboard with no cuts, just some
occasional zoom changes as you see in the video above. It's only a little
over a second (35 frames, IIRC) of additional footage.
--chris
john bart said:
> Im looking for some videos of white zombie running at the track, i posted
> the recent 12.6 sec. 1/4 mile video on a forum i periodically visit
> (www.chitownracing.com) and there was a few non believers of the cars
> performance. They said they would like to see the video without any
> interruptions as far as camera angles changing and so on. Does anyone
> have a video, or know where a video is posted like this? Thanks for your
> help guys.
>
>
> ---------------------------------
> Click here to donate to the Hurricane Katrina relief effort.
>
>
--- End Message ---
--- Begin Message ---
When the EVision comes about maybe Westach could make some custom gauges to run
off of 0-10mA in an analog. They have all those voltage and amp gauges that the
variose evdealers say. They probably already have a gauge that will run off
0-10mA they may just need to paint a new face.
Then there would be a nice professional EV Fuel gauge that looks and feels like
a real automotive gauge.
Victor Tikhonov <[EMAIL PROTECTED]> wrote:
Thanks Paul,
Whoever will use EVision, since most likely will have to take out
the dash anyway, will be required to replace all these garden variety
of gauge types with just a mA meter, say 0-10mA full scale, or
something common. Not a big task, far easier than for me to
accommodate any possible gauge type out there.
Victor
Paul G. wrote:
>
> On Aug 31, 2005, at 1:00 PM, Victor Tikhonov wrote:
>
>> Trying to find what kind of current (or power) standard automotive
>> fuel and temp gauges with moving coil consume, (ball park number)
>> but of course can't find it.
>>
>> It appears that most senders (except for speedometers) are
>> resistive elements wired as rheostats and going from some
>> fixed (tens/hundreds of Ohms) resistance to near zero when the fuel
>> level/temp/whatever changes
>>
>
> Oh, this is where things will get ugly. Many auto fuel gauges are
> thermal type and will read empty when unplugged and may be damaged if
> fed auto 12 volts and then grounded. These often use a regulator to
> supply them power. The catch is this regulator is often a thermal
> vibrator. When the car is not running (but on) the gauge only gets power
> between 1/3 and 1/2 the time (it will see 4 to 6 volts.) When the
> vehicle is running it will get power even less time as the thermal coil
> heats faster (and cooling is limited by the box its in.) With these
> gauges the worst case I could fine was aircooled VW and the resistance
> of the gauge is only 12 ohms (running at about 4 volts, average.) More
> looking may find an even lower resistance gauge in use. To drive the VW
> unit I was looking at would mean about 1.25 amps when on (assuming the
> +12 regulator was on during that pulse - it switches only 2 to 5 times a
> second.) Some newer vehicles still use these gauges because they are
> very good at preventing fuel slosh from causing quick changes in
> reading. They also handle the variable vehicle voltage quite well if
> they use a voltage regulator. Some newer vehicles use this gauge with an
> electronic regulator (not quite sure how they may react to PWM - I may
> be wise to assume that the regulator will be removed and the gauge fed
> strait +12v and looking for your PWM ground.)
>
> Another fuel gauge is the balancing coil gauge. These generally feed the
> auto +12 volts in, where it runs through two coils working in opposite
> directions. Changes in auto system voltage are naturally canceled (to a
> degree) and temperature changes are no longer an issue. A quick look
> shows one (I didn't look as much - I'd like to run a thermal gas gauge)
> where +12v goes to a 62 ohm coil, then a second 155 ohm coil and finally
> ground. The fuel gauge sender was connected between the two coils and
> was 0 to 100 ohms to ground depending on fuel level (0 ohms being full.)
>
> Lastly, some modern autos use a capacitive gauge. Two thin metal plates
> with a ventilated spacer are in the tank. Electronics use the fact that
> the dielectric constant of air and gasoline are quite different. Not
> sure of the drive control, I had a hard time finding detailed
> information about these.
>
> I'm also not sure about some of the modern fuel gauges that hold their
> reading when the vehicle is off. Whatever their design is (a stepper
> motor??) they are increasingly common. The Geo Metro (a common
> conversion) has this type of gauge as does my Toyota Tacoma Pickup
> (another vehicle often converted - but not mine as it only has 12,000
> miles on it!)
>
> Hope this helps,
> Paul "neon" G.
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
Then in the UK where they pay $7 per gallon or Europe at $6 per gallon why
isn't EVeryone buying EV's? I don't understand is electricity also to the
moon?
Mark
----- Original Message -----
From: "Roy LeMeur" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, September 08, 2005 1:37 AM
Subject: Critical Mass
>
> Howdy Folks
>
> I have been saying these two words to the EV industry folks I have been
> talking to all weekend at the EV drags and everyone sorta nods their head
> like... Yeah, that could be coming.
>
> Looking over Bruce Parmenter's recent EVLN posts makes me think it is even
> more here than I thought.
>
> I talk to folks everywhere I go about EVs, not just at work, and the
amount
> of interest has never been higher.
>
> It is not just the cost of fuel (of all types), though the economics of it
> are an undeniably large factor. I believe more folks are understanding
that
> the effects of peak worldwide oil production and the effects of global
> warming are actually upon us. Long term non fossil fuel energy solutions
are
> desperately needed worldwide and folks see EVs charged by cleaner forms of
> energy as a part of it.
>
> When I give them the numbers.... [folks in the USA are less than 5 percent
> of global population using more than 25 percent of the planet's energy
> resources] they seem to be paying more attention now.
>
> Believe it or not, I did think twice before including the following
> paragraph, I simply believe that time is too short to be catering to folks
> that base their attacks on others driven by their own ignorance anymore.
>
> Any of you folks that don't believe in peak oil or global warming driven
by
> human activity, please don't bother, even off-list, you will get no
> arguement from me. This is not political, it is reality. Go learn
something
> and be part of the solution instead of being part of the problem. You know
> who you are. Do the words "environmental wackos" jog any memories?
> That term sounds political to me and I am certain it is very offensive to
> many if not most on this list and no punches will be pulled in the future
on
> folks who use it, get off it or get off this (non political) list.
>
> end rant, flame powered down.
>
> I won't be responding to comments on this post and if the List Gods see
fit
> to toss me off this list for posting it, so be it.
>
> .
>
>
>
>
> Roy LeMeur
> Olympia WA
>
> My Electric Vehicle Pages:
> http://www.angelfire.com/ca4/renewables/evpage.html
>
> Informative Electric Vehicle Links:
> http://www.angelfire.com/ca4/renewables/evlinks.html
>
> EV Parts/Gone Postal Photo Galleries:
> http://www.casadelgato.com/RoyLemeur/page01.htm
>
--- End Message ---
--- Begin Message ---
I was getting ready to ask the same question...
I've done a drawing at
www.ironandwood.org/Batlayout.htm
Basically I have two packs for my 180 V, upper level of 20 T-125's and lower
level of 10 T-125's. The upper level is in a metal, foam insulated box that I
have just built. It has a cold plate system (thanks to Lee Hart for the idea).
There are about 17 ft (I was able to get some orange #2/0 at normal welding
cable prices) of battery connectors, not including the upper to lower
connectors. I'll have an Anderson 350A connector and 2 500A 300VDC fuses, one
between the levels and the other at the positive post in lower level before
going to the 2 - SW 200B (120 v max) contactors in series, then to my 1khv
Zilla.
Are these placed properly? Should the fuses be in another location? The upper
level will slide back over the lower level for access and the power lines will
be in protective covering, as will the ones going under the truck.
Another concern is the Emeter. Before I disconnect the Anderson, I will have to
disconnect the Emeter in proper sequence, then reconnect it again in proper
sequence, and then reprogram it? Or can I just leave it connected to the 12 V
power?
Any criticisms? Suggestions?
Thanks
Rush
Tucson AZ
www.ironandwood.org
--- End Message ---
--- Begin Message ---
Lee Hart wrote:
> On my EV, I placed vertical sheets of "fish paper" between the batteries
> where spacings were tight. This is the thin, phenolic-impregnated grey
> or brown paper you commonly see used as electrical insulation; it is UL
> listed for voltage rating and non-flammability. It adds essentially
> nothing to the battery spacing, yet prevents leakage paths or shorts.
Sounds like cheap insurance.
When I looked up Fish Paper in the McMaster-Carr catalog, I got
8490K21
Electrical Grade Natural Hard Fiber Sheet
.010" Thick, 24" X 39", Fishpaper
Tensile Strength: 21,000 psi machine direction, 10,000 psi cross direction
Impact Strength: 2 ft.-lbs./in.
Coefficient of Friction: 0.16
Dielectric Strength: 400 V/mil
Arc Resistance: 125 seconds.
Material does not carbonize readily when subjected to arcing.
Comparative Tracking Index 600+
Hardness: Rockwell R: 70
Coefficient of Thermal Expansion: 1.1×10-5 in./in./°F
Weather Resistance: Poor.
Processing: Machinability: Can be easily machined.
Forming: Temper (steam or soak) and then dry in the required form.
Welding: Not recommended.
Scratch Resistance: Material resists light scratches.
Chemical Resistance: Material is insoluble in all ordinary solvents and is
unaffected by alcohol, ether, ammonia, turpentine, naphtha, benzine, and
petroleum. Hot oil reduces the moisture content of the material, but this
loss is subsequently regained. Strong acids and bases attack this material.
Lee: Is this what you meant?
--
Mike Bianchi
--- End Message ---
--- Begin Message ---
Hi Seppo and All,
Seppo Lindborg <[EMAIL PROTECTED]> wrote:
>
> Lähettäjä: "David Roden"
>
>
> I can't remember where, but I read once about a fellow who actually DID use
> a long extension cord to run his Elec-Trak!
Hey, that brought back a memory from my childhood.
I was a little kid, some 9-10 years old. I was visiting a construction site
where my dad worked. One caterpillar had blown its motor completely at a
critically scheduled project. While waiting for the replacement motor, my
father had made a temporary fix by taking the motor out and installing a big
3-phase electric motor instead. It was connected with a thick cord to the
electricity distribution cabinet beside the working area. They had also built a
rack and a couple of meters long arm behind the driver to carry the cord and
prevent it from getting under the caterpillar.
Obviously it was not too manouverable, they could work only a small area at a
time and the driver had to keep constant watch for the cord. But it was enough
to limp through that task and keep the overall project going.
Seppo
I until recently mowed my lawn with a corded mower and it was
easier, faster as dealing with an ICE mower
All our Phosphate industry here in Fla use corded drag lines and
they are huge like the size of a 6 story 40 unit apt building and that doesn't
include the crane part. Needless to say the cord was rather large!! EV's are
everywhere!!
Jerry Dycus
>
>
> David Roden - Akron, Ohio, USA
> EV List Assistant Administrator
---------------------------------
Click here to donate to the Hurricane Katrina relief effort.
--- End Message ---
--- Begin Message ---
On Thu, Sep 08, 2005 at 05:35:38PM +0000, damon henry wrote:
> I still don't believe your bus will hold up for 228 years with only 1
> undetected error....
Why not?
If you put a checksum on a packet, it is simple math to determine how strong
the checksum is, and therefore how many packets at what corruption rate will
statistically defeat the sum.
I can believe these numbers will be amazingly huge.
Here is a fun quote from Bruce Schneier on this point:
MD5 is a 128-bit hash; the odds of two texts having identical MD5 hashes are 1
in 2^64. SHA-1 is a 160-bit hash; the odds of two texts having identical SHA-1
hashes are one in 2^80. Assuming the two hash functions are independent -- a
reasonable assumption -- then the odds of two texts having identical MD5 and
SHA-1 hashes are 1 in 2^144.
The universe will either collapse on itself or the galaxies will drift apart
into nothingness before you find such a pair of texts.
So there you go! You just need to build both an MD5 and SHA1 sum into the
protocol, and you will never have an undetected error in the lifetime of the
buss. Then again, it looks like you can already say that ;)
> In fact I bet you will have a hard time pointing out
> to me anything manmade that will work for that much time at all let alone
> error free...
Not quite 228 years, but still pretty amazing.
http://www.energyquest.ca.gov/time_machine/centennial_lightbulb.html
> If it's not for marketing, what's the point of making a
> claim that is so obviously unrealistic.
>
> >From: Victor Tikhonov <[EMAIL PROTECTED]>
> >Reply-To: ev@listproc.sjsu.edu
> >To: ev@listproc.sjsu.edu
> >Subject: Re: Buses talk...
> >Date: Thu, 08 Sep 2005 10:21:38 -0700
> >
> >Lee,
> >
> >It's the same as MTBF failure rate - these things can be calculated
> >and predicted quite accurately. We do it all the time in semiconductor
> >industry to predict life time. It predicts it statistically,
> >specifying acceptable failure rate and probability.
> >
> >In case of the bus errors, the rate can be calculated as well.
> >
> >Note, I said *undetected* error occurs that often. A bus errors
> >occur far more frequently, but are transparent to the user -
> >bad data is ignored and automatically re-transmitted, it is
> >partially built in the silicon and also part of the standard
> >protocol. So application sees no errors.
> >
> >This has nothing to do with marketing.
> >
> >Victor
> >
> >Lee Hart wrote:
> >>>>This is enough because combined with CAN error handling capability
> >>>>the undetected error rate is stunning 1 error per every 1,000 years
> >>>>in a vehicle running 2000 hours/year with 500 kbps bus loaded 25%.
> >>
> >>
> >>damon henry wrote:
> >>
> >>>Ummmm yeah right how did someone come up with this. In a non-leap year
> >>>there are 8760 hours so it would take 228 years to prove this. I don't
> >>>believe the standard has been around quite that long :-)
> >>
> >>
> >>It's basically a guess, based on statistics and a lot of assumptions.
> >>You start by assuming an average bit error rate; say, 1 bad bit per
> >>million. You then assume these bad bits are randomly distributed; i.e.
> >>two bad bits might be anything from right next to each other to two
> >>million bits apart. Then you look at where two bad bits need to be in a
> >>packet to cancel each other out so the packet still appears to be
> >>correct (and so fools the error-detection algorithm).
> >>
> >>It will turn out that there is a short list of places in the packet
> >>where these two bit errors have to occur. You the figure out how long it
> >>will take before the two error bits just happen to land there.
> >>
> >>The trouble is, all this assumes you have perfect knowledge about the
> >>noise source. In reality, noise is unpredictable. So such calculations
> >>are largely useless except as a crude way to compare two different
> >>systems (or for Marketing people to "sell" you on their system).
> >
> >--
> >Victor
> >'91 ACRX - something different
> >
--- End Message ---
--- Begin Message ---
Despite very spread misconseption about closed tailgate of the truck
increasing grag, you will find that keeping it closed will
*reduce* the drag compared to open gate.
I can explain why, but do your careful measurements.
It was great talk about this very issue on KTSA radio in
San Antinio years ago. The drag was measured and closed
gate won, which is very counterintuitive. But one can't
argue with measurable facts. Only ignore them.
Victor
Mark Hastings wrote:
I think tommorow I'm going to drop my tailgate like I see so many
other pickups do. That is where the electric vehicle sign is pretty
much embedded in. I do have two large purple electric cords on the
side that I can't get rid of but maybe they'll think I'm an
electrician.
--- End Message ---
--- Begin Message ---
Do you recall if they tested the difference between a short bed and a longbed
truck.
I know with my shortbox truck (6ft) that keeping the gate up is indeed better.
but I seem to recall that the gate down on the longbed (8ft) was better, but it
probably wasn't.
It seems like it would be really easy to test this on an EV truck.
Stay Charged!
Hump
Original Message -----------------------
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Victor Tikhonov
Sent: Thursday, September 08, 2005 2:54 PM
To: ev@listproc.sjsu.edu
Subject: Closed tailgate of the truck
Despite very spread misconseption about closed tailgate of the truck
increasing grag, you will find that keeping it closed will
*reduce* the drag compared to open gate.
I can explain why, but do your careful measurements.
It was great talk about this very issue on KTSA radio in San Antinio years
ago. The drag was measured and closed gate won, which is very
counterintuitive. But one can't argue with measurable facts. Only ignore
them.
Victor
Mark Hastings wrote:
>
> I think tommorow I'm going to drop my tailgate like I see so many
> other pickups do. That is where the electric vehicle sign is pretty
> much embedded in. I do have two large purple electric cords on the
> side that I can't get rid of but maybe they'll think I'm an
> electrician.
>
--- End Message ---
--- Begin Message ---
what about a bed cover? help or hurt?
db
----- Original Message -----
From: "Victor Tikhonov" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Thursday, September 08, 2005 2:53 PM
Subject: Closed tailgate of the truck
Despite very spread misconseption about closed tailgate of the truck
increasing grag, you will find that keeping it closed will
*reduce* the drag compared to open gate.
I can explain why, but do your careful measurements.
It was great talk about this very issue on KTSA radio in
San Antinio years ago. The drag was measured and closed
gate won, which is very counterintuitive. But one can't
argue with measurable facts. Only ignore them.
Victor
Mark Hastings wrote:
I think tommorow I'm going to drop my tailgate like I see so many
other pickups do. That is where the electric vehicle sign is pretty
much embedded in. I do have two large purple electric cords on the
side that I can't get rid of but maybe they'll think I'm an
electrician.
--- End Message ---
--- Begin Message ---
Mike Barber wrote:
>
> Lee Hart wrote:
>
> >learn the motor's characteristics and adapt to it themselves (I have an
> Aerovironment inverter that does this). Third, even >if you don't match them
> precisely, the inverter should be designed to still work with only a slight
> loss of efficiency and >performamce.
>
> Do you have any specs on that inverter? Sounds pretty neat.
It's an Aerovironment SPC-2000. This inverter is intended for
solar-powered water pumping applications. Basic specs are:
input: 150-600vdc, draws 8 amps max
output: standard 115vac, 208vac, or 230vac 50/60hz induction motor
up to 1.5hp single-phase or 2.5 hp 3-phase
9.5 amps continuous, 13 amps peak
30-69 hz output frequency range
95-97% efficient
There are DIP switches to set the basic motor voltage and type (single
phase or 3-phase). From there, the inverter measures the motor's current
and power factor to determine the load and optimum waveforms.
I'm sure you give up a little efficiency by using self-learned
parameters and a stock 60hz motor. But the cost savings could be worth
it for a hobbyist EV.
--
Every act of conscious learning requires the willingness to suffer an
injury to one's self-esteem. That is why young children, before they
are aware of their own self-importance, learn so easily. - Thomas Szasz
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Mark Hanson wrote:
> So it seems you could only regen at your max speed where the voltage
> would try to exceed the battery voltage.
Not quite. With a PM motor (or shunt motor at fixed field current),
imagine connecting it straight to the battery and letting it run
no-load. It will run at some constant rpm, which corresponds to some
constant road speed (which depends on you gear ratio and tire size).
If the car goes slower than that, it becomes a motor, and draws current
FROM the battery.
If the car goes faster than that, it becomes a generator and CHARGES the
battery.
The higher the efficiency of the motor, the harder it fights to maintain
its no-load speed, and the more current it draws or generates to do so.
If you can change the gearing or field current, you can change the point
at which this happens.
> I wonder how the Curtis regen's to 0 mph
If you mean the stock Curtis controller's "plug braking", it is not
regen; it is shorting the motor and varying the field current to control
how much braking you get. The braking energy is being turned into heat
in the motor and controller, not charging the batteries. But it works
right down to (essentially) zero speed.
If you mean the Curtis 121R regen controller, I *think* it uses the PWM
to drive just the field, and feeds the generated armature voltage thru a
diode to charge the batteries. Otmar might know for sure. Otmar?
--
Every act of conscious learning requires the willingness to suffer an
injury to one's self-esteem. That is why young children, before they
are aware of their own self-importance, learn so easily. - Thomas Szasz
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Lee,
Reason for the good prices I quoted is that these are the
distributer volume prices of UB. I will be buying straight
from the manufacturer.
I still have a question outstanding about more specs and
charging recommendation.
Of course I also want to do my own test, so I borrowed two
new UB121100 that were never recharged and started cycling
first one, then the other in the past days.
I charged the first with a lab supply set to 10A max, 14.9V max
according the max voltage value in the spec (15V) and I loaded
the battery with 75A until voltage drops to 10.5 and measure
the time to calculate the capacity.
I saw that the first battery quickly lost capacity when it was
kept a few hours at 14.9V (mild gassing could be heard inside
the battery). I saw the capacity drop almost 20Ah over 5 cycles.
So I decided to test the 2nd battery with a charging voltage
no higher than 14.1V (the lowest recommended voltage in the spec)
and after only 3 cycles it is hard to draw a conclusion but the
capacity is constant at 75Ah, I will make at least 10 cycles to
see if the capacity will "grow" as it is supposed to in the
break-in period.
Will keep you updated,
Cor van de Water
Systems Architect
Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [EMAIL PROTECTED]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3673 eFAX: +31-84-717-9972
Proxim Wireless Networks eFAX: +1-501-641-8576
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Lee Hart
Sent: Friday, September 02, 2005 6:33 PM
To: ev@listproc.sjsu.edu
Subject: Re: Even better price for AGM, was: Best Flooded Battery
Cor van de Water wrote:
> Anybody interested in AGM (sealed lead acid) batteries for the price
> of Flooded cells? I contacted Universal Battery directly (located
> in Texas) and since they have no representative in the SF Bay Area,
> they can ship directly if the quantity is acceptably large.
My grandpa used to say, "If a deal looks too good to believe, don't
belive it!" His advice has served me well many times. I would be very
careful.
Any serious battery manufacturer should have BCI test data, which will
tell you how it performs according to a standardized set of tests. Ask
for this data. It will include amphour capacity at various currents,
internal resistance at various temperature, and cycle life at a
specified current and depth of discharge.
I would also order an extra 10% or so batteries. You should expect that
there will be "turkeys" that aren't bad enough to send back under
warranty, but are clearly substandard compared to the rest. If you get
lucky and they are all good, keep the spares as future replacements.
If you're buying from someone in the US, use your credit card. If they
fail to ship or ship junk, you have at least some recourse to get your
money back.
--
*BE* the change that you wish to see in the world.
-- Mahatma Gandhi
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
:o/
"Strong acids and bases attack this material"
----- Original Message -----
From: "M Bianchi" <[EMAIL PROTECTED]>
To: <EV@listproc.sjsu.edu>; <[EMAIL PROTECTED]>
Sent: Thursday, September 08, 2005 1:30 PM
Subject: Re: Re Hep with battery wiring, avoid looping back
Lee Hart wrote:
On my EV, I placed vertical sheets of "fish paper" between the batteries
where spacings were tight. This is the thin, phenolic-impregnated grey
or brown paper you commonly see used as electrical insulation; it is UL
listed for voltage rating and non-flammability. It adds essentially
nothing to the battery spacing, yet prevents leakage paths or shorts.
Sounds like cheap insurance.
When I looked up Fish Paper in the McMaster-Carr catalog, I got
8490K21
Electrical Grade Natural Hard Fiber Sheet
.010" Thick, 24" X 39", Fishpaper
Tensile Strength: 21,000 psi machine direction, 10,000 psi cross
direction
Impact Strength: 2 ft.-lbs./in.
Coefficient of Friction: 0.16
Dielectric Strength: 400 V/mil
Arc Resistance: 125 seconds.
Material does not carbonize readily when subjected to arcing.
Comparative Tracking Index 600+
Hardness: Rockwell R: 70
Coefficient of Thermal Expansion: 1.1×10-5 in./in./°F
Weather Resistance: Poor.
Processing: Machinability: Can be easily machined.
Forming: Temper (steam or soak) and then dry in the required
form.
Welding: Not recommended.
Scratch Resistance: Material resists light scratches.
Chemical Resistance: Material is insoluble in all ordinary solvents and is
unaffected by alcohol, ether, ammonia, turpentine, naphtha, benzine,
and
petroleum. Hot oil reduces the moisture content of the material, but
this
loss is subsequently regained. Strong acids and bases attack this
material.
Lee: Is this what you meant?
--
Mike Bianchi
--- End Message ---
--- Begin Message ---
Why not... easy I don't believe the material that forms the bus will be
useable in 228 years. You show me one piece of electronics that is still
functional from 228 years ago and then I'll believe :-) That's what makes
this claim ridiculous, not that the theory is wrong or even tough to
understand, just that the implemtation trumps the theory. Either these
numbers were made up by someone in marketing, or someone has been
engineering in a vacuum again. Besides why say 1 error in 1000 years, why
not just say error free over the lifetime. Surely if you can claim only one
undetected error over an unrealistic timeframe it is no more of a stretch to
claim error free.
From: Nick Austin <[EMAIL PROTECTED]>
Reply-To: ev@listproc.sjsu.edu
To: ev@listproc.sjsu.edu
Subject: Re: Buses talk...
Date: Thu, 8 Sep 2005 11:45:31 -0700
On Thu, Sep 08, 2005 at 05:35:38PM +0000, damon henry wrote:
> I still don't believe your bus will hold up for 228 years with only 1
> undetected error....
Why not?
If you put a checksum on a packet, it is simple math to determine how
strong
the checksum is, and therefore how many packets at what corruption rate
will
statistically defeat the sum.
I can believe these numbers will be amazingly huge.
Here is a fun quote from Bruce Schneier on this point:
MD5 is a 128-bit hash; the odds of two texts having identical MD5 hashes
are 1
in 2^64. SHA-1 is a 160-bit hash; the odds of two texts having identical
SHA-1
hashes are one in 2^80. Assuming the two hash functions are independent --
a
reasonable assumption -- then the odds of two texts having identical MD5
and
SHA-1 hashes are 1 in 2^144.
The universe will either collapse on itself or the galaxies will drift
apart
into nothingness before you find such a pair of texts.
So there you go! You just need to build both an MD5 and SHA1 sum into the
protocol, and you will never have an undetected error in the lifetime of
the
buss. Then again, it looks like you can already say that ;)
> In fact I bet you will have a hard time pointing out
> to me anything manmade that will work for that much time at all let
alone
> error free...
Not quite 228 years, but still pretty amazing.
http://www.energyquest.ca.gov/time_machine/centennial_lightbulb.html
> If it's not for marketing, what's the point of making a
> claim that is so obviously unrealistic.
>
> >From: Victor Tikhonov <[EMAIL PROTECTED]>
> >Reply-To: ev@listproc.sjsu.edu
> >To: ev@listproc.sjsu.edu
> >Subject: Re: Buses talk...
> >Date: Thu, 08 Sep 2005 10:21:38 -0700
> >
> >Lee,
> >
> >It's the same as MTBF failure rate - these things can be calculated
> >and predicted quite accurately. We do it all the time in semiconductor
> >industry to predict life time. It predicts it statistically,
> >specifying acceptable failure rate and probability.
> >
> >In case of the bus errors, the rate can be calculated as well.
> >
> >Note, I said *undetected* error occurs that often. A bus errors
> >occur far more frequently, but are transparent to the user -
> >bad data is ignored and automatically re-transmitted, it is
> >partially built in the silicon and also part of the standard
> >protocol. So application sees no errors.
> >
> >This has nothing to do with marketing.
> >
> >Victor
> >
> >Lee Hart wrote:
> >>>>This is enough because combined with CAN error handling capability
> >>>>the undetected error rate is stunning 1 error per every 1,000 years
> >>>>in a vehicle running 2000 hours/year with 500 kbps bus loaded 25%.
> >>
> >>
> >>damon henry wrote:
> >>
> >>>Ummmm yeah right how did someone come up with this. In a non-leap
year
> >>>there are 8760 hours so it would take 228 years to prove this. I
don't
> >>>believe the standard has been around quite that long :-)
> >>
> >>
> >>It's basically a guess, based on statistics and a lot of assumptions.
> >>You start by assuming an average bit error rate; say, 1 bad bit per
> >>million. You then assume these bad bits are randomly distributed; i.e.
> >>two bad bits might be anything from right next to each other to two
> >>million bits apart. Then you look at where two bad bits need to be in
a
> >>packet to cancel each other out so the packet still appears to be
> >>correct (and so fools the error-detection algorithm).
> >>
> >>It will turn out that there is a short list of places in the packet
> >>where these two bit errors have to occur. You the figure out how long
it
> >>will take before the two error bits just happen to land there.
> >>
> >>The trouble is, all this assumes you have perfect knowledge about the
> >>noise source. In reality, noise is unpredictable. So such calculations
> >>are largely useless except as a crude way to compare two different
> >>systems (or for Marketing people to "sell" you on their system).
> >
> >--
> >Victor
> >'91 ACRX - something different
> >
--- End Message ---
--- Begin Message ---
Look at the last line. " Strong acids and bases attack this material." is this
what you want near your batteries?
M Bianchi <[EMAIL PROTECTED]> wrote:Lee Hart wrote:
> On my EV, I placed vertical sheets of "fish paper" between the batteries
> where spacings were tight. This is the thin, phenolic-impregnated grey
> or brown paper you commonly see used as electrical insulation; it is UL
> listed for voltage rating and non-flammability. It adds essentially
> nothing to the battery spacing, yet prevents leakage paths or shorts.
Sounds like cheap insurance.
When I looked up Fish Paper in the McMaster-Carr catalog, I got
8490K21
Electrical Grade Natural Hard Fiber Sheet
.010" Thick, 24" X 39", Fishpaper
Tensile Strength: 21,000 psi machine direction, 10,000 psi cross direction
Impact Strength: 2 ft.-lbs./in.
Coefficient of Friction: 0.16
Dielectric Strength: 400 V/mil
Arc Resistance: 125 seconds.
Material does not carbonize readily when subjected to arcing.
Comparative Tracking Index 600+
Hardness: Rockwell R: 70
Coefficient of Thermal Expansion: 1.1×10-5 in./in./°F
Weather Resistance: Poor.
Processing: Machinability: Can be easily machined.
Forming: Temper (steam or soak) and then dry in the required form.
Welding: Not recommended.
Scratch Resistance: Material resists light scratches.
Chemical Resistance: Material is insoluble in all ordinary solvents and is
unaffected by alcohol, ether, ammonia, turpentine, naphtha, benzine, and
petroleum. Hot oil reduces the moisture content of the material, but this
loss is subsequently regained. Strong acids and bases attack this material.
Lee: Is this what you meant?
--
Mike Bianchi
--- End Message ---
--- Begin Message ---
Here is a good explanation... http://www.awtrucks.com/tailgateup.htm
Snip>>>>>>>>
I'm an aerodynamics engineer. When I was in the U.S. Air Force a few
years back, I worked with folks from the Lockheed low-speed wind tunnel.
In the 1970s aircraft production went into a slump, and Lockheed started
looking.for other customers for its wind-tunnel services.
Prime candidates were automakers, and Lockheed was successful in
convincing Ford, among others, that the wind tunnel wouId help them
reduce drag and wind noise on their vehicles.
Needless to say, in the past 15 to 20 years, Lockheed has learned a lot
about car and truck aerodynamics.
Anyway, they actually performed drag tests on pickups with the tailgate
both up and down, and found that drag was actually LOWER with the
tailgate CLOSED!
This ran counter to their intuition (and yours). The reason is that a
closed tailgate sets up a large "bubble" of stagnant air that slowly
circulates around the bed of the truck (we aero types call this a
("separated bubble"). When air approaches the truck, it "sees" the
bubble as part of the truck. So to the air, the truck looks like it has
a nice, flat covering over the bed, and the air doesn't "slam" into the
vertical tailgate.
If the tailgate is open, or replaced by one of those "air gate" nets,
however, that nice, separate bubble in the truck bed does not form (it
"bursts").
Then the air approaching the truck "sees" a truck with a flat bed on the
back of a tall cab. This is a very nonaerodynamc shape with a very LARGE
drag.
So, believe it or not, it's best for gas mileage to keep the tailgate
CLOSED. Hope this information is helpful.
Ed Fitzgerald
Research Assistant
Department of Aero/Mechanical Engineering
University of Notre Dame
Snip>>>>>>>>>>>
---------------------------------------------------------------------
Jay Brown
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Tim Humphrey
Sent: Thursday, September 08, 2005 2:01 PM
To: ev@listproc.sjsu.edu
Subject: RE: Closed tailgate of the truck
Do you recall if they tested the difference between a short bed and a
longbed truck.
I know with my shortbox truck (6ft) that keeping the gate up is indeed
better. but I seem to recall that the gate down on the longbed (8ft) was
better, but it probably wasn't.
It seems like it would be really easy to test this on an EV truck.
Stay Charged!
Hump
Original Message -----------------------
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Victor Tikhonov
Sent: Thursday, September 08, 2005 2:54 PM
To: ev@listproc.sjsu.edu
Subject: Closed tailgate of the truck
Despite very spread misconseption about closed tailgate of the truck
increasing grag, you will find that keeping it closed will
*reduce* the drag compared to open gate.
I can explain why, but do your careful measurements.
It was great talk about this very issue on KTSA radio in San Antinio
years
ago. The drag was measured and closed gate won, which is very
counterintuitive. But one can't argue with measurable facts. Only ignore
them.
Victor
Mark Hastings wrote:
>
> I think tommorow I'm going to drop my tailgate like I see so many
> other pickups do. That is where the electric vehicle sign is pretty
> much embedded in. I do have two large purple electric cords on the
> side that I can't get rid of but maybe they'll think I'm an
> electrician.
>
--- End Message ---
