EV Digest 5949
Topics covered in this issue include:
1) RE: Build EV For Someone Else
by Cor van de Water <[EMAIL PROTECTED]>
2) RE: Hope for EV's
by Cor van de Water <[EMAIL PROTECTED]>
3) Re: emeter power supply nte1212
by Lee Hart <[EMAIL PROTECTED]>
4) Zilla controls backordered?
by "Michael Trefry" <[EMAIL PROTECTED]>
5) Re: Charging Woes
by TiM M <[EMAIL PROTECTED]>
6) Battery boxes
by "Michael Trefry" <[EMAIL PROTECTED]>
7) RE: Ranger doner
by "Roger Stockton" <[EMAIL PROTECTED]>
8) Re: Motor size questions
by "Peter VanDerWal" <[EMAIL PROTECTED]>
9) RE: Zilla controls backordered?
by Cor van de Water <[EMAIL PROTECTED]>
10) Re: Motor size questions
by Scott Serr <[EMAIL PROTECTED]>
11) Re: Motor size questions
by David Dymaxion <[EMAIL PROTECTED]>
12) RE: Floodies/Batt. murder mystery/Thanks to Roger & Roland
by "Roger Stockton" <[EMAIL PROTECTED]>
13) Tailgate effects, was Re: Ranger donor
by [EMAIL PROTECTED]
14) Re: WKTEC flyers
by Peter Eckhoff <[EMAIL PROTECTED]>
15) RE: Charging Woes
by Cor van de Water <[EMAIL PROTECTED]>
16) RE: Ranger doner
by Cor van de Water <[EMAIL PROTECTED]>
--- Begin Message ---
Curtis,
Indeed - as I said: a space frame, unique design.
http://www.madkatz.com/acpropulsion/tzero.html
It is not impossible per se, just a matter of how deep
your pockets are. It makes sense if you want build
at least several hundreds, if not thousands of these
vehicles, otherwise you won't recoup the money, as not
many people can afford close to a million dollars, let
alone that they want to pay more than for the Tesla.
The other end of the range is when you are a hobbyist
with lots of spare time and you like to weld and like
to deal with the organisation that determines the safety
of your car in your state.
I, for one, prefer to select a vehicle I like and then
convert it into electric and try to stay under $10,000
so that is why I bought a clean BMW with blown engine
for $1650 last year. Since then I could buy an electric
truck while at the same time I saw that I had not enough
time to convert the BMW. So I fixed the engine and sold it.
Your situation may be different.
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 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-610-423-5743
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Curtis Muhlestein
Sent: Sunday, October 01, 2006 7:20 PM
To: [email protected]
Subject: RE: Build EV For Someone Else
Check this out...
http://www.acpropulsion.com/ACP_PDFs/EAASV_101803.pdf#search=%22acpropulsion
%2C%22lead%20acid%22%22
--- End Message ---
--- Begin Message ---
Hi Jeff,
That is exactly what Lee said -
teach the kids, their minds are not so closed yet.
Success,
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 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-610-423-5743
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Jeff Shanab
Sent: Sunday, October 01, 2006 6:42 PM
To: Electric Vehicle Discussion List
Subject: Hope for EV's
I went to the laundry mat like I have done each sunday since my dryer
broke and a girl there made my day. It started as an explination of why
to go to school (cause I had books with me and she asked) and I
mentioned that school allowed me to get a better job and convert the car
to electric and do other fun things. After the initial disbelief of not
using gas, she asked how I got the cord to stretch so far. Surprised she
new what I meant by electric, I explained it had batteries like a cell
phone or toy car and I just plug it in each night.
Her response: "I want one"
I promised by the time she was old enough to drive, there would be
electric cars for her. I have about 10 years to make good on that
promise, little Venessa is only 6 years old.
I guess our primary mission is to drive everyday and lead by example.
--- End Message ---
--- Begin Message ---
mike golub wrote:
what if the nte1212 takes the power from the iota when
used as a 120vdc to 12dc converter?
The fundamental problem is that the Link-10/E-meter's negative power
supply is connected DIRECTLY to your propulsion pack negative. So,
whatever you use to power the Link-10/E-meter has its negative 12v
output connected DIRECTLY to the propulsion pack!
Here's the worst-case scenario. Suppose you use a non-isolated charger.
Then your propulsion pack is connected to the AC power line (through a
bridge rectifier). The AC power line routinely has >1000v voltage
spikes. These will all appear on your propulsion pack, too.
The negative of an automobile's 12v system is grounded to the chassis.
If you power the E-meter directly from your 12v accessory battery, you
have a DIRECT SHORT from the AC power line to ground! ZAP!
If you use something like the NTE1212 to power the Link-10/E-meter from
the 12v system, then it works only until the NTE1212's input/output
isolation breaks down. When it does, you'll have the same short circuit,
same deadly shock hazard, and same chance of a fire as if there were no
isolation to begin with.
I guess those laptop powers supplies is the way to go?
That is a lot safer, because they are normally built to survive those
>1000 volt spikes on the AC line. A laptop power supply could be
powered from your propulsion pack, and have its output power the
E-meter. But, be SURE that the supply's negative output is NOT connected
to the AC input's ground (green) wire!
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
So I've decided to go DC to allow the maximum flexibility of tweaking and
tuning.
BUT .
I just visited the Zilla web-site, and it looks like the controllers are
backordered over 6 months.
What are the chances of finding a used Zilla, and would I want to?
Are there any other controllers AS good for the EV hobbyist?
--- End Message ---
--- Begin Message ---
OK, I found the problem. After a hard run, ~70%
discharged, and checked individual voltages. I found
one that read 3.7V while all the rest were reading
between 6.09 and 6.11. So it looks like I have a dead
cell in my pack. I'm surprised this didn't show up
with the lighter ~30 discharge cycle.
Will it hurt anything if I continue to drive
light cycles with the bad battery? Would it be better
to remove the stinker and jumper it until I get the
replacement? How bad is it going to be to put one new
battery in with the ~14 month old pack? What other
option do I have? I'm hoping the one dead battery is
an anomaly, I was hoping to get 4 or more years out of
this pack.
TiM
__________________________________________________
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Tired of spam? Yahoo! Mail has the best spam protection around
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--- End Message ---
--- Begin Message ---
What are the function of battery boxes/racks other than holding the
batteries in place? Why would a box cost over $2000? (box and rack set for
914 at electroauto.com)
I've seen sites mention making these from steel, aluminum, even wood. Why
not plastic or fiberglass to reduce weight?
Thanks,
Mike Trefry
--- End Message ---
--- Begin Message ---
Rush wrote:
> Yes I have had stock tailgates, but in any case I wasn't
> talking about *me*, I was referring to *other full timers*
I understood this; I just wondered if you had actually measured and
difference/improvement since you had the means available, or if you had
just accepted the other full-timers' anecdotal claims.
> I wouldn't be too *sure* about that Roger... lots of those
> old timers are retired machinists, electricans, engineers
> etc, who are used to being able to *prove* what they say. I'm
> sure that some of them have logs with orders of precision to
> the hundredths... They love to discuss how many mpg they get
> with a headwind and with a tailwind, going down a hill and up
> a hill. They have lots of experience as a collective whole.
Great! Did any of them share any data with you *quantifying* the
difference between a stock tailgate and a vented one *without* a 5th
wheel attached?
> > It is entirely possible that the open tailgate mileage is
> > *worse* than either of the alternatives.
>
> And the opposite is true also, it is entirely possible that
> the open tailgate milage is *better* that the alternative.
> Many things are *possible* Grasshopper... <G>
Well said! ;^>
> Roger, what do mesh/screen tailgate/loading ramps have to do
> with tailgates?
Just that one should not assume that just because one can largely see
through something it will offer no resistance to the passage of air,
especially at highway speeds.
Obviously, the mesh tailgate/loading ramp on a trailer is about 3-4x the
crossectional area as a tailgate, so the effect will be much more
apparent, however, the mesh truck tailgate will also exhibit resistance
to airflow that an open tailgate will not.
The suggestion here is that the aerodynamics will be different; a mesh
tailgate will exhibit *some* resistance to airflow and so while air may
pass through it, the air will slow somewhat and slower/still air may
accumulate in front of the tailgate, similar to what might happen with a
solid tailgate, though perhaps to a lesser degree.
> As usual the thread has veered off in another direction, they
> have a tendancy to do that <G>. But the intent is there, to
> give *evidence*, however unreliable you may deem it to be
> that either supports or does not support your *assumption*.
The only issue I have is that (with the notable exception of Lynn's
recent post) the *evidence* offered has either been unsubtantiated
opinion or anecdotal in nature. This is fine for those who are
satisfied with such, but I'm the sort that requires *quantitative* data
to be convinced one way or the other. (And I'm not asking for anyone to
convince me, I'm just observing that *if* quantitative data were offered
I would find it more convincing ;^)
> If you are pissed that the thread is not following your
> direction, then that is another matter..
Naa, I don't particularly care where the thread goes; I just wanted to
make sure that people were aware that the tailgate thing was only
mentioned as an example of why one should seek *quantitative* proof that
something results in an efficiency improvement rather than assuming that
it will.
I don't *know* which tailgate option is most efficient (or if a flatdeck
is more efficient than a stock box), because I haven't measured it for
myself. However, the Mythbusters episode (however imperfect) provides
sufficient evidence for me that should I convert a pickup, I will
certainly measure the various tailgate options rather than assuming the
open tailgate is better.
> It's not that you are not trusted Roger, you have contributed
> a great deal of your knowledge and we respect your words.
Thanks for the kind words, however, in this case there really is no
reason to trust me! I haven't claimed *anything* (open/closed/vented
tailgate or flatdeck/stock box) is more efficient than something else;
all I've done is offer reasons illustrating why it is important to
question one's assumptions and evaluate the options for oneself.
> But others also have experiences and knowledge and have the
> right to express it without being told that we are sticking
> our heads in the sand...
My 'head-in-the-sand' comment was really made with Joe Strubner (sp?) in
mind, not yourself or others in this thread.
I really am hoping that if this thread doesn't just die off, *someone*
will offer up some nice hard data showing which option ws measurably
more efficient for them.
So far we've just had a couple people saying they either do or don't
believe the Mythbusters result that the closed tailgate is more
efficient, yourself reporting that 'full timers' believe their 5th wheel
vented/mesh tailgates result in improved mileage (but no indication if
this is with or without the 5th wheel attached, nor is any quantitative
data offered and you don't seem to have measured to see if your own
tailgate results in an improvement for you or not), one person
suggesting that racers have found the tailgate up to be more efficient
at high speeds, and Lynn reporting quantitative data supporting his
assertion that a partial tonneau cover improves the efficency of his
E10.
Even though some are questioning if Lynn's data is the best it could
possibly be, what speaks volumes to me is that GM originally fitted an
unusual partial tonneau cover to the vehicle. Clearly *they* believed
this was an improvement over the open box, and, one would suspect, over
an open box without tailgate. Since the partial tonneau cover is an
unusual item, and represents additional cost, I expect GM engineers
measured enough of an improvement with this arangement to justify it to
the bean counters.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
> I too have the "motor size question." I'm trying to summarize the great
> details (here and in the other replies) into something I can easily
> digest at this point. :)
>
> It sounds like going from a 9" motor to a 11" motor has no inherent
> downside on range. What really matters is if you are running a motor
> (any motor) in it's efficient RPM range. There is no inherent loss in
> efficiency with a larger motor.
That's not quite right. If you use too large a motor, then the amount of
power you need ends up being so far down on the curve that you run in the
low efficiency zone for that motor.
However, using an 11" warp when all you need is a 9" ADC (or warp)
probably won't have a significant effect on your range, just your wallet.
Of course, depending on your application, it might not have any
significant advantage either.
>
> Am I on track? From a 60 mile endurance point of view... with a
> continuous load.
>
> Thanks,
> Scott
>
> On 10/01/06 22:01, Peter VanDerWal wrote:
>>> does a larger motor, in general, use more, same, or less energy to
>>> produce the same torque? power? for example, given my car requires X
>>> units of power to travel at 65MPH, how much battery energy (relativity)
>>> would a 8", 9", or 11" motor drain for the same time period.
>>>
>>
>> You are mixing units. How much energy does it take to make 100 HP?
>> Sort
>> of like asking how many gallons of water are in 80 psi, or how many
>> inches
>> in 100mph?
>>
>> Power = Torque * RPM
>> Energy = Power * Time
>> So Energy = Torque * RPM * Time.
>>
>> So there is no real way to answer the question, as asked.
>>
>> You could have two identically sized motors that produce vastly
>> different
>> torque when fed the same power.
>> I.e One might produce 100 ft-lbs of torque at 5,000 rpm, and the other
>> produce 500 ft-lbs of torque at 1,000 rpm. The same power output, but
>> way
>> different torque.
>>
>>
>> Larger motors generally can produce a given amount of power for a longer
>> period before overheating.
>> How efficient a motor is depends mostly on how well it is constructed.
>> Larger motors are easier to make more efficient than smaller ones
>> because
>> they are larger which means you can get the same relative precision with
>> larger tolerances.
>>
>> There is also a limit to how much power a given motor can produce for
>> even
>> a short period of time without self destructing. I.e there is no way to
>> get 100 HP out of a slot car motor, if you tried to push that much power
>> through it, it would vaporize.
>>
>>
>>> put
>>> another way, how does increasing motor size effect range for a
>>> particular car?
>>>
>>
>> Depends on the motor, not the size. They make 8" motors that are more
>> efficient than 11" motors.
>> It also dpends on the application.
>>
>> You'd need to compare the efficiency of the motors are a given power
>> level. If you look at the torque chart of a given motor, it's
>> efficiency
>> will start at 0% at zero rpm, and increase as the RPMs increase until
>> you
>> hit the maximum efficiency point, and then the efficiency will drop off.
>> But the curve changes at different applied voltages/currents.
>> So you'll most likely hit the maximum efficiency point on a 8" ADC at a
>> lower power level than you will on a 9" ADC. If all you need is this
>> lower power point, then the 8" might be more efficient for you.
>>
>> As an extreem example an 11" motor strapped to a bicycle will be WAY
>> less
>> efficient than a 3" motor designed for bicycles. The 11" motor will
>> draw
>> more power to just idle than the 3" motor will while propelling the
>> bike.
>>
>>
>>> what about highway vs stop-and-go? is motor size even
>>> an apples-to-apples comparison given that i'll likely need different
>>> components to drive different motor? sorry for not being able to ask
>>> questions using better language.
>>>
>>> in reality an 8" or 9" motor will likely produce enough torque for me
>>> to
>>> putt along my short commute to work. but say i want to shift less or
>>> not at all; why not buy an 11" motor, say the Warp 11 or something.
>>> hope that jumble of words makes sense :)
>>>
>>
>> Well, in that case the 11" motor will be less efficient. Shifting down
>> at
>> low speeds allows you to keep the motor spinning up near it's maximum
>> efficiency point. By driving a fixed gear, whenever you are driving
>> slow
>> (or at the slow speed part of accelerating) the motor is in it's low
>> efficiency zone, so even if the motor is more efficient when at it's
>> maximum efficiency point, you are spending more time in it's low
>> efficiency RPMs so seeing lower overall efficiency.
>>
>>
>>
>>> mike
>>>
>>> ps. if this has been covered before, i would gladly accept a link to
>>> some information rather a lengthy reply.
>>>
>>>
>>>
>>
>>
>>
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
--- End Message ---
--- Begin Message ---
I doubt that there are many 'used' Zilla's up for sale, as
they are getting the status of unobtanium, although you can
find them regularly already built-into a used EV, like Steve
Condie's truck that sold for $5k last week.
Mostly the Zilla's are used for racing and for very heavy
vehicles as not many EVs require 1000A motor current.
There are used and refurbished Curtis controllers, Raptor and
some others come to mind. The cool thing of the new EVAlbum is
that you can search on parameters, such as for example controllers.
Of the 859 entries (including bikes and scooters) there are
252 Curtis controllers
71 DC Power Systems (Raptor)
36 Alltrax (golf cart type 36 - 72V)
35 Cafe Electric (Zilla)
35 Auburn Scientific (Kodiak)
24 GE
16 Zapi (H2/H3)
15 4QD
15 Siemens (AC)
When you are on a vehicle page, you can click on the controller
to go to a page about this particular manufacturer's controllers.
Such as
Curtis
http://www.austinev.org/evalbum/curtis
DCP's Raptor
http://www.austinev.org/evalbum/dcp
Cafe Electric's Zilla
http://www.cafeelectric.com/
Auburn's Kodiak and Grizzly
http://www.austinev.org/evalbum/auburn
Zapi
http://www.austinev.org/evalbum/zapi
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 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-610-423-5743
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Michael Trefry
Sent: Sunday, October 01, 2006 10:16 PM
To: [email protected]
Subject: Zilla controls backordered?
So I've decided to go DC to allow the maximum flexibility of tweaking and
tuning.
BUT .
I just visited the Zilla web-site, and it looks like the controllers are
backordered over 6 months.
What are the chances of finding a used Zilla, and would I want to?
Are there any other controllers AS good for the EV hobbyist?
--- End Message ---
--- Begin Message ---
On 10/01/06 23:38, Peter VanDerWal wrote:
>> I too have the "motor size question." I'm trying to summarize the great
>> details (here and in the other replies) into something I can easily
>> digest at this point. :)
>>
>> It sounds like going from a 9" motor to a 11" motor has no inherent
>> downside on range. What really matters is if you are running a motor
>> (any motor) in it's efficient RPM range. There is no inherent loss in
>> efficiency with a larger motor.
>>
>
> That's not quite right. If you use too large a motor, then the amount of
> power you need ends up being so far down on the curve that you run in the
> low efficiency zone for that motor.
>
When you say curve here, you are saying (electrical) power curve not RPM
curve... right?
If thats the case it's a bit like an ICE... with a 5.0L using more gas
to go down the highway than a 3.0L.
?
Thanks, (sorry for beating this to death)
Scott
> However, using an 11" warp when all you need is a 9" ADC (or warp)
> probably won't have a significant effect on your range, just your wallet.
> Of course, depending on your application, it might not have any
> significant advantage either.
>
>
>> Am I on track? From a 60 mile endurance point of view... with a
>> continuous load.
>>
>> Thanks,
>> Scott
>>
>> On 10/01/06 22:01, Peter VanDerWal wrote:
>>
>>>> does a larger motor, in general, use more, same, or less energy to
>>>> produce the same torque? power? for example, given my car requires X
>>>> units of power to travel at 65MPH, how much battery energy (relativity)
>>>> would a 8", 9", or 11" motor drain for the same time period.
>>>>
>>>>
>>> You are mixing units. How much energy does it take to make 100 HP?
>>> Sort
>>> of like asking how many gallons of water are in 80 psi, or how many
>>> inches
>>> in 100mph?
>>>
>>> Power = Torque * RPM
>>> Energy = Power * Time
>>> So Energy = Torque * RPM * Time.
>>>
>>> So there is no real way to answer the question, as asked.
>>>
>>> You could have two identically sized motors that produce vastly
>>> different
>>> torque when fed the same power.
>>> I.e One might produce 100 ft-lbs of torque at 5,000 rpm, and the other
>>> produce 500 ft-lbs of torque at 1,000 rpm. The same power output, but
>>> way
>>> different torque.
>>>
>>>
>>> Larger motors generally can produce a given amount of power for a longer
>>> period before overheating.
>>> How efficient a motor is depends mostly on how well it is constructed.
>>> Larger motors are easier to make more efficient than smaller ones
>>> because
>>> they are larger which means you can get the same relative precision with
>>> larger tolerances.
>>>
>>> There is also a limit to how much power a given motor can produce for
>>> even
>>> a short period of time without self destructing. I.e there is no way to
>>> get 100 HP out of a slot car motor, if you tried to push that much power
>>> through it, it would vaporize.
>>>
>>>
>>>
>>>> put
>>>> another way, how does increasing motor size effect range for a
>>>> particular car?
>>>>
>>>>
>>> Depends on the motor, not the size. They make 8" motors that are more
>>> efficient than 11" motors.
>>> It also dpends on the application.
>>>
>>> You'd need to compare the efficiency of the motors are a given power
>>> level. If you look at the torque chart of a given motor, it's
>>> efficiency
>>> will start at 0% at zero rpm, and increase as the RPMs increase until
>>> you
>>> hit the maximum efficiency point, and then the efficiency will drop off.
>>> But the curve changes at different applied voltages/currents.
>>> So you'll most likely hit the maximum efficiency point on a 8" ADC at a
>>> lower power level than you will on a 9" ADC. If all you need is this
>>> lower power point, then the 8" might be more efficient for you.
>>>
>>> As an extreem example an 11" motor strapped to a bicycle will be WAY
>>> less
>>> efficient than a 3" motor designed for bicycles. The 11" motor will
>>> draw
>>> more power to just idle than the 3" motor will while propelling the
>>> bike.
>>>
>>>
>>>
>>>> what about highway vs stop-and-go? is motor size even
>>>> an apples-to-apples comparison given that i'll likely need different
>>>> components to drive different motor? sorry for not being able to ask
>>>> questions using better language.
>>>>
>>>> in reality an 8" or 9" motor will likely produce enough torque for me
>>>> to
>>>> putt along my short commute to work. but say i want to shift less or
>>>> not at all; why not buy an 11" motor, say the Warp 11 or something.
>>>> hope that jumble of words makes sense :)
>>>>
>>>>
>>> Well, in that case the 11" motor will be less efficient. Shifting down
>>> at
>>> low speeds allows you to keep the motor spinning up near it's maximum
>>> efficiency point. By driving a fixed gear, whenever you are driving
>>> slow
>>> (or at the slow speed part of accelerating) the motor is in it's low
>>> efficiency zone, so even if the motor is more efficient when at it's
>>> maximum efficiency point, you are spending more time in it's low
>>> efficiency RPMs so seeing lower overall efficiency.
>>>
>>>
>>>
>>>
>>>> mike
>>>>
>>>> ps. if this has been covered before, i would gladly accept a link to
>>>> some information rather a lengthy reply.
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>
>
>
>
--- End Message ---
--- Begin Message ---
The extra 50 pounds or so of the bigger motor would displace a
battery, or be an extra 1% to 2% more weight for the vehicle.
So if you have to lose a battery to free up weight for the motor,
sounds like the smaller motor wins (provided it is still big enough
for the job). If the number of batteries remains the same, and the
bigger motor is 2% or more more efficient, then the bigger motor wins
in city driving. If you do mostly high speed driving, then the better
efficiency of the bigger motor probably makes it the winner.
--- Scott Serr <[EMAIL PROTECTED]> wrote:
> ...
> It sounds like going from a 9" motor to a 11" motor has no inherent
> downside on range. What really matters is if you are running a
> motor
> (any motor) in it's efficient RPM range. There is no inherent loss
> in efficiency with a larger motor. ...
__________________________________________________
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--- End Message ---
--- Begin Message ---
Chuck Hursch wrote:
> Those USBMC recommendations appear to
> be IU, no final constant I mentioned. I settled on 5.5A constant
> I. The Zivan K2 (that I have) is an IUI charger, final I for a
> non-adjustable 3 hours.
What you might use as a sanity check is that typically you want to
return between about 107-120% of the Ah you removed from your floodies.
If the current tapers off normally in the constant voltage phase, then
you will have returned right about 100% of the Ah when you start the
final constant current phase. Since your charger fixes the finish phase
duration at 3hrs, what you could do is adjust the finish current so that
by the end of the 3 hours you will have returned an additional 10-15% of
the Ah removed.
> The Zivan has a thermal probe. The charger is mounted in the
> same place that the K&W BC-20 (from the VoltsRabbit kit) was, and
> that is adjacent to the rear pack (2x4 array of batts), which is
> in a polypropolene case. Currently the probe is duct-taped to
> the side of the polypro case, and I realize that may not reflect
> the temperature of the batts, but it is as good as I can do till
> I decide how I want to drill a hole in the case and pass the
> probe (that was one of my posts some months ago - ? on how to
> drill polypro cases). I had thought that that probe being on the
> side of that massive pack (even with the polypro) might be close
> enough to temp, but now I'm thinking otherwise from some of what
> I've seen the charger do recently, if it's pretty cool outside
> and the batteries are warm from driving.
You definitely want to get that probe inside the battery box and either
sandwhich it between a pair of the center batteries, or connect it to
one of the posts on a center battery, or stick it inside the center cell
of one of the center batteries.
I'm not aware of any tricks for drilling polypro. I expect it would be
easiest (but impractical in your case) to do the operation in a drill
press so that the drill bit isn't 'pulled' into the soft plastic such
that it 'screws' through instead of drilling. What I've found to
sometimes work with such materials is to use a reversible hand drill and
drill the hole with a sharp bit turning the 'wrong' way.
> So this (USBMC) here looks like a final constant I suggestion.
> But it doesn't appear to say for how long. I've seen you and
> Mark Hanson mention stopping when the voltage stops rising.
Right; Mark uses a dv/dt finish, and the USBMC constant current
recommendation I mentioned also comes from a dv/dt type finish
algorithm.
I you can't do a dv/dt termination with your charger, another
possibility is to try to aim to return 107-120% of the removed Ah (see
above).
> However, when I've monitored voltage, the voltage
> stops rising at 1 to 2 hours, somewhere in there, so that means
> the batts are being driven another hour (and heating up)
> unneccessarily.
If you monitor the battery/electrolyte temp, you'll probably find that
an additional hour at <6A probably doesn't raise the temperature all
that much from where it would be if you stopped early. Assuming an
average discharge of 80Ah, the extra hour represents an extra 7%
overcharge.
> At this point, I think the timer is doing the dump. I doubt the
> current is ramping back far enough on amps during the constant
> voltage phase to fall into the K2's final I setting.
My personal opinion is that if the current isn't falling off to an
appropriate level, then the constant voltage level is too high for the
batteries at their present temperature.
> That thought has crossed my mind. I don't think I added cake
> frosting :-), sooo, sometimes (even before my current troubles) I
> wonder whether the purified water I buy at Safeway (do you have
> those in BC?) is really purified.
Yep, we've got them too! ;^> However, ours (also) sell jugs of
distilled water, and that is what we use in our floodeds at work (since
there is a Safeway conveniently located across the street).
> One other item that has bothered me a bit is that a year or two
> ago I changed to a siphon water feed off of my apt deck one story
> down to the car port. The EV friend who put the beginnings of
> that together used a copper pipe or two and some brass fittings
> that go down into a 3-gallon plastic container (formerly used for
> distilled water) and attach to a long plastic hose I bought at
> the hardware store. The water is stored with just a rubber
> stopper on top of the container, and the siphon feed would only
> be in there for a few hours while I'm doing the monthly battery
> chores. Hopefully not a problem, right?
I would be suspicious that the copper and/or brass may have resulted in
some contamination of your batteries. If the batteries are
contaminated, I don't know of anything you can do about it, but if it
were me, I'd get rid of anything metallic in your watering setup and
replace it with plastic.
> I do have pdf995, and I will try that. I had the impression from
> previous fiddling with it that the output wasn't very sharp or
> something (oh, now I remember, when I was trying to print from
> Internet Explorer, it seemed like it was also printing stuff out
> from previous pdf995 runs). Well, I'll try it again and see if I
> can make it behave.
I've no idea what settings I use when I print to it from Excel, but my
plots come out clear as a bell.
> I did do an equalize charge just before (about a day) the last
> set of hydrometer readings.
Try taking s.g. readings an hour or two after the end of charge, and
then again after the batteries have sat without charging or discharging
for a day or two. If the s.g. drops noticably more in some cells than
others, you may have some internal 'shorts' causing excessive
self-discharge in those cells.
> I may have added some
> water to them once (I'd have to check my notes) and did take some
> hydrometer readings early on (they were in the 1250s temperature
> compensated), along with some light cycling.
This may tie into what Roland has been writing about doctoring the
electrolyte: it has been stated in the past that our flooded traction
batteries are 'electrolye starved', that is, on discharge the electrolye
will be depleted before the plates. My understanding is that this
prevents the plates from being deeply discharged, and causes them to
last longer in deep cycle service. So, I'm not really sure how
meaningful it is to talk about the plates and electrolyte being at
different states of charge. By my reasoning, if the electrolyte is what
is depleted first, then cells with lower s.g. will probably have less
capacity than cells with higher s.g. If the plates are not fully
charged, then continuing to charge (equalise) will continue to charge
them, and this will be reflected in a rising electrolyte s.g.; so, keep
charging until the s.g. stops rising. At this point the plates are as
charged as you are going to get them. If the s.g. is still low, and is
not the result of an excessive electrolyte level (over-watering), then
you can either top up the cell with acid or water. If you top it with
acid, you can bring the s.g. up immediately to a level you are happier
with; the stronger electrolyte will take longer to deplete on discharge,
so you will be able (for better or worse) to discharge the plates more
deeply before the cell is dead. If you top the cell up with water, you
may still be able to bring the s.g. up a bit more on subsequent
charge/equalise cycles.
I can't say which way to go, but I personally have not added acid to a
cell except when initially filling 'green', unformed batteries prior to
executing the forming charge.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
This is a summary of a wind-tunnel study on truck aerodynamics:
http://www.findarticles.com/p/articles/mi_qa3828/is_200405/ai_n9439015/
Here's where you can buy the actual study - note the title of this SAE paper:
http://www.sae.org/technical/papers/2004-01-1146
I had read the full study, can't find it now. It did mention that long-bed
trucks are effected less by leaving the gate down, but that both short- and
long-bed did better with the gate on, even if down, than if off. The amount in
most cases was so small that a difference in cross-winds (angle and intensity)
could give an entirely opposite effect. Best is a tonneau, even a short one,
and the tailgate up (the study's conclusion, not mine).
As an aside, page 20 of this online mag mentions software that predicts a lot of
the results: http://www.fluent.com/about/news/newsletters/04v13i2/04v13i2.pdf
--- End Message ---
--- Begin Message ---
Hello John,
We have about 200 left of the WKTEC flyers that Marc Geller put
together. You are welcomed to them. Let me know when you need them by.
We also had 26 "EV Expo" shirts embroidered. It cost us about $350. We
found a sewing place that had an embroidery machine. Came out quite
nice. I'll send you a picture tomorrow.
Peter
--- End Message ---
--- Begin Message ---
Tim,
I find myself in the same place - I have 3 stinkers in
my 26 battery pack, from me driving it 63 miles and likely
reversing a cell in the bastteries that had drifted out
of balance.
I will put 3 new batteries in as soon as I have clampers,
to keep the (sealed) batteries balanced.
I have driven the truck several weeks without noticing
anything more than a slightly lower voltage from the pack,
the stinkers keep reasonably up, as long as you are not racing
(some people on this list have blown a battery, but their
driving style is different than mine, I try to keep current
under 100A.
As long as the battery is not heavily loaded and overheating
there is no necessity to take it out of the loop, but removing
it (jumpering over it) does not hurt any more than also
lowering your pack voltage - your pack may be a bit stiffer,
so better during the take-offs.
Regards,
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 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-610-423-5743
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of TiM M
Sent: Sunday, October 01, 2006 10:24 PM
To: [email protected]
Subject: Re: Charging Woes
OK, I found the problem. After a hard run, ~70%
discharged, and checked individual voltages. I found
one that read 3.7V while all the rest were reading
between 6.09 and 6.11. So it looks like I have a dead
cell in my pack. I'm surprised this didn't show up
with the lighter ~30 discharge cycle.
Will it hurt anything if I continue to drive
light cycles with the bad battery? Would it be better
to remove the stinker and jumper it until I get the
replacement? How bad is it going to be to put one new
battery in with the ~14 month old pack? What other
option do I have? I'm hoping the one dead battery is
an anomaly, I was hoping to get 4 or more years out of
this pack.
TiM
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
Oh, you wanted DATA!
Just say so.
Results: up is better than down, tonneau is better than up,
mesh is worst of all, sometimes increasing the Cd from
0.48 to 0.53 by replacing solid with mesh tailgate:
http://www.findarticles.com/p/articles/mi_qa3828/is_200405/ai_n9439015
(Article showing the results of windtunnel tests.)
>From the article:
"The wind tunnel balance-measured all six components of aerodynamic force
and moment. Drag coefficients (Cd) for die trucks were normalized so the
focus could be kept on box aerodynamics. All the measurements showed the
same basic results-a small increase in drag with the tailgate down and a
larger increase with the tailgate off. These measurements were made with the
vehicle directly aligned with the stream of air."
Other studies and articles:
- Keep Your Tailgate Shut (Indiana University)
http://amos.indiana.edu/library/scripts/tailgate.html
- Aerodynamic Characteristics of General Motors Truck (University of
Michigan)
(no longer available) http://sitemaker.umich.edu/um.gm.truck
- Ford Engineer Says Tonneau Covers Provide 5 % Fuel Savings
http://www.truckgadgets.com/fuel.htm
- PUTC Interview with Honda Ridgeline Chief Engineer, Gary Flint
http://www.pickuptruck.com/html/2006/honda/ridgeline/interview.html
source: egnralnc's post at 3/22/06 on
http://www.ontariogasprices.com/Forum_MSG.aspx?topic=170702
after a lengthy up! down! shouting match
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 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-610-423-5743
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Roger Stockton
Sent: Sunday, October 01, 2006 10:30 PM
To: [email protected]
Subject: RE: Ranger doner
Rush wrote:
> Yes I have had stock tailgates, but in any case I wasn't
> talking about *me*, I was referring to *other full timers*
I understood this; I just wondered if you had actually measured and
difference/improvement since you had the means available, or if you had
just accepted the other full-timers' anecdotal claims.
> I wouldn't be too *sure* about that Roger... lots of those
> old timers are retired machinists, electricans, engineers
> etc, who are used to being able to *prove* what they say. I'm
> sure that some of them have logs with orders of precision to
> the hundredths... They love to discuss how many mpg they get
> with a headwind and with a tailwind, going down a hill and up
> a hill. They have lots of experience as a collective whole.
Great! Did any of them share any data with you *quantifying* the
difference between a stock tailgate and a vented one *without* a 5th
wheel attached?
> > It is entirely possible that the open tailgate mileage is
> > *worse* than either of the alternatives.
>
> And the opposite is true also, it is entirely possible that
> the open tailgate milage is *better* that the alternative.
> Many things are *possible* Grasshopper... <G>
Well said! ;^>
> Roger, what do mesh/screen tailgate/loading ramps have to do
> with tailgates?
Just that one should not assume that just because one can largely see
through something it will offer no resistance to the passage of air,
especially at highway speeds.
Obviously, the mesh tailgate/loading ramp on a trailer is about 3-4x the
crossectional area as a tailgate, so the effect will be much more
apparent, however, the mesh truck tailgate will also exhibit resistance
to airflow that an open tailgate will not.
The suggestion here is that the aerodynamics will be different; a mesh
tailgate will exhibit *some* resistance to airflow and so while air may
pass through it, the air will slow somewhat and slower/still air may
accumulate in front of the tailgate, similar to what might happen with a
solid tailgate, though perhaps to a lesser degree.
> As usual the thread has veered off in another direction, they
> have a tendancy to do that <G>. But the intent is there, to
> give *evidence*, however unreliable you may deem it to be
> that either supports or does not support your *assumption*.
The only issue I have is that (with the notable exception of Lynn's
recent post) the *evidence* offered has either been unsubtantiated
opinion or anecdotal in nature. This is fine for those who are
satisfied with such, but I'm the sort that requires *quantitative* data
to be convinced one way or the other. (And I'm not asking for anyone to
convince me, I'm just observing that *if* quantitative data were offered
I would find it more convincing ;^)
> If you are pissed that the thread is not following your
> direction, then that is another matter..
Naa, I don't particularly care where the thread goes; I just wanted to
make sure that people were aware that the tailgate thing was only
mentioned as an example of why one should seek *quantitative* proof that
something results in an efficiency improvement rather than assuming that
it will.
I don't *know* which tailgate option is most efficient (or if a flatdeck
is more efficient than a stock box), because I haven't measured it for
myself. However, the Mythbusters episode (however imperfect) provides
sufficient evidence for me that should I convert a pickup, I will
certainly measure the various tailgate options rather than assuming the
open tailgate is better.
> It's not that you are not trusted Roger, you have contributed
> a great deal of your knowledge and we respect your words.
Thanks for the kind words, however, in this case there really is no
reason to trust me! I haven't claimed *anything* (open/closed/vented
tailgate or flatdeck/stock box) is more efficient than something else;
all I've done is offer reasons illustrating why it is important to
question one's assumptions and evaluate the options for oneself.
> But others also have experiences and knowledge and have the
> right to express it without being told that we are sticking
> our heads in the sand...
My 'head-in-the-sand' comment was really made with Joe Strubner (sp?) in
mind, not yourself or others in this thread.
I really am hoping that if this thread doesn't just die off, *someone*
will offer up some nice hard data showing which option ws measurably
more efficient for them.
So far we've just had a couple people saying they either do or don't
believe the Mythbusters result that the closed tailgate is more
efficient, yourself reporting that 'full timers' believe their 5th wheel
vented/mesh tailgates result in improved mileage (but no indication if
this is with or without the 5th wheel attached, nor is any quantitative
data offered and you don't seem to have measured to see if your own
tailgate results in an improvement for you or not), one person
suggesting that racers have found the tailgate up to be more efficient
at high speeds, and Lynn reporting quantitative data supporting his
assertion that a partial tonneau cover improves the efficency of his
E10.
Even though some are questioning if Lynn's data is the best it could
possibly be, what speaks volumes to me is that GM originally fitted an
unusual partial tonneau cover to the vehicle. Clearly *they* believed
this was an improvement over the open box, and, one would suspect, over
an open box without tailgate. Since the partial tonneau cover is an
unusual item, and represents additional cost, I expect GM engineers
measured enough of an improvement with this arangement to justify it to
the bean counters.
Cheers,
Roger.
--- End Message ---
