EV Digest 4019
Topics covered in this issue include:
1) LED output
by Jeff Shanab <[EMAIL PROTECTED]>
2) Re: Radio Interfeence
by "Roland Wiench" <[EMAIL PROTECTED]>
3) Re: Fw: Hybrid Cars
by Bruce Weisenberger <[EMAIL PROTECTED]>
4) Re: charger isolation
by brian baumel <[EMAIL PROTECTED]>
5) RE: Individual battery monitoring
by "Don Cameron" <[EMAIL PROTECTED]>
6) Re: LED output
by "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
7) Re: LED output
by "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
8) Need a charger recommendation
by Dave Cover <[EMAIL PROTECTED]>
9) Re: LED output
by Neon John <[EMAIL PROTECTED]>
10) Re: Individual battery monitoring
by Tom Hudson <[EMAIL PROTECTED]>
11) RE: The Amazing Little Hawkers.
by "Roger Stockton" <[EMAIL PROTECTED]>
12) Re: Individual battery monitoring
by Victor Tikhonov <[EMAIL PROTECTED]>
13) Re: LED output
by "Andre' Blanchard" <[EMAIL PROTECTED]>
14) Re: LED output
by Lee Hart <[EMAIL PROTECTED]>
15) No HV cables on underside?
by Ryan Bohm <[EMAIL PROTECTED]>
16) Re: LED output
by Victor Tikhonov <[EMAIL PROTECTED]>
17) Re: Radio Interfeence (dead raptor)
by Nick Viera <[EMAIL PROTECTED]>
18) RE: The Amazing Little Hawkers.
by "Roger Stockton" <[EMAIL PROTECTED]>
19) Re: No HV cables on underside?
by "Roland Wiench" <[EMAIL PROTECTED]>
--- Begin Message ---
Both Lee and Ken are right.
If you have a lot of brightness to work with a lens can spread it out,
If you have a lot of lumens a lens can concentrate it to make it bright.
think volts,amps and a dc-dc converter. :-)
It is almost that simple, but since only the light that reaches our eye
matters, we have to figure in wavelenght, spectrum,
specularity(shinyness?), etc
almost like the argument wether linux is unix, it is only if you pay to
use the name and submitt your product for certification.
--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.300 / Virus Database: 265.6.10 - Release Date: 1/10/2005
--- End Message ---
--- Begin Message ---
I don't get the hash or hissy sounds on Radio that is tune to FM, because I
unplug the charging cord before I go.
Or if you are talking about a radio in the house, than I do somewhat. In
this country, the good sounds are on AM.
Roland
----- Original Message -----
From: "Bob Rice" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, January 11, 2005 8:12 AM
Subject: Radio Interfeence
Hi EVerybody;
At least EVerybody with a PFC series charger. Anybody else getting "hash"
or the hissys on your FM radio while charging? Havent seen anything on that
,other than electronic noise in the EV while driving. Rich? Is there an easy
"Fix" to clean up radio reception, especially the FM bands, Don't care about
AM don't listen there. A filter? I think that it , the noise, is carried on
the AC house lines, rather than an RF thing. My old Bad Boy Variac setup
never had that effect, although my Blue Box half wave across both 120 sides
of the 3 wire hookup to ground makes RF big time.
Now to this AM's problems. My Rapter just went to sleep, right in the
garage! No smoke, charge works, line contacter pulls in and..........nothin!
Damn car won't go. It's been sitting out the snow and ice in an unheated
garage, not the semi heated garage it is used to. It's way to show it's
distain?Animate perversity of inaninite objects?
Seeya
Bob
--- End Message ---
--- Begin Message ---
Hey Bob could you possible links us to the article you
are replying to?
It is a great letter.
--- keith vansickle <[EMAIL PROTECTED]>
wrote:
> hi bob
> this is a great letter I hope it get pubished. can I
> cut and paste it to my senator as you have said what
> I
> believe better than I can
>
> thanks
> keith
>
>
>
> > From: Bob Rice
> > To: [EMAIL PROTECTED]
> > Sent: Tuesday, January 11, 2005 9:29 AM
> > Subject: Hybrid Cars
> >
> >
> > Hi ! Nice Folks at SF Chronicle;
> >
> > Da ja vue as some folks say! Seems that
> California
> > can't try to clean up it's OWN air.
> >
> > Remember the CARB? Ca Air Resources Board? They
> > tried and almost succeeded in getting Electric
> Cars
> > into production. Like ONE percent of cars sold in
> Ca
> > were to be electric. GM built the fine EV-1, Ford
> > imported the Think Commuter car from Norway. In
> fact
> > they EVEN bought the company. Many EV's were
> running
> > around in CA, with their happy owners trying to
> buy
> > out their leases. NO way would they actually SELL
> > you an EV. I tried to buy the first EV-1 I drove,
> > the GM guy laughed, said that they would NEVER
> sell
> > the car outright. I said" I guess that you don't
> > want anyone running around with only ONE moving
> part
> > in your motor, thumbing your nose at EVery gas
> > station, filling up at home?"He didn't SAY
> outright
> > , only nodded in agreement.
> >
> > As we have the best Govt. Oil Money can buy,
> as
> > well as the biggest CARtel in the World, wasn't
> long
> > Big Money went to work changing, or pulling teeth
> > from ANY Ca law that could rock the boat, even
> > though it is the Titanic. With FOUR MORE YEARS
> > staring us in the face, things aren't gunna
> change,
> > at least for the better. Fuel Cells? Hah! We in
> the
> > EV fraturnity call them Fool Cells, a thing to
> suck
> > up Govt grants to " research" into making it work.
> > Too many steps, none efficient to make them work,
> be
> > easier and cheaper to just charge the advanced
> > battery system of a Electric car. Oil companies
> have
> > bought into battery research, to squelch any
> > promising systems, as they own most of the
> > photovoltaic panel outfits. God forbid! Free
> power,
> > we're talking here. They haven't taxed sunlight or
> > wind yet. But if this technology cought
> > on.......Hell! they have a tax on electrics in Or,
> > because they aren't using ang gas!! Hybrids, too,
> I
> > think?
> >
> > Electrics have, by politics become the preserve
> > of the backyard builders. I converted my old VW
> > Rabbit to electric 5 years and 70 thousand miles
> > ago. The Internet is our link to the world, Over a
> > thousand folks from all walks of life subscribe to
> > the Electric Vehicle Discussion List at
> SanJoseState
> > U. in Ca. We share tech stuff, good friends and
> > ideas, always ready to help "newbees" drive
> > electric. Ca. leads the way, with many chapters of
> > the Electric Auto Assoc. Right in SF you have
> > several chapters.
> >
> > I'm in Connecticut, read your article on line,
> > and took your challenge to write back. Small
> World!
> > But we have to think that way. What with China
> > looking for it's piece of the Oil pie, and other
> > developing countries, we have nowhere to go but UP
> > in prices and scarsity. Not to mention that all
> that
> > oil, where EVER it comes from ,fouls our air,
> drains
> > our national resources. BIG bux going overseas to
> > folks that hate us. Speaking nationwide, as CT's
> air
> > is as crappy as CA, we sit downwind from NY and
> NJ.
> >
> > Thanks for hearing me out.
> >
> > Bob Rice
>
>
> __________________________________________________
> Do You Yahoo!?
> Tired of spam? Yahoo! Mail has the best spam
> protection around
> http://mail.yahoo.com
>
>
__________________________________________________
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--- End Message ---
--- Begin Message ---
actually, the controller does have regen. so this
would mean I would need to isolate the charger.
now I am in search for a solinoid for this
application. this one on EVparts seems to fit the
current and my budget needs, but I can not find the
contact voltage rating. unless it is implied that it
is 12V.... would this, in your opinion(s), serve my
needs? I have a 120V main bank and a 96V GE 8"....
http://www.evparts.com/shopping/product_details.php?id=615&product_id=940
--- Lee Hart <[EMAIL PROTECTED]> wrote:
> brian baumel wrote:
> > Thank you, that helps a lot... Now the trick will
> be to find the
> > Peukert exponent for my particular batteries.
>
> It's different for every battery, and it changes
> with temperature and
> age. Start by assuming a value of 1.2. Modify it
> according to what you
> actually measure.
>
> > How of a battery voltage should I pick for the
> "empty"? It's a
> > 120V bank.
>
> As we've said, the pack is "dead" when it can't
> deliver "enough" current
> without dropping below 1.75v/cell. That's 105v for a
> 120v pack.
>
> Here's what happens. With a fully charged pack, it
> takes over 500a to
> pull the pack down to 105v. Your controller current
> limits before this
> point; so it is the weak link, not the batteries.
>
> As the batteries discharge, their voltage drops and
> their internal
> resistance rises. As you get below about 50%SOC, the
> controller is no
> longer the limiting factor; the batteries are. The
> current you can get
> at 105v keeps dropping as SOC falls:
>
> SOC amps at 1.75v/cell
> --- ------------------
> 50% 500a
> 40% 400a
> 30% 250a
> 20% 100a
> 10% 50a
> 0% <1a
>
> > I recently goofed. I left my car on for about a
> week and when I
> > checked the main banks voltage it was at about
> 13V!
>
> Ouch! This is very bad for battery life and
> capacity. If they are new,
> and only sat dead a short time, and were discharged
> at a very low
> current, you may be able to salvage them. They've
> probably lost half
> their life, and 20-40% of their amphour capacity.
>
> > I have been charging each separately to equilize
> and they seem to
> > be holding a charge.
>
> That's good. You'll want to leave each one on a
> low-current, >16v
> charger for a few days, to equalize the cells in
> each battery. I do this
> with a plain old transformer-rectifier charger or
> power supply, with a
> resistor or car tail light in series to limit the
> current to under 1
> amp. Leave it on until the battery voltage stops
> rising (it should go
> past 15v).
>
> Then, you'll want to do a discharge test to see how
> many amphours you
> have. You may find 1 or more batteries that are so
> much less than the
> rest that it would be better to replace them than to
> let them hold back
> the whole pack.
> --
> "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
>
>
__________________________________
Do you Yahoo!?
The all-new My Yahoo! - Get yours free!
http://my.yahoo.com
--- End Message ---
--- Begin Message ---
Hi Tom, I am (like others) building this exact thing. I have tried a number
of circuits, but I think I will go with the Dallas 1-wire DS2436 system.
There are cheaper ways to do it, but of all of the solutions I have
investigated, I like this one the best. The idea is to have a DS2436 for
each battery, go through an isolator, then feed into a uProc. From there,
the uProc, can display the data on a LCD, or log it to a bigger computer, or
what have you.
I have just got the devices, and just starting to set up the network.
Other ones to look at are:
http://www.drgw.net/workshop/solarcar/solarcar.html Detailed documents on
a solar car BMS design
http://focus.ti.com/lit/an/slua021/slua021.pdf Using the TI BQ2050 to
Monitor Lead Acid Batteries
http://genki.home.ionet.net/BattMon/BattMonArticle.html Gordon Stalling's
Central Battery Monitoring System
Don
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Tom Hudson
Sent: January 10, 2005 10:29 PM
To: ev@listproc.sjsu.edu
Subject: Individual battery monitoring
I've been off-list for a while but am now back, and I'd like to know if
anyone knows of a solution for my application.
I've got a set of Evercel batteries for my Solectria E-10 truck, to replace
the lead-acid group 24's in there now. I am working on getting the time to
rework some things on the truck so it can accomodate them with proper
ventilation, but before I install them, I want to be sure I have a battery
monitoring system set up for the pack. There will be 24 batteries, 2
strings of 12, for 144V. I want to be able to keep track of temperature and
voltage on each of the batteries at all times, both while charging and
discharging. Isolation between the modules is critical.
I want to have the temperatures and voltages logged into a small onboard
computer, so the temp/voltage sensors would have to have some sort of
computer interface capability. This would be important to make sure I
comply with the charging guidelines for these batteries, and it would enable
me to make sure I catch any problems before they get out of hand.
Primarily, if the battery temperature is too high, I want the system to
inhibit charging until the temperature drops to a safe reading.
Are there off-the shelf sensors that will do this? If not, can someone
point me to someone who would be able to help implement this system?
I'd appreciate any feedback.
-Tom
--
Thomas Hudson
http://portdistrict5.org -- 5th District Aldermanic Website
http://portev.org -- Electric Vehicles, Solar Power & More
http://portgardenclub.org -- Port Washington Garden Club
http://portlightstation.org -- Light Station Restoration http://klanky.com
-- Animation Projects
--- End Message ---
--- Begin Message ---
I've been following this discussion, and when Ken Trough began discussing
Lee Hart instead of LEDs, I decided to jump in and see if I could pull the
discussion back to hardware instead of software. <g>
What we want to know (at least what ^I^ want to know ;-) is whether LED
headlamps are really that much more efficient than the alternatives. If they
are, is it worth the cost? Is there something that's even better than LEDs?
Efficiency, or luminous efficacy, is usually measured in lumens per Watt.
Curiously, Luxeon don't list power consumption of their LEDs in the spec
tables on the web pages, but I downloaded from their site a pdf document on
"electrical drive information" which I think has some useful information that
will allow us to derive the power requirements.
Now, I'm not an engineer, so my calculations may be off. I invite anyone
who's an engineer to review the following and correct any misapprehensions.
It appears to me that Luxeon say a "Star," apparently a mounted "Emitter,"
is the building block of their lights. It may be driven with a constant
current
source of 350ma. According to their specs, at this current level a white Star
will emit 31 lumens. They don't specify voltage drop across the LED at that
current, though, and to calculate lumens per watt, we need to know the
power consumed (voltage * current).
However they DO provide information on driving a Star with a constant voltage
(6 volt) power supply, saying it will require either an 8 ohm or 11 ohm series
resistor. It appears that the different resistance requirements apply to
different variants of the product. I don't understand the product differences
so
I calculated the efficacy using both values (see below).
Here's where I may be off, so again I invite correction if I am. But if we
take it
that the LED requires .35 amp and the source is 6v, with E=IR, the voltage
drop across the 8 ohm resistor will be .35 * 8 = 2.8 volts. This means that
the voltage drop across the LED is 3.2 volts. At 350ma, the LED is thus
consuming 1.12 watts to produce 31 lumens. (Right?)
If we take the series resistor as 11 ohms, we have a drop across the LED of
2.15 volts and thus a power consumed by the LED of 0.75 watts.
If I have it right here, a Luxeon white LED has a luminous efficacy of either
27.7 (call it 28) or 41.33 (call it 41) lumens per watt.
Please note that this is the efficiency for the Luxeon using a true constant
current source. It does NOT account for the losses in the series resistor if
the LED is powered with a constant voltage source. These losses can be
substantial. If we assume a 6 volt battery is powering the LED, the total
power consumed by resistor and LED is 2.1 watts. Something like half the
power consumed is wasted in the series resistor as heat. This drops the
Luxeon's efficacy to 15 lumens per Watt.
With that in mind, let's see how Luxeon's efficacy compares.
Luxeon white LED, 6 volt battery and resistor: 15 L/W
Halogen headlamps: 16 - 23 L/W (low beam - high beam)
Luxeon white LED, constant current supply: 28 - 41 L/W
Xenon HID headlamps: 90 L/W*
*It's not clear to me whether this includes the ballast or not.
Now, just for the heck of it, some household and business use comparisons:
100 watt A19 lamp (household incandescent light bulb): 17 L/W
Other incandescents: 4 - 20 L/W
Tungsten halogen lamps, typical: 18 - 22 L/W
Luxeon white LED, CC power supply: 27 - 41 L/W
Compact fluorescent (typical, including ballast): 45 - 60 L/W
32 watt T8 tubular fluorescent, middle of lifespan: 80 L/W
32 watt T8 tubular fluorescent, new: 95 L/W
Metal halide: 80 - 125 L/W
Low pressure sodium: 135 - 185 L/W
I think the numbers speak for themselves.
It looks to me as if LEDs (Luxeon or others) can shine, if you'll pardon the
pun, when they're replacing low-wattage incandescent bulbs, such as in
indicators and flashlights. There they have a clear efficiency advantage.
They also play nicely with battery power sources, because unlike
incandescents they don't draw more current as the voltage declines toward
end of life or charge. They have longer lives by far than incandescents.
Finally, if you need red, yellow, green or blue light, as in indicators or
automotive tail, brake, or turn lights, LEDs have an advantage because all the
light they emit is in the right range - nothing is wasted in filtering.
However, where lots of white light is needed or the light uses only a tiny
fraction of the battery's energy, right now the advantages of white LEDs,
including Luxeon's, don't seem quite as compelling.
If powered by a well-designed power supply (assuming it's 100% efficient!)
they appear to have a luminous efficacy between 22% and 128% greater than
halogen incandescent headlights. Tthe actual improvement probably
depends on several factors and comes at a substantial increase in cost and
complexity. Highly efficient, current-regulated, PFC power supplies don't
usually come in the form of Chinese-made wall warts. <g>
In the real world of small, cheap EVs such as scooters, the Luxeon is more
apt to be driven by a battery and series resistor. In this configuration, it's
actually LESS efficient than a halogen headlight!
What's more, Xenon HID, OTOH, offers a still greater improvement in efficacy,
though they may be less practical for scooters - I get the impression that
they need a bit of extra room for the ballast (right?) For larger EVs, though
I
haven't done a cost analysis, I suspect that the improvement per additional
dollar is appreciably higher for the HID lights. That calculation will be left
as
an exercise for the reader. <g>
David
--- End Message ---
--- Begin Message ---
Oops, after I wrote the last message, I saw that there was more to the pdf file
from Luxeon. Duh. Further down we find:
Typical Characteristics at 350mA, Junction Temperature, TJ = 25oC
Color WHITE 5500K
Forward test current 350ma
Typical forward voltage 3.42 v
Minimum luminous flux 13.9 lumens
Typical luminous flux 18 lumens
This means a Luxeon Star consumes 1.2 Watts to produce 18 lumens,
which equates to about 15 lumens per watt. It's thus LESS efficient than
either a halogen headlight bulb or a household 100 watt bulb.
David
--- End Message ---
--- Begin Message ---
Hi all,
I need to buy a utility charger for around the garage. I don't need a pack
charger, just one I can
use to charge ICE batteries, deep cycle batts, and may be a little more
flexibility built in. This
is for playing and learning. And to replace my old and rusty Sears charger.
After reading all your
emails, I want more options than just a 2/10 amp switch.
I'll probably never need to do more than charge an individual 12v battery with
this charger, but I
would like some ability to experiment with some of the different charging
routines you guys are
always chatting about. The first thing I want to do is charge enough batteries
so I can set up my
Curtis on the bench for testing. Can I do this with just a power supply?
I haven't pick out a traction pack yet, but I do have 96 volts of NiCads for
some project. I'm
thinking about AGMs for my pending project, but I just haven't made up my mind
yet.
Oh yeah, and I can't spend hundreds and hundreds of dollars.
Would I be better served to buy a variac and build a charger?
Thanks
Dave Cover
PS. I did rip a nice transformer out of a 20+ year old Sears microwave. It's
big and heavy and I
hope I can use it for something. I'm defintely not going to build a Bad Boy
though.
--- End Message ---
--- Begin Message ---
Some other things to consider that LEDs even worse. Note the junction
temperature of 25 deg. That is impossible in the real world. The
junction temperature may be 80 deg or more when operated at the rated
current in air. Both the UV led part and the phosphor that makes the
while light produce less light as the temperature rises.
Second thing to realize is that the phosphor is very heavily excited,
resulting in a rather short life. The numbers they quote are for new
phosphor. I'm sure that PDF has a suitable chart showing light decline vs
time. From memory, the half life is around 1000 hours.
For very power efficient applications it is still hard to beat the HID.
If instant restrike capability isn't a requirement (mandatory for cars,
not necessarily so for scooters, etc) there is a wide variety of low
wattage HIDs available. I have a tiny little 15 watt integrated reflector
lamp and driver that is absolutely dazzling to look at and will light my
whole shop to daylight brilliance. It takes about 30 sec to cool enough
to restrike.
John
On Tue, 11 Jan 2005 14:13:49 -0500, "David Roden (Akron OH USA)"
<[EMAIL PROTECTED]> wrote:
>Oops, after I wrote the last message, I saw that there was more to the pdf
>file
>from Luxeon. Duh. Further down we find:
>
>Typical Characteristics at 350mA, Junction Temperature, TJ = 25oC
>
>Color WHITE 5500K
>Forward test current 350ma
>Typical forward voltage 3.42 v
>Minimum luminous flux 13.9 lumens
>Typical luminous flux 18 lumens
>
>This means a Luxeon Star consumes 1.2 Watts to produce 18 lumens,
>which equates to about 15 lumens per watt. It's thus LESS efficient than
>either a halogen headlight bulb or a household 100 watt bulb.
>
>David
>
---
John De Armond
[EMAIL PROTECTED]
http://bellsouthpwp.net/j/o/johngd/
Cleveland, Occupied TN
--- End Message ---
--- Begin Message ---
Don, Roy and Joe, THANK YOU for the input. This gives me an excellent
starting point.
As usual, you can't beat the EV List for incredibly helpful people.
-Tom
--
Thomas Hudson
http://portdistrict5.org -- 5th District Aldermanic Website
http://portev.org -- Electric Vehicles, Solar Power & More
http://portgardenclub.org -- Port Washington Garden Club
http://portlightstation.org -- Light Station Restoration
http://klanky.com -- Animation Projects
--- End Message ---
--- Begin Message ---
Joe Smalley [mailto:[EMAIL PROTECTED] wrote:
> > I think that mostly what we disagree on is our definition of
> > 'meaningful' current.
> >
> > As long as *any* (OK, almost any ;^) current at all is
> > passed through the less full monoblocks, they will charge
> > and will eventually become full
>
> This point can be taken several different ways. I have always
> wondered what current is appropriate for floating PbA
> batteries below which they are not charging.
Point taken. This is why I added the "almost any" disclaimer. For the
purpose of this discussion, I think we agree that meaningful current
must mean sufficient current that charging is actually occuring.
> > Nope; we agree: if short charge time is the priority, then
> > regs are a solution.
>
> The other solutions proposed are 1) a Balancer that can be
> switched around to charge each battery invidually or 2)
> Modular chargers that put the final few AHr into each monoblock.
Right; these are hardware solutions. I am proposing that a software
solution may be possible in the form of more sophisticated charge
algorithms.
> When a pack gets this neglected, I normally use a one hour
> time-out at end of charge to terminate the charge early. I
> then run it down at least 10% of nameplate and charge it up
> again. The second cycle has a noticeably shorter absorption phase.
Yes, I think we agree that a little TLC usually improves this sort of
behaviour.
My point in providing this example is that if one leaves their EV
neglected all winter, then when they yank it out of the snowbank to
charge it up, they cannot rely on regs to protect their batteries from
venting.
> The Sonnneschein factory engineer called the effect "storage
> latency."
Regardless of what it is called, I believe that a large part of what is
happening is that when a battery sits for long periods its cells
self-discharge at varying rates and so the cells can become dramatically
imbalanced. The imbalance results in a battery that gasses at a lower
terminal voltage because one cell may be over the gassing voltage while
several others are still well below it.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
/plug
Another potential option: in a few month Smooth Talk BMS
will be ready, it will do what you want and more.
http://www.metricmind.com/bms.htm
Described is 3.6V version, but it is trivial to modify
it for 6V or 12V battery (which will happen after 3.6V version
is ready), especially if you only want to monitor it.
Of course I'll post when something interesting develops.
/unplug
Victor
'91 ACRX - something different.
Tom Hudson wrote:
I've been off-list for a while but am now back, and I'd like to know if
anyone knows of a solution for my application.
I've got a set of Evercel batteries for my Solectria E-10 truck, to
replace the lead-acid group 24's in there now. I am working on getting
the time to rework some things on the truck so it can accomodate them
with proper ventilation, but before I install them, I want to be sure I
have a battery monitoring system set up for the pack. There will be 24
batteries, 2 strings of 12, for 144V. I want to be able to keep track
of temperature and voltage on each of the batteries at all times, both
while charging and discharging. Isolation between the modules is critical.
I want to have the temperatures and voltages logged into a small onboard
computer, so the temp/voltage sensors would have to have some sort of
computer interface capability. This would be important to make sure I
comply with the charging guidelines for these batteries, and it would
enable me to make sure I catch any problems before they get out of
hand. Primarily, if the battery temperature is too high, I want the
system to inhibit charging until the temperature drops to a safe reading.
Are there off-the shelf sensors that will do this? If not, can someone
point me to someone who would be able to help implement this system?
I'd appreciate any feedback.
-Tom
--- End Message ---
--- Begin Message ---
Which brings us to the absolute most important characteristic of an auto
headlight.
It must not be blinding to other drivers. If your headlights are not
bright enough you can always slow down, if they are blinding other drivers
the only thing they can do involves a 12 gage and buckshot.
Thanks,
Andre' B.
At 02:05 PM 1/11/2005, you wrote:
<< snip >>
For very power efficient applications it is still hard to beat the HID.
If instant restrike capability isn't a requirement (mandatory for cars,
not necessarily so for scooters, etc) there is a wide variety of low
wattage HIDs available. I have a tiny little 15 watt integrated reflector
lamp and driver that is absolutely dazzling to look at and will light my
whole shop to daylight brilliance. It takes about 30 sec to cool enough
to restrike.
John
--- End Message ---
--- Begin Message ---
Lee said:
>> LUMENS are a measure of illumination -- the total quantity of
>> light delivered in all directions.
>>
>> CANDELA are a measure of brightness -- how bright the light
>> appears in ONE direction only.
>
>> [headlight usage] requires illumination; lots of lumens or
>> candlepower.
Ken Trough wrote:
> No offense Lee, but you are lost in a text book and talking out
> of both sides of the equation. First you say that it is lumens
> that is the critical factor, than you say that headlights need
> lots of lumens OR candlepower (candelas).
Sorry for confusing you. Candlepower measures illumination, like lumens.
1 candlepower = 12.566 lumens.
> Honestly, this is why conversations like this make me crazy.
> You counter practical experience with technical doublespeak...
Actuall, I was trying to do the opposite! The marketing data presented
so far has all been doublespeak; meaningless babble that can't be
compared.
> Then when someone bothers to FIND you a number...
Please, where is the number? Is there an email that I missed? All I have
seen is a quote from Luxeon that says they have lights that deliver "up
to X lumens", but they don't say what product, how much power it takes,
what it costs, or any details.
I can't tell if this is a real product, or a laboratory experiment. I
can't tell if it took 1 or 1000 LEDs to get this much light.
But there are endless pages, showing hundreds of flashlights making
brighness claims. Not a single one has any test results.
Would you buy batteries from someone who can't tell you the voltage or
amphour capacity, but who just describes them as "high voltage" and
"super capacity"?
> Honestly, I don't believe that the numbers are going to be helpful,
> because the products can be driven at different power levels for
> different luminosities anyway, and it is very hard to judge abstract
> equivalencies between disparate products and technologies without
> seeing what these products do when installed on the vehicle.
There are meters that directly measure light levels in an objective way.
Every camera store has them.
> My original statement stands. A triple cluster of luxeon elements
> combined with the focusing optics will THROW enough light ahead
> of you to be a suitable replacement for a basic headlight at a
> MUCH lower power level.
Then PROVE it! Use a Luxeon cluster to light up something, and take a
reading with a camera light meter. Record the number. Then illuminate
the same object with a regular car headlight in the same place. Record
the number. Then you will have an objective basis to say how they
compare.
If you use enough Luxeons to get the same light level reading, you can
measure the power that the Luxeons and headlight each consume. Then you
have an objective basis for comparing their efficiency.
Note: If you are measuring illumination, you use the meter to measure
the light reflected off something (a wall, your garage door, the road
ahead, etc.) You don't shine the light source directly into the meter --
if you do, you are measuring brightness.
--
"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,
Seth and Joe, thanks for the information. Seth, your comments have really
caught my attention. I will be taking your advice and not driving the 200sx
until I resolve these issues.
You say that HV cables should not be run on the underside of the vehicle. I
*do* have them running where the gas lines ran, protected from a direct hit by
running along side the frame rails. I didn't like putting them there, but
didn't think it was preferable to put them in the passenger compartment. Since
I am planning a re-route on the wires anyways, should I run them through the
passenger compartment somehow? That seems like a bad idea to me, but how have
others done this?
Thanks a ton,
Ryan
*********
What you have done is the #1 cause of EV fires that I know of. Salt
slush in Anderson connectors results in a short that doesn't pop ...
Not that traction wires should ever run along the bottom of
the car, they are asking to be compromised or severed.
Crouse Hinds Cam-Lok makes the connector that should replace that
Anderson. Not nearly as easy to use as an Anderson, but actually made
for that environment.
Good luck
Seth
*********
--- End Message ---
--- Begin Message ---
AFAIK, ability to direct the light so it does not blind
others has little to do with brightness or lumens output the
light source provide. Once in a while I see oncoming car with badly
adjusted regular lights which blinds me, followed by Lexus or such
with far more powerful HID lights (much brighter light spots *on the
road* in front of him), which I barely see as I approach him from
the opposite direction. The trick is the reflector design such that
NO 9or minimal) light goes above certain height. Due to close
proximity of deflector and focusing system to the light source
(arc or fialment) absolute black and white separation is impossible
due to defraction of the light ("bending" around obstacles, in this
case, deflectors and chutters), but degree of this effect is
greatly reduced in good designs.
Victor
Andre' Blanchard wrote:
Which brings us to the absolute most important characteristic of an auto
headlight.
It must not be blinding to other drivers. If your headlights are not
bright enough you can always slow down, if they are blinding other
drivers the only thing they can do involves a 12 gage and buckshot.
Thanks,
Andre' B.
At 02:05 PM 1/11/2005, you wrote:
<< snip >>
For very power efficient applications it is still hard to beat the HID.
If instant restrike capability isn't a requirement (mandatory for cars,
not necessarily so for scooters, etc) there is a wide variety of low
wattage HIDs available. I have a tiny little 15 watt integrated
reflector
lamp and driver that is absolutely dazzling to look at and will light my
whole shop to daylight brilliance. It takes about 30 sec to cool enough
to restrike.
John
--- End Message ---
--- Begin Message ---
Hi,
> My Rapter just went to sleep, right in the garage! No smoke,
> charge works, line contacter pulls in and..........nothin!
> Damn car won't go.
This sounds like the same problem I had with my Raptor controller. My
problem was that the controller would power up, light up the green LED,
and pull in the main contactor, but then give NO output power. OR
sometimes it would work fine for awhile, then the output would suddenly
drop out (no PWM) or become very intermittent. Then the Jeep and I would
go home on a tow truck :-/
The problem was the connection between the control board and the power
board in the controller was a little corroded, and that one contact in
the female end of the connector had cracked.
Replacing the female connector on the control board solved that problem.
-Nick
1988 Jeep Cherokee 4x4 EV
http://Go.DriveEV.com/
--------------------------------------------
On Tue, 2005-01-11 at 09:12, Bob Rice wrote:
> Hi EVerybody;
>
> At least EVerybody with a PFC series charger. Anybody else getting
> "hash" or the hissys on your FM radio while charging? Havent seen
> anything on that ,other than electronic noise in the EV while driving.
> Rich? Is there an easy "Fix" to clean up radio reception, especially
> the FM bands, Don't care about AM don't listen there. A filter? I
> think that it , the noise, is carried on the AC house lines, rather
> than an RF thing. My old Bad Boy Variac setup never had that effect,
> although my Blue Box half wave across both 120 sides of the 3 wire
> hookup to ground makes RF big time.
>
> Now to this AM's problems. My Rapter just went to sleep, right in
> the garage! No smoke, charge works, line contacter pulls in
> and..........nothin! Damn car won't go. It's been sitting out the snow
> and ice in an unheated garage, not the semi heated garage it is used
> to. It's way to show it's distain?Animate perversity of inaninite
> objects?
>
> Seeya
>
> Bob
--- End Message ---
--- Begin Message ---
Joe Smalley [mailto:[EMAIL PROTECTED] wrote:
> > Correct me if I am wrong, but once the PFC hits its voltage
> > setpoint, isn't the charge control limited to setting how long
> > the timer lets the charger run before shutting it down?
>
> The charger receives no indication that the last module has
> reached final voltage. The operator needs to total up all the
> regulator voltages to determine the final target voltage for
> the pack.
Ah, but this doesn't address the question I asked. ;^>
My understanding is that the PFC runs constant current until it hits the
voltage setpoint and then simply holds that voltage until the user
configured timer shuts it down. IF the reg feedback signal causes the
PFC to behave as if the voltage setpoint had been hit, then it would
simply terminate the charge a fixed time after the cutback signal is
seen, which would leave some modules undercharged.
IF the regs provided both an 'AND' and 'OR' feedback signal then the PFC
charger could both yank back its output to keep from locking any regs
full on and could continue charging until all regs are firing (or a
maximum time elapses). The 'OR' signal is what I understand the present
feedback signal to be, that is, if *any* reg asserts the cutback line,
the charger yanks back its output. The 'AND' signal would only fire
when *every* reg is firing, and could either tell the charger to stop or
to start the timer so that the charge terminates after X minutes with
all regs flashing.
> No, the reg feedback line is not inactive. We are trying for
> about a 30% to 60% blink rate.
Clearly I don't know the details of your feedback line impelentation; a
30-60% blink rate suggests to me that the feedback line is inactive
40-70% of the time, but your response indicates that the feedback line
is not inactive even at this duty cycle/blink rate.
> > Is there something magic about the number 10? My experience is
> > primarily with shorter strings, like 6 modules, which is
> > still plenty long enough to see varying module voltages.
>
> Longer strings have a higher probability of deviation. Most
> of the problems we have seen are experienced above 96 volts.
I wonder if you have seen most of your problems above 96V simply because
most of your experience with long strings is with strings above 96V.
Battery manufacturers typically consider anything more than 48V to be a
long string with respect to special charging practices, and I have seen
the voltage problems/behaviour you have identified with strings as short
as 48V (I expect I would see it at 24V too, but I usually deal with
longer AGM strings than that).
> > So, what is so special about getting the batteries to or
> > above 14.8V?
>
> Something about positive grid corrosion causing problems when
> the battery is undercharged.
I think it is the negative grid you are thinking of. I believe that
positive grid corrosion is associated more strongly with overcharging
and extended periods at elevated voltage (float charge).
> I think it was Optima that
> stressed that each monoblock will deteriorate if it was not
> taken over gassing voltage occasionally.
I should, perhaps, have been more specific; I was specifically referring
to what is so special about getting the batteries to/over 14.8V as an
absorption target. If you perform a constant current finish and allow
the voltage to rise unrestricted (or even if you cap it somewhere within
your comfort range, perhaps 15.6-17V), as recommended by Optima, then
the battery is taken over the gassing voltage even if the absorption
threshold is lower than 14.7V.
I find it interesting when people selectively dismiss or adhere to only
those aspects of the manufacturer's recommendations that mesh with their
personal beliefs ;^>
> The difference is in the implementation. We are presently
> trying the lower current with the feedback into the charger.
> The earlier (non feedback) method was the full three amps.
> The older method required the user to set the pack voltage
> very accurately whereas the 'software in the loop' method
> presently being used does not require the voltage setpoint to
> be accurately set by the user. It is simpler to set up and
> maintain as well as safer for the battery.
This seems backwards to me, but I expect that is because I am not
familiar with the implementation details of your system. I would have
expected that the presence of the feedback signal would have allowed a
higher charge current to be used since the regs can now force the
charger to back off if they find the current too high.
> This is a perfectly valid approach. It costs less and takes
> longer to perform. If you have the time, you can save some
> money doing it that way.
>
> Speed costs money. How fast do you want to go?
Thank you; this is my point entirely. Regs can allow a faster charge,
but add cost. As Rich points out, if it takes a week to recharge
without regs, then going reg-less is not an option, however, if suitable
algorithms can be developed which allow recharging in 8-12hrs then it
may be an option for some.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
You could run flexible sealtite conduit that is waterproof with straight, 90
degree or 45 degree box connectors.
When running this type of conduit, you can clamp it to the bottom using
conduit pipe clamps. Hole saw though on both ends for installing the
sealtite box connectors with a o-ring you add to the flange surfaces.
If you used a 45 or 90 degree connector on the ends, it is best to install
the cables in this conduit before installing the box connectors.
You could used exhaust tubing with header end flages that can be bolt to a
flat bulkhead. In some cars it may be difficult to bend a 2 inch pipe which
is need to carry 3 power cables.
If you are building a EV, it is best to run a large wire way from front to
rear inside the car. My wire wire is 10 inches wide by 10 inches high and
runs like a center console between the seats that go from the fire wall and
to the back compartment behind the seats. There are take offs to the dash
instruments and to a switch panel that is located on top of this console
like wireway.
Also there are hinge and removable panels that are access to circuit breaker
panel. All indicators and switches are mounted on removable panels that can
be unplug with small gangable 10 to 30 amps Anderson Power connectors.
I went to car dealers to look and measure center consoles. I found one that
may be of a different car that I have, which fit just right. Bought two of
them, so I can extended it all the way back to the rear compartment.
I also have a transmission shifter in this console, that I added and
relocated to the corrected position.
When running wires and cables in this wireway, you should keep them
separated, higher voltage set and low voltage set. Some critical indicator
and sensor wires should be shield. Also install in enclose wirelooms inside
the wireway. For the larger power cables, I used a black flexible vacuum
cleaner hose that looks just like the smaller split black wire looms. You
could used different color wire looms for different circuits.
When I ran my conduit type wirelooms from the wireway to waterproof cast
aluminum enclosures that is in the motor bay, I used black plastic cable
connectors that fit these wirelooms, that I pick up from a electrical supply
house.
It is best to totally enclose all devices and connections in a EV. I also
added a neoprene rubber sheeting that I fasten to the inter fender walls and
drape over the suspension to prevent splash up on to the motor and
equipment.
Roland
----- Original Message -----
From: "Ryan Bohm" <[EMAIL PROTECTED]>
To: "Electric Vehicle Discussion List" <ev@listproc.sjsu.edu>
Sent: Tuesday, January 11, 2005 3:20 PM
Subject: No HV cables on underside?
> Hi,
>
> Seth and Joe, thanks for the information. Seth, your comments have really
> caught my attention. I will be taking your advice and not driving the
> 200sx until I resolve these issues.
>
> You say that HV cables should not be run on the underside of the vehicle.
> I *do* have them running where the gas lines ran, protected from a direct
> hit by running along side the frame rails. I didn't like putting them
> there, but didn't think it was preferable to put them in the passenger
> compartment. Since I am planning a re-route on the wires anyways, should
> I run them through the passenger compartment somehow? That seems like a
> bad idea to me, but how have others done this?
>
> Thanks a ton,
>
> Ryan
>
>
> *********
> What you have done is the #1 cause of EV fires that I know of. Salt
> slush in Anderson connectors results in a short that doesn't pop ...
> Not that traction wires should ever run along the bottom of
> the car, they are asking to be compromised or severed.
>
> Crouse Hinds Cam-Lok makes the connector that should replace that
> Anderson. Not nearly as easy to use as an Anderson, but actually made
> for that environment.
>
> Good luck
>
> Seth
> *********
>
>
--- End Message ---
