EV Digest 2685
Topics covered in this issue include:
1) Re: Wind turbines in Iowa?
by [EMAIL PROTECTED]
2) Re: Motor, Surprise!
by "garry" <[EMAIL PROTECTED]>
3) Re: AC controllers
by "Mark Thomasson" <[EMAIL PROTECTED]>
4) Re: AC controllers
by [EMAIL PROTECTED]
5) RE: Motor, Surprise!
by "Andre Blanchard" <[EMAIL PROTECTED]>
6) Buck converters (was Re: AC controllers)
by Peter VanDerWal <[EMAIL PROTECTED]>
7) RE: AC controllers
by "Andre Blanchard" <[EMAIL PROTECTED]>
8) Buck Convertors
by [EMAIL PROTECTED]
9) Re: Looking for a scooter
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
10) 1221C Curtis case disassembly
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
11) Morad 1500 scooter
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
12) RE: Wind turbines in Iowa?
by Mike Chancey <[EMAIL PROTECTED]>
13) Re: 1221C Curtis case disassembly
by "Roy LeMeur" <[EMAIL PROTECTED]>
14) RE: That time of the year again... - cable coiling
by "Mark Fowler" <[EMAIL PROTECTED]>
15) Re: 1221C Curtis case disassembly
by [EMAIL PROTECTED]
16) Re: cable coiling
by John Bryan <[EMAIL PROTECTED]>
17) Re: Wind turbines in Iowa?
by Lee Hart <[EMAIL PROTECTED]>
18) Re: 1221C Curtis case disassembly
by Otmar <[EMAIL PROTECTED]>
19) Regen on series
by "Rod Hower" <[EMAIL PROTECTED]>
20) Re: Motor, Surprise!
by Lee Hart <[EMAIL PROTECTED]>
21) EVLN(Pitzer president plugs-in)
by Bruce EVangel Parmenter <[EMAIL PROTECTED]>
22) EVLN(State considers abandoning EVs for fuel vehicles)
by Bruce EVangel Parmenter <[EMAIL PROTECTED]>
23) EVLN(Sadly, this is not how automobile manufacturers think)
by Bruce EVangel Parmenter <[EMAIL PROTECTED]>
--- Begin Message ---
I get mine from <www.newwindenergy.com>
Stay Charged!
Hump
----- Original Message -----
From: "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
Date: Thu, 27 Mar 2003 15:59:51 -0500
To: [EMAIL PROTECTED]
Subject: Re: Wind turbines in Iowa?
> On 27 Mar 2003 at 9:42, Chip Gribben wrote:
>
> > Hey Rod, what you could do is purchase wind generation credits so that some
> > of the electricity you use can be credited towards electricity generated by
> > wind power. Several folks in EVA/DC have signed on.
>
> Please post details to the list if available. This is (or should be) of
> interest to all EV users. Thanks.
>
>
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> Want to unsubscribe, stop the EV list mail while you're on vacation, or
> switch to digest mode? See http://www.evdl.org/help/
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> David Roden - Akron, Ohio, USA
> 1991 Solectria Force 144vac
> 1991 Ford Escort Green/EV 128vdc
> 1970 GE Elec-trak E15 36vdc
> 1974 Avco New Idea rider 36vdc
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> Thou shalt not send me any thing which says unto thee, "send this to all
> thou knowest." Neither shalt thou send me any spam, lest I smite thee.
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
>
Stay Charged!
Hump
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--- Begin Message ---
Hi Rhett,
Please excuse my ignorance, but where, in here, is the Lenz counter to
direction of motion force, that is generated when ever a magnet and a coil
come into proximity, hidden.
I have heard it called back emf which I tend to use, but everyone says its
not and I have heard it referred to as eddy currents.
I believe it is responsible for some of the heat loss in a motor as it is
dissipated into the rotor core and I thought it might come into the
"armature (+ brush) resistance " if its not in the heat loss ?
Thanx
Garry Stanley
Cable.net.nz
--- End Message ---
--- Begin Message ---
Lee, Excellent circuit! You accomplish the same thing as the original with
only 5 instead of 9 contactor coils, plus getting built in protection
against shorted batteries from welded contacts, a significant improvement.
Interestingly, there are still 9 contacts. We could drop one contact by
making one of the SPDT's into two SPST's, and dropping K5. But then we
would need more mechanical or electrical interlocking to prevent the shorted
battery problem again. The seven step circuit could be done with only 4
contactors (2 less than the original). All I need now is a separately
excited motor designed for high starting torque.
I'm still trying to understand how the PWM controller acts as a DC
transformer ( using the DC to DC Buck converter principle?) to put all
those extra electron to the motor. Are there any good tutorial type
references about this? Thanks,
Mark T.
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, March 26, 2003 2:26 AM
Subject: Re: AC controllers
> Lee Hart wrote:
.............................................
I'm wondering why you couldn't do your 1-2-4-8 switching with 4
> SPDT contactors like this (view with fixed width font):
> _______
> | | K4
> +__|__ NC O ___________to motor +
> 48v ___ / COM
> | NO O/
> |_______|_________
> |
> _______ |
> | | K3 |
> +__|__ NO O _______|
> 24V ___ / COM
> | NC O/
> |_______|_________
> |
> _______ |
> | | K2 |
> +__|__ NO O _______|
> 12V ___ / COM
> | NC O/
> |_______|_________
> |
> _______ |
> | | K1 |
> +__|__ NO O _______|
> 6V ___ / COM
> | NC O/
> |_______|____________to motor -
>
> This only requires 4 contactors. You can still get any voltage from 0v
> to 90v in 6v steps. No combination of contactors K1-K4 being on/off ever
> shorts any battery.
>
> You might want a 5th contactor (K5) for an all-off condition (as shown,
> when K1-K4 are all off they short the motor, which would brake it to a
> stop).
>
> The contactors could all be SPST if the NC-COM contact were replaced
> with diodes. You couldn't do regen with the diodes, however.
>
....................................
> --
> Lee A. Hart Ring the bells that still can ring
> 814 8th Ave. N. Forget your perfect offering
> Sartell, MN 56377 USA There is a crack in everything
> leeahart_at_earthlink.net That's how the light gets in - Leonard Cohen
>
--- End Message ---
--- Begin Message ---
> I'm still trying to understand how the PWM controller acts as a DC
> transformer ( using the DC to DC Buck converter principle?) to put all
> those extra electron to the motor. Are there any good tutorial type
> references about this? Thanks,
It's not acting like a DC transformer.
It is causing it's DC input to pulse on the output, which of course makes it's output
AC (pulsating DC really). The motor coils therefore are seeing an AC waveform, The
motor therefore is now a transformer that spins, just as a transformer is a motor that
doesn't. This action of course would not be possible without that dang-blasted Back
EMF.
Stay Charged!
Hump
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--- Begin Message ---
Here is a small sample of the info available on the web.
http://www.sciencejoywagon.com/physicszone/lesson/08magnet/lenslaw/lenz.htm
http://www.launc.tased.edu.au/online/sciences/physics/Lenz's.html
http://members.optusnet.com.au/~emeryrg/9_3_motors_&_generators.htm#Lenz
Andre' B. andre-at-usermail.com
If something cannot be defined, it does not exist.
Isaac Newton
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of garry
Sent: Thursday, March 27, 2003 3:33 PM
To: [EMAIL PROTECTED]
Subject: Re: Motor, Surprise!
Hi Rhett,
Please excuse my ignorance, but where, in here, is the Lenz counter to
direction of motion force, that is generated when ever a magnet and a coil
come into proximity, hidden.
I have heard it called back emf which I tend to use, but everyone says its
not and I have heard it referred to as eddy currents.
I believe it is responsible for some of the heat loss in a motor as it is
dissipated into the rotor core and I thought it might come into the
"armature (+ brush) resistance " if its not in the heat loss ?
Thanx
Garry Stanley
Cable.net.nz
--- End Message ---
--- Begin Message ---
Good question, probably time to describe this again.
A PWM Buck converter needs four main components.
A input filter capacitor
A switch (usually a power transistor of some kind)
A freewheeling diode
and an inductor (the motor in this case)
Now for a little electronics basics:
A capacitor resists a change in voltage. It does this by absorbing
voltage that is higher than it's current charge and supplying voltage
when the voltage drops below it's current charge.
An inductor resists a change in current. What happens when you
initially try to push current through an inductor is that this creates
an expanding magnetic field. This expanding field creates EMF in the
coil that resists the creation of the field and the flow of current. So
the current doesn't just instantly start flowing, it builds up slowly
(talking microseconds here), until it reaches what ever current the
circuit will allow (in a DC circuit this is limited only by resistance).
When you shut of the current the magnetic field in the inductor starts
to collapse. This also creates EMF, only this EMF doesn't fight the
current but is of the opposite polarity and tries to keep the current
flowing.
If there is no path for the current the the voltage across the coil
builds up in an effort to force current to flow, this is what causes
arcing of contacts.
If there is a path for current to flow (like a diode) then the current
continues to flow and slowly decays (due to the resistance in the
circuit)
OK back to the Buck converter.
When the switch turns on, the motors inductance initially fights the
flow of current but eventually (again microseconds here) current starts
flowing. When the voltage builds up to the desired level the switch
turns off.
The way the freewheeling diode is installed it is reverse biased by the
voltage through the switch (so you don't waste any power in it).
When the switch turns off the motor's inductance wants the current to
keep flowing. It is actually trying to draw, or suck current.
The path for this current is through the freewheeling diode, which now
ends up forward biased by the motor sucking current.
Naturally since noting is creating this current flow except the
collapsing field in the motor, it starts to decay and the voltage starts
dropping.
Before it gets too low the switch turns on again and current flows into
the motor and it's voltage starts building up again.
Now on the battery side of the switch what you see is a huge current
draw, and then nothing, and then huge current, etc.
This current is equal to the current in the motor (you see that right?)
The input capacitors charge up to the battery voltage and try to keep
the voltage stable. They do this by sourcing current when the demand
quickly jumps up and drawing current from the batteries (to recharge
their voltage) when the load drops off. The net result is that they
even out the current that appears at the batteries.
So the large current spikes get sourced by the capacitors and the
battery sees a current that is equal to the time averaged current going
through the switch. In other words if the switch is passing 100 amps
when it is on and zero amps when it is off and it is on 50% of the time,
then the filter caps make this look to the batteries like a constant 50
amps draw.
The, motor on the other hand, is seeing 100 amps but the voltage across
it is only about 1/2 the batteries voltage. This is because the switch
is only turned on half the time so it's voltage never gets to build up
to full pack voltage.
The net result is that power out(volts x amps) = power in minus losses.
The losses are because none of the components are perfect. We lose a
little power in each of them, from the capacitor to the diode.
If you change the duty cycle to 25% on, then the motor voltage is only
25% of the pack voltage. The difference between the two voltages is
higher so when the switch turns on a higher current tries to flow. Net
result is that current in the motor is almost four times what the
batteries see.
If you look at the motor voltage with an O-scope, you will see a DC
voltage with a small AC sawtooth on top. This saw tooth is the voltage
charging up and decaying when the switch turns on and off.
If you measure the voltage on the input side of the capacitors you will
see a DC voltage with a small saw tooth on it. This saw tooth is caused
by the capacitors charging and discharging. Measuring the current here
you will see a DC current with a saw tooth (the capacitor isn't
perfect).
Measure the current at the switch and you will see an on/off current at
what ever duty cycle the controller is running at.
Everybody is happy (except Garry) the laws of physics are intact, and
everything operates they way it is supposed to according to accepted
electronics theory.
> I'm still trying to understand how the PWM controller acts as a DC
> transformer ( using the DC to DC Buck converter principle?) to put all
> those extra electron to the motor. Are there any good tutorial type
> references about this? Thanks,
>
--- End Message ---
--- Begin Message ---
If you accept that power out of the battery into the controller is equal to
power out of the controller into the motor, ignoring efficiency.
Then Vin * Cin = Vout * Cout.
Vin = battery voltage
Vout = battery voltage that has been chopped up by the PWM and is basically
Vin * the percentage of ON time.
So if PWM is at 20% ON time then
Vout = Vin * 0.2
Then Vin * Cin = (Vin * 0.2) * Cout
or
Cout = (Vin * Cin)/(Vin * 0.2)
simplifies to
Cout = 5 * Cin
Andre' B. andre-at-usermail.com
If something cannot be defined, it does not exist.
Isaac Newton
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Mark Thomasson
Sent: Thursday, March 27, 2003 4:01 PM
To: [EMAIL PROTECTED]
Subject: Re: AC controllers
Lee, Excellent circuit! You accomplish the same thing as the original with
only 5 instead of 9 contactor coils, plus getting built in protection
against shorted batteries from welded contacts, a significant improvement.
Interestingly, there are still 9 contacts. We could drop one contact by
making one of the SPDT's into two SPST's, and dropping K5. But then we
would need more mechanical or electrical interlocking to prevent the shorted
battery problem again. The seven step circuit could be done with only 4
contactors (2 less than the original). All I need now is a separately
excited motor designed for high starting torque.
I'm still trying to understand how the PWM controller acts as a DC
transformer ( using the DC to DC Buck converter principle?) to put all
those extra electron to the motor. Are there any good tutorial type
references about this? Thanks,
Mark T.
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, March 26, 2003 2:26 AM
Subject: Re: AC controllers
> Lee Hart wrote:
.............................................
I'm wondering why you couldn't do your 1-2-4-8 switching with 4
> SPDT contactors like this (view with fixed width font):
> _______
> | | K4
> +__|__ NC O ___________to motor +
> 48v ___ / COM
> | NO O/
> |_______|_________
> |
> _______ |
> | | K3 |
> +__|__ NO O _______|
> 24V ___ / COM
> | NC O/
> |_______|_________
> |
> _______ |
> | | K2 |
> +__|__ NO O _______|
> 12V ___ / COM
> | NC O/
> |_______|_________
> |
> _______ |
> | | K1 |
> +__|__ NO O _______|
> 6V ___ / COM
> | NC O/
> |_______|____________to motor -
>
> This only requires 4 contactors. You can still get any voltage from 0v
> to 90v in 6v steps. No combination of contactors K1-K4 being on/off ever
> shorts any battery.
>
> You might want a 5th contactor (K5) for an all-off condition (as shown,
> when K1-K4 are all off they short the motor, which would brake it to a
> stop).
>
> The contactors could all be SPST if the NC-COM contact were replaced
> with diodes. You couldn't do regen with the diodes, however.
>
....................................
> --
> Lee A. Hart Ring the bells that still can ring
> 814 8th Ave. N. Forget your perfect offering
> Sartell, MN 56377 USA There is a crack in everything
> leeahart_at_earthlink.net That's how the light gets in - Leonard Cohen
>
--- End Message ---
--- Begin Message ---
Wow!
I wish I'd a said like Pete did!
Good Job.
Stay Charged!
Hump
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--- Begin Message ---
Aside from building your own off a moped frame it seems that the Morad 1500
is the best buy for performance and price. Anybody have a better idea?
Lawrence Rhodes...
----- Original Message -----
From: "Christopher Zach" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, March 27, 2003 7:30 AM
Subject: Looking for a scooter
> Hi!
>
> Question: I'm thinking about buying an electric scooter. I have looked on
> Ebay, and there are a lot of models, from tiny things up to almost mopeds.
>
> I'd like one with lights/real wheels/reasonable motor/good quality. I
weigh
> 210 pounds. Range can be variable.
>
> Any thoughts on good quality ones? I am sure there is a lot of "junk" out
> there as well...
>
> Chris
>
--- End Message ---
--- Begin Message ---
The covers on the Curtis ends come off easy. The 6 screws on the bottom is
a problem. The rubber ends also seem to be glued in. Anyone know how to
disassemble a Curtis controller? Lawrence Rhodes....
--- End Message ---
--- Begin Message ---
http://www.evworld.com/databases/storybuilder.cfm?storyid=441
--- End Message ---
--- Begin Message ---
Hi folks,
I am just back from a major cross country drive, Portland, Oregon to Kansas
City, Missouri. Along the way I was pleased to see several green power
sites, including hydroelectric sites in Oregon, and wind farms in Wyoming
and Nebraska. Here and there a few private solar arrays were seen. Every
single electric road construction warning sign (those trailer mounted
things) was also solar powered.
I am happy to report that all the wind power sites I saw were in
operation. Out of about 30 plants in one farm in Wyoming I only saw two
shut down, I am guessing for some kind of maintenance.
All this "green power" made me feel even more guilty, as the rental moving
van I was driving was going through fuel at a disgusting rate, from as low
as 9 mpg to a peak of 12.5 mpg.
Thanks,
Mike Chancey,
'88 Civic EV
'95 Force EV (x2)
Kansas City, Missouri
EV List Photo Album at: http://evalbum.com
My Electric Car at: http://www.geocities.com/electric_honda
Mid-America EAA chapter at: http://maeaa.org
Join the EV List at: http://www.madkatz.com/ev/evlist.html
--- End Message ---
--- Begin Message ---
Lawrence Rhodes wrote:
-----------------------------------------
The covers on the Curtis ends come off easy. The 6 screws on the bottom is
a problem. The rubber ends also seem to be glued in. Anyone know how to
disassemble a Curtis controller? Lawrence Rhodes....
------------------------------------------
First, remove the screws in the bottom of the case. (you may have to drill
the heads off the screws)
Softening the potting compound is easily accomplished by immersion in
boiling water (the end with the bus bars on it), dig the softened compound
out with a small screwdriver or similar tool.
May require repeated immersions to keep compound soft.
When enough compound is removed, the entire controller should slide out of
the case.
Roy LeMeur Seattle 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
_________________________________________________________________
The new MSN 8: smart spam protection and 2 months FREE*
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--- Begin Message ---
Hi all you cord wranglers out there,
It is possible to coil a cord (or garden hose, network cables, whatever) so that it
doesn't get twists in it.
The guy that taught me to do it called it coiling over and under.
Below is my attempt to describe how to do it. If it makes no sense at all, go and talk
to a musician, sound engineer or roadie - they are usually very particular about how
their cables are coiled, and should use a similar method to do their coiling.
Start by holding the end of the cord in your right hand (palm up - thumb pointing
away) with the plug towards you.
The first coil is a standard coil (over). Just make a loop about 1ft in diameter and
hold on to it with right hand, next to the plug.
The second coil is the tricky bit. Make a loop the same as you did for the first, but
then give the cord a 360 degree twist so that the remaining cord now comes out between
the two loops instead of at the left hand side of the two loops.
(I wish I had a digital camera or something to show this bit)
Basically you now just repeat these two different coils. Standard (over) and twisted
under.
With a bit of practice, its almost as fast as coiling cords over your forearm.
The net result is that the twists of the over and under coils cancel each other out.
Mark
-----Original Message-----
From: 1sclunn [mailto:[EMAIL PROTECTED]
Sent: Friday, 28 March 2003 4:28 AM
To: [EMAIL PROTECTED]
Subject: Re: That time of the year again...
...
>
> The cord. Someone showed me how to deal with the cord. Run the cord up
> one arm, over the neck, down the other arm. That keeps the cord right
> at your hand should you need to move it around and gives you tactile
> feedback about what the cord may be doing. Mow back and forth and
> always turn away from the power source.
...
2. after many winding and un winding the cord gets twist in it . ////// I
have no solution for this one but think there must be a way to wind the cord
back up and take the twist out .
...
Steve Clunn.
--- End Message ---
--- Begin Message ---
When I had my unit repaired by Curtis, I was told that they charge $50 extra if the
unit has been opened. Mine was but the didn't charge extra.
Steve
In a message dated 3/27/2003 7:40:14 PM Eastern Standard Time, "Roy LeMeur" <[EMAIL
PROTECTED]> writes:
>Lawrence Rhodes wrote:
>-----------------------------------------
>The covers on the Curtis ends come off easy. The 6 screws on the bottom is
>a problem. The rubber ends also seem to be glued in. Anyone know how to
>disassemble a Curtis controller? Lawrence Rhodes....
>------------------------------------------
>
>First, remove the screws in the bottom of the case. (you may have to drill
>the heads off the screws)
>
>Softening the potting compound is easily accomplished by immersion in
>boiling water (the end with the bus bars on it), dig the softened compound
>out with a small screwdriver or similar tool.
>
>May require repeated immersions to keep compound soft.
>
>When enough compound is removed, the entire controller should slide out of
>the case.
>
>
>
>
>
>
>Roy LeMeur �Seattle 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
>
>
>
>
>_________________________________________________________________
>The new MSN 8: smart spam protection and 2 months FREE* �
>http://join.msn.com/?page=features/junkmail
>
>
--- End Message ---
--- Begin Message ---
The cable coiling technique that I learned while rock climbing
and coiling climbing ropes is quick, easy, and keeps the cords from
getting tangled.
You let the plug hang from your hand a couple feet or so.
>From there you hang a loop out the opposite side of your hand that
is the same length. The next loop hangs on the plug side, then back
to the other side. You make hanging loops on opposite sides until you
start nearing the end of the cord. You then wrap the cord around
both sets of loops, under your hand, binding the whole package neatly
together. A final loop of cord can be pushed through the loop where
your hand was, then the end can be tucked through that loop and
cinched tight.
There's now a nice loop to hang it from the wall, or you can
throw it in a pile of cords and not have it come unraveled. I've never
had a cord get tangled when it was wound this way.
...John
--- End Message ---
--- Begin Message ---
[EMAIL PROTECTED] wrote:
> The ones here are designed to operate at 15 rpm. Quite often they
> appear idle but I believe they are not.
They were absolutely, totally motionless. Despite sufficient breeze to
keep flags flying, etc.
--
Lee A. Hart Ring the bells that still can ring
814 8th Ave. N. Forget your perfect offering
Sartell, MN 56377 USA There is a crack in everything
leeahart_at_earthlink.net That's how the light gets in - Leonard Cohen
--- End Message ---
--- Begin Message ---
The covers on the Curtis ends come off easy. The 6 screws on the bottom is
a problem. The rubber ends also seem to be glued in. Anyone know how to
disassemble a Curtis controller? Lawrence Rhodes....
See my article on modifying one, it mentions how to disassemble them.
http://CafeElectric.com/curtis/regen/index.html
The first step in modifying my controller was to remove the
potting compound from the end and the screws on the bottom. To
do this, I put the controller in a large pot of boiling water until it
was hot. This softens the potting compound. I used a nail (any
sharp object will do) to remove the potting material from the
location of the six screws in the bottom and removed these
screws. The potting compound on the terminal end can be broken
free from the case with a punch and a hammer. By tapping the
potting carefully around the edge where it sticks to the aluminum,
I broke this seal. I removed the electronics from the case by
putting a screwdriver through the M- and A2 terminals and
pulling. The heat sink and mounted electronics slid out. I
removed the rest of the potting compound from the terminals
with pliers. I saved the foam piece for the re-potting process.
-Otmar-
http://www.CafeElectric.com
Mailto:[EMAIL PROTECTED]
--- End Message ---
--- Begin Message ---
http://www.qsl.net/w8rnh/EVT100.jpg
I just posted this on a robot power group for people
that use power semiconductor H bridges for reversing.
They were interested in contactor/relay control of
the series field, but I thought the diagram would be
of interest for those that have considered regen control
on a series wound motor. This is shown in the elementary, but
as Otmar has described this setup does not yield big range extension
for an on road EV with a series wound motor.
Rod
--- End Message ---
--- Begin Message ---
Garry Stanley wrote:
> Please excuse my ignorance, but where, in here, is the Lenz counter
> to direction of motion force, that is generated when ever a magnet
> and a coil come into proximity, hidden.
Lentz's law states, "The direction of an induced CURRENT is such as to
oppose the cause producing it." It is discussing current, not voltage.
> I have heard it called back emf which I tend to use, but everyone
> says it's not and I have heard it referred to as eddy currents.
Eddy currents are something else again. You are getting voltages and
currents confused again.
Being a current, eddy currents *do* cause heating, and so are a source
of loss in a motor.
--
Lee A. Hart Ring the bells that still can ring
814 8th Ave. N. Forget your perfect offering
Sartell, MN 56377 USA There is a crack in everything
leeahart_at_earthlink.net That's how the light gets in - Leonard Cohen
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EVLN(Pitzer president plugs-in)
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http://www.dailybulletin.com/Stories/0,1413,203~21481~1272898,00.html
Article Published: Wednesday, March 26, 2003 - 5:26:58 PM
College president gets an electric car as gift
CLAREMONT -The Eco Center at Pitzer College, in an effort to
promote sustainable energy practices, donated an electric
vehicle to new President Laura Skandera Trombley Wednesday.
The Center purchased the vehicle with student allocated
funds as a gift to the new president.
"We wanted to help welcome her into the Pitzer community,"
said student and Eco Center representative Phillip Thompson.
"The president's use of the vehicle also will serve as a
reminder to continue implementing sustainable energy
practices at Pitzer."
The car, a four-seater Global Electric Motorcar made by
Chrysler, was purchased for about $4,300.
- Mira Katz, (909) 483-8551
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EVLN(State considers abandoning EVs for fuel vehicles)
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http://www.mlive.com/newsflash/regional/index.ssf?/newsflash/get_story.ssf?/cgi-free/getstory_ssf.cgi?g9001_BC_MI--ZeroEmissions&&news&newsflash-michigan
State considers abandoning electric car for newer technology
By BRIAN MELLEY The Associated Press 3/27/03 11:17 PM
SACRAMENTO (AP) -- California's trailblazing effort to put
drivers behind the wheels of battery-powered cars was nearly
out of juice Thursday.
The Air Resources Board considered whether to abandon the
electric car in support of promising low-pollution
gas-powered autos, as well as the fuel cell vehicle, a move
that would lend strong regulatory support to a technology
that's being touted as the engine of the future.
The vote expected Friday comes after a fervent fight from
environmentalists, electric car drivers, engineers and
observers who supported the state's 1990 landmark regulation
that has driven technological changes in the auto world.
California Power Authority Chairman David Freeman, who said
he has followed the progress of alternative-fuel cars for 25
years, thinks the air board staff has been swayed by
automakers to ditch the quest for the pollution-free
vehicle. He said it was time to "catch the falling flag."
"We are now worshipping at the altar of the craven image of
the fuel cell," Freeman said. "Y'all are smarter and better
than you think you are. You've just had too much time with
the auto industry."
Nearly two-thirds of the 79 speakers signed up to testify
about the rule were expected to oppose the rewritten
regulation, while only five were in favor. Automakers, who
are opposed to any regulation and want innovation to be
driven by consumer demand and competition, were among the
roughly one-third that remained neutral on the proposal.
Representing Honda, Ben Knight said technology not
envisioned when the rule was passed in 1990 had produced
startling results approaching 100 percent control of
emissions in gas-powered cars.
"This is the most effective path in improving air quality,"
Knight said.
While the state has continuously weakened the regulation
that would have required automakers to sell 10 percent, or
about 100,000, pollution-free cars in the state this year,
the proposed rule would abandon that goal for 250 fuel cells
vehicles by 2008. It would replace that quota with higher
numbers of low emission gasoline-powered cars and
increasingly popular hybrids that run on a combination of
gas and electricity.
One of the chief concerns is that the proposed new
requirements do not require any nonpolluting vehicles to be
produced after 2009, leaving that number to be set later. In
the past, the board set quotas and then whittled them down
as the industry fought back.
"I am very interested in the numbers in the end game here,"
said board member Matthew McKinnon. "I think we're asking
for worse than the trouble we've had here along the way."
Automakers resisted building a quota of battery-powered cars
that were expensive and generally didn't travel more than
100 miles without a three- to six-hour charge. But critics
claim the auto industry never made a serious attempt to make
the cars attractive to buyers or to improve the technology.
Last year, a federal judge in Fresno put the quota on hold,
prompting the board to rewrite the rule.
Air board staffers said the revisions were aimed at
reflecting the limits of battery-powered cars and the
promise of the fuel cell, which has been hailed by both car
makers and the White House. Fuel cells produce electric
power from a chemical reaction between oxygen and hydrogen
that only emits clean water from tailpipes.
"We are not backing down," board Chairman Alan Lloyd said
about the quest for requiring the so-called zero-emission
vehicles. "It is important to get to zero as fast as
possible."
Still, a group of die-hard electric car supporters were not
convinced that the rewritten rule would achieve that goal.
A caravan of electric cars left Vacaville in the morning and
ringed the parking spaces around the state's Environmental
Protection Agency building.
They applauded when board members spoke in favor of the
technology that powers their silent, purring engines.
"I am not ready to close the door on that technology," said
board member Dorene D'Adamo to the audience's resounding
approval. "I'm real nervous about abandoning a technology
that has continued to progress."
On the Net: California Air Resources Board:
http://www.arb.ca.gov Copyright 2003 Associated Press. All
rights reserved.
===
State considers abandoning electric car for newer technology
MLive.com, MI - 1 hour ago ... The Air Resources Board
considered whether to abandon the electric car in support of
promising low-pollution gas-powered autos, as well as the
fuel cell vehicle ...
State considers abandoning electric car for newer technology
Kansas City Star, MO - 1 hour ago The Air Resources Board
considered whether to abandon the electric car in support of
promising low-pollution gas-powered autos, as well as the
fuel cell vehicle ...
State considers abandoning electric car for newer technology
Miami Herald, FL - 1 hour ago The Air Resources Board
considered whether to abandon the electric car in support of
promising low-pollution gas-powered autos, as well as the
fuel cell vehicle ...
State considers abandoning electric car for newer technology
Wichita Eagle, KS - 1 hour ago The Air Resources Board
considered whether to abandon the electric car in support of
promising low-pollution gas-powered autos, as well as the
fuel cell vehicle ...
State considers abandoning electric car for newer technology
Press-Enterprise, CA - 1 hour ago ... The Air Resources
Board considered whether to abandon the electric car in
support of promising low-pollution gas-powered autos, as
well as the fuel cell vehicle ...
State considers abandoning electric car for newer technology
Press-Enterprise, CA - 5 hours ago ... The Air Resources
Board considered whether to abandon the electric car in
support of more promising low-pollution gas-powered autos
and the fuel cell vehicle ...
State considers abandoning electric car for newer technology
San Jose Mercury News, CA - 5 hours ago The Air Resources
Board considered whether to abandon the electric car in
support of more promising low-pollution gas-powered autos
and the fuel cell vehicle ...
State considers abandoning electric car for newer technology
Sarasota Herald-Tribune, FL - 5 hours ago ... The Air
Resources Board considered whether to abandon the electric
car in support of more promising low-pollution gas-powered
autos and the fuel cell vehicle ...
-
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--- Begin Message ---
EVLN(Sadly, this is not how automobile manufacturers think)
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http://www.dailytrojan.com/article.do?issue=/V148/N41&id=03-emis.41v.html
Student Newspaper of the Universitiy Southern California
Dara Purvis
Emissions policies choking Los Angeles
[Comic image] Mike Salvato I Daily Trojan
As much as the Bush Team would love to draw all our
attention to the "shock and awe" of the first strike, there
are other issues going on in the world � even in California,
that bastion of hippies and crazy liberals.
In 1990, far-thinking legislators in California decided that
sooner was better than later when attempting to combat air
pollution, a problem all residents of Los Angeles know a
little something about (cough). The California Air Resources
board adopted rules attempting to spur production of
energy-efficient cars, requiring 10 percent of all vehicles
sold in California in 2003 to be emissions-free.
Naturally, this provoked much outcry from automobile
manufacturers. Now, it is true that consumer demand for a
certain type of vehicle cannot be created by government
fiat. When the auto industry wants to create demand for a
useless but profitable vehicle, they hire a rock band and
drape scantily-clad models around it. It is hard to sell the
"sizzle" of an electric car. But it is also true that
consumers won't buy something that they don't know exists,
or that they can't find.
Government officials trying to reduce the poisons we breathe
believed that making environmentally-friendly cars available
would spur demand, in part because a potential for such
demand already exists. There have always been a small number
of committed environmentalists that will go to any length
necessary to buy the products they desire. For example, Ed
Begley Jr. drives a car he modified into an electric vehicle
himself, and years ago converted his house so that it was
entirely solar-powered. Obviously the average Californian
does not have that level of passion. But there are large
numbers of opportunistically-conscientious citizens. Most
people will not separate their garbage and drive it off to a
recycling center, but if the city gives them a couple of
bins in which to discard paper and cans, they will. It thus
seems a fair assumption that, presented with the opportunity
to buy either a gas-guzzling car or a more responsible (and
cheaper, in the long run) no-emissions vehicle, a large
number of people will choose the car that pollutes less.
This assumption has proven true as to hybrid vehicles. In
the past year, commercials for cars that are powered by a
mixture of gas and electricity have actually been on
television, as manufacturers decided to give marketing a
chance � and demand shot through the roof. Sales of hybrid
vehicles increased by 50 percent last year, an unheard-of
leap especially for sales of new cars in questionable
economic times, and for the Prius (the most popular), demand
has exceeded supply.
Purchasing totally electric vehicles is indeed a greater
step for consumers to make � given our society's marriage to
gasoline, a new perspective might take some getting used to.
But the advantages of reducing or eliminating our dependence
on foreign sources for oil and the concomitant decrease in
production of incredibly harmful pollutants are
innumerable.
Sadly, this is not how automobile manufacturers think. After
the 1990 rules were put into effect, giving the auto
industry 13 years to sell 100,000 electric cars in a state
of 34 million residents, automakers whined, protested,
dragged their heels and finally sued in their attempts to
continue building inefficient, environmentally disastrous
cars. (Turns out lawyers are all as evil as the Republicans
would have you believe when they are pushing elimination of
medical malpractice liability.)
It appears that their despicable tactics have won. Tomorrow,
the California Air Resources board is expected to lower its
requirements. Most likely, the requirement on sales of
vehicles will shift to 4 percent of sales being hybrid cars,
and a further 6 percent gasoline-powered autos that already
have lower emissions, such as the Honda Accord or Toyota
Camry. A mere 250 cars must be produced that are
no-emission.
If all that were at issue here were obscenely inflated
profits, the rape of the natural environment, and the
continuing necessity for the U.S. military to be used as an
instrument of corporate energy policy, it would be almost
understandable that the hacking, wheezing, choking denizens
of southern California and of the Central Valley would put
their children into the SUV and drive them to the asthma
clinic, never once wondering why Johnny can't breathe. But
battery-powered electrical vehicles could be driving down
the 110 freeway right now, and we would all be inhaling less
poison, if the decisions made by our democratically elected
and appointed officials had not been sabotaged by Big Oil
with Big Money.
A lot of you and your children are going to die sooner than
you would have, in greater pain, because Corporate
Auto-America would rather stick with the Hummers it knows
will bring even more money to higher-paid CEOs. Take a deep
breath, Angelenos � that acrid stench that makes you wheeze
it back out is your health being burned on the altar of
greed and stupidity.
Editorial columnist Dara Purvis is a senior majoring in
political science. To comment on this article, call (213)
740-5665 or e-mail [EMAIL PROTECTED] Copyright 2003 by the
Daily Trojan. All rights reserved. This article was
published in Vol. 148, No. 41 (Wednesday, March 26, 2003),
on page 6.
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