EV Digest 4998
Topics covered in this issue include:
1) Re: links on evproduction.org wiki
by David Dymaxion <[EMAIL PROTECTED]>
2) Re: I found some information on GE EV-1 Controller, but details lacking
(long)
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
3) Re: I found some information on GE EV-1 Controller, but details lacking
(long)
by Danny Miller <[EMAIL PROTECTED]>
4) RE: Are these chargers any different?g
by "Don Cameron" <[EMAIL PROTECTED]>
5) RE: [BAYESIAN SPAM] - Re: Required horsepower - Bayesian Filter detected
spam
by "Peter May" <[EMAIL PROTECTED]>
6) Motor on e-bay - 8 inch diametetr x 15.5 inches length - $30 + shipping
by [EMAIL PROTECTED]
7) RE: CVT transmission for EV - long
by "Dewey, Jody R ATC (CVN75 IM3)" <[EMAIL PROTECTED]>
8) Re: Cushman's available & stability question
by "slodown27" <[EMAIL PROTECTED]>
9) Re: Motor control for direct drive setup
by "Paul G." <[EMAIL PROTECTED]>
10) Re: general questions re max for E-Tec
by "Philippe Borges" <[EMAIL PROTECTED]>
11) Re: CVT transmission
by Jeff Shanab <[EMAIL PROTECTED]>
12) Re: Setting up a Direct Drive
by Jeff Shanab <[EMAIL PROTECTED]>
13) Re: links on evproduction.org wiki
by "Michaela Merz" <[EMAIL PROTECTED]>
14) Re: Setting up a Direct Drive
by Jim Coate <[EMAIL PROTECTED]>
15) Re: Required horsepower
by "STEVE CLUNN" <[EMAIL PROTECTED]>
--- Begin Message ---
I have been a member of both EAAs (Experimental Aircraft Association
and the electric one). The airplane EAA is a remarkably successful
organization.
Anyone, some educated guesses here:
Pilots are used to lots of bureaucracy and paperwork, and
therefore might be more used to working with the system.
Pilots are a wealthy demographic. For instance, when I was
subscribed to pilot magazines I got an offer for a million dollar
line of credit! I would also get offers for other rich person's kinds
of things. These offers quit appearing in my mail when I quit getting
the magazines.
Several kitplane makers are doing very well.
--- Victor Tikhonov <[EMAIL PROTECTED]> wrote:
> Naturally, question then becomes why don't we have lobby
> as ARRL or especially EAA does. What's the fundamental difference
> between EV and Aircraft?
>
> Perhaps, partly because amateur built cars share the road with
> others and subject them to "unregulated" (so dangerous
> in the eyes of authorities) vehicles, possibly public complaints,
> etc. With an aircraft your failure is your only own problem
> (unless you crash into a residential area, but the available
> space for flying is regulated as well).
>
> Other reasons?..
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
Here is some advice that Lee Hart gave me through a few reply on the list.
Basically he said to parallel capacitors very close to the battery input to
the controller. I'm going to use 4,400uf in ten caps. Lawrence Rhodes....
Lawrence Rhodes wrote:
I have an SCR based controller in the Electravan that switches
at 1500 hz with inadequate filtering on the battery side.
Is it possible that the battery sees high current pulses and
behaves more like it is discharging at 1000 amps than 100 and
consequently has much less capacity.
Yes, it is possible; even probable. You can measure the battery ripple
current with a multimeter. Measure across your battery current shunt, or
pick two spots along one of the wires from your batteries to the
controller. For example, the positive terminal of the battery and the
other end of that wire that connects to the controller. The voltage drop
in this wire is proportional to current.
Connect wires from these points to your multimeter, and go for a drive.
While cruising at some constant speed, measure the DC voltage and the AC
voltage. Their ratio is the percent ripple current. If the AC voltage is
more than about 10% of the DC voltage, then your batteries would benefit
from the addition of filter capacitors.
These old SCR controllers usually didn't have a large input filter
capacitor bank. There were several reasons.
First, they expected them to be used with huge forklift batteries, which
already have lots of capacitance (a "mere" 1000 amp load for these
batteries isn't a high rate :-) They may not have been aware that lack
of capacitors would be a problem for lower-capacity higher-resistance
batteries.
Or they knew, but were concerned about the reliability of electrolytic
capacitors. Modern electrolytics are merely bad -- back then they were
even worse! Note that a 20-year-old SCR controller still works; if they
had used electrolytics, it wouldn't!
Or, they knew and just wanted to save money.
You can add the filter capacitors yourself. You need to connect them as
close to the controller's input as you can, with as short and heavy a
wire as possible.
We don't have enough data to calculate a value, but it's going to take
thousands of microfarads. If it were me, I'd look for some surplus
electrolytics intended for switching power supply filtering, and put in
1,000uf worth. Measure your ripple current again, and see how much it
dropped. Then you can guess how much more it will take.
--
Ring the bells that you can ring
Forget your perfect offering
There is a crack in everything
That's how the light gets in
-- Leonard Cohen, from "Anthem"
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
Lawrence Rhodes wrote:
I have a 120v 20 battery pack. Weighs 1400 pounds. Lee recommended
1000uf and check again. What is the problem of putting in a few
thousand?
No direct harm; the more, the merrier.
However, the goal here is to reduce the battery ripple current. With
perfect zero-resistance capacitors, 1000uF is plenty because almost all
the controller's ripple current will then flow in the capacitors, not
the batteries.
However, real capacitors also have resistance, called ESR on the data
sheets (Equivalent Series Resistance). Capacitor ESR diverts ripple
current back to the batteries. ESR also produces heat, making the
capacitors get hot. It ultimately determines the maximum ripple current
that the capacitor can stand without overheating.
So, your goal is a capacitor with:
a. At least 1000uF of capacitance.
b. An ESR at least as low as your batteries ESR.
For example, an Optima has an ESR of about 0.003 ohms.
A pack of 10 has a total ESR of 10x0.003 = 0.03 ohms.
Add 20 connections at 0.001 ohm each = 0.05 ohms total.
So you want a capacitor with an ESR of 0.05 ohms or less.
c. A ripple current rating of at least 1/4th your motor current.
400 amp motor current means the controller is switching between
0 and 400, which is +/-200 amps peak AC ripple, which is about
100 amps RMS.
What you'll find is that its easy to find a 1000uF electrolytic
capacitor; but its ESR will be 1 ohm and its ripple current rating is
only 5 amps. Just one provides the capacitance, but you'd need 20 of
them in parallel to satisfy the ESR and ripple current requirements.
This is what you see in many controllers; a large number of cheaper
electrolytics, with far more capacitance than needed just to get the
ripple and ESR ratings.
Or, oil-filled paper or polypropylene film capacitors can easily meet
the ESR and ripple current requirements; but their capacitance is low. A
big metal can oil-filled capacitor can have 20uF of capacitance, 0.1 ohm
ESR, and a 25-amp ripple current rating. You'd need only 4 of them for
ESR and ripple, but 50 to get the capacitance. These capacitors would be
a lot larger and more expensive than electrolytics. So what you see in
some controllers are a smaller number of electrolytics (just to get the
capacitance), in parallel with a smaller number of oil or film
capacitors (to get the ESR and ripple ratings).
That's why I suggested that you experiment.
--
Ring the bells that you can ring
Forget your perfect offering
There is a crack in everything
That's how the light gets in
-- Leonard Cohen, from "Anthem"
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart
Lawrence Rhodes wrote:
Lee I hop I'm not bothering you too much but I didn't want to blow
anything up.
Aw, you're no fun! You should always have kids around when you blow up
capacitors. They enjoy the pyrotechnics. :-)
When you get an electrolytic capacitor that has been sitting unused for
a long time, you have to re-form its dielectric. Connect it to a high
voltage power source (like 150 vdc) with a resistor in series to limit
the current to no more than a few milliamps (like 100k ohms). Let it sit
until the capacitor voltage stops rising -- it will take 1-24 hours
depending on how long they have sat. If a capacitor won't rise to its
rated voltage without drawing more than 1 ma, consider it "bad".
You can also estimate their real capacitance at the same time. R x C is
the time constant -- the time it should take to charge to 2/3rds of the
applied voltage. 440uf x 100k = 44 seconds, so it should take 44 seconds
to charge to 2/3 * 150v = 100v. This will also weed out any bad ones.
These are the silver ones General Electric 92F311AMMA, 440UF -10+50%,
150vdc 200v surge, 85C Max Ambient. I got 10 of these. Should I put
them all on the positive or negative side or split them on each leg?
Do I have enough?
Put all of them in parallel, + to +, - to -. Since you're after the
lowest resistance, the usual method is to get two flat strips of copper
bus bar, drill holes for the capacitor's screws, and screw them to the
bar.
You connect the resulting "big" capacitor directly across the
controller's battery + and - inputs. Again, this should be done with
short, heavy wire or bus bars. If you don't have a precharge resistor,
you should add one; if the main contactor closes and tries to charge all
of these capacitors instantly, it will be murder on the contacts.
I described a method to find out how much/many capacitance is needed
based on the ripple current. Too few capacitors, and they will get hot
and not do much good. More is always better, but you reach a point where
the extra cost and weight isn't worth the slight improvement.
--
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
Lawrence Rhodes wrote:
So I put the plus buss bar on the positive end of the big capacitor
and the neg end of the big capacitor on the neg side of the pack.
Now I have the caps in parallel with the pack. Won't they just
charge by themselves now?
The capacitors connect directly across the CONTROLLER's B+ and B-
inputs, with the shortest fattest possible leads. The controller draws
pulses of current, and we want these pulses to come from the capacitors,
not the batteries.
I assume you have contactors, fuses, circuit breakers, a big disconnect
switch, or SOMETHING between the batteries and controller. That means
there will be times that one or more of these is open. When you close
it, the capacitors will try to charge INSTANTLY, leading to huge
currents which will damage the contacts of the last device to close. The
precharge resistor is intended to slowly charge the capacitors over a
second or two; then close the last switch.
like the air pocket used in water system to stop the pipes from
vibrating which I guess is what ripple current is.
Yes, it is basically the same thing that plumbers call "water hammer".
I'll try 10 caps and check for heat. Then I'll add more. I'll also
try weeding out the caps by charging with a variac.
...and a diode! Remember these are DC capacitors!
--
Humanity is acquiring all the right technology for all the wrong
reasons.
-- R. Buckminster Fuller
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
----- Original Message -----
From: <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, December 15, 2005 5:51 PM
Subject: I found some information on GE EV-1 Controller, but details lacking
(long)
The references date back to 1999. Some excerpts are below. Essentially,
what I am trying to do is up the amp rating of the controller, and it
looks like
I may also need to add caps to smooth out the ripples so I don't kill the
batteries. Has anyone successfully done this - increase the power rating
and
improve battery life. I don't want to reinvent the wheel or burn up a
bunch of
old controllers if someone has already figured this out and made it work.
Remember, I am not a EE, so I need a pretty basic straightforward
explanation
that a Mechanical Engineer can understand. Something like parallel the
SCRs
and add X number of Y rated caps between these terminals. Hopefully, it
is
that easy. But if it isn't, I'll try to follow the explanation. FYI. I
did
have one of these in one of my old cars that pulled more than 500 A on
acceleration ... not sure how it was done though.
Exerts from 1999 below.
Thanks,
Steve
Ev Archive for October 1999
1670 messages, last added Wed Aug 08 18:46:38 2001
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[Date Index][Thread Index]
RE: EV-1 SCR controller question
------------------------------------------------------------------------------
--
To: "'[email protected]'" <[email protected]>
Subject: RE: EV-1 SCR controller question
From: Glubrecht Dale D <[EMAIL PROTECTED]>
Date: Thu, 21 Oct 1999 08:15:56 -0500
Reply-To: [email protected]
Sender: [EMAIL PROTECTED]
------------------------------------------------------------------------------
--
I have run the regular EV-1 controller and my monster EV-1 controller on a
80uH, 12", 12 brush, <0.016 resistance at stall, motor. The motor would
hit
3000A on a 48V forktruck battery. I had current zero crossings and huge
peak
currents when this controller and motor combination ran at a duty cycle.
The
little EV-1(standard) would undervoltage cutout on a small hill after a
few
thousand feet of road passed under the car. The big 1000 amp monster took
7-14 miles with the same 95A.H. bats. I figured that the little one didn't
like the voltage ripple. I did not put any filter caps on it because I did
not have that many caps even at $.50/ripple amp. IF the controller was on
for 2ms at stall the current would come near 2000A every cycle. The
battery
plates would howl at the PWM freq. while the big nasty motor would be near
silent. These controllers were not meant to be nice to batteries. A big
load
inductance helps as does a highly capacitive source.
If I could drive that car in full on mode (65 in second gear) I would have
gotten much better range then 14 miles. That was the whole problem, the
high
current peaks sucked the batteries at a very ugly rate. Part throttle
operation was bad for range. When I just changed to my IGBT 15kHz
controller
it doubled the range.
They are a very reliable controller, they have to be. This particular
controller ran in a aluminum smelting plant (Kaiser AL in Spokane WA) and
ran for a full life. It did not seem like any parts blew until I ran it in
my car. It locked on full power and I had a wonderful ride. (1600A when
shifting.) This is their death mode. They just do not commutate off. A Big
contactor is a must or one just hits the clutch and a short time later
drops
the contactor. Somebody may want to correct me but all of the components
on
the power board are long life. When you add lytic's things go down hill.
They are also a very efficient controller because they all have the bypass
contactor outputs built in. I would think that one could use a foot bypass
switch instead of the built in bypass circuit. The built in circuit will
not
let the motor exceed the preset current. I doubt that you will harm the
freewheel diode even with stall current that one gets when engaging bypass
at a stop and go light.
Enjoy your EV-1 controller but keep your foot on or near the clutch when
waiting at a crosswalk.
*****************************
Dale Glubrecht
My Porsche Would Be Zero Emission
But My Tires Keep Smoking...
John Deere WC&CE div.
(919) 567-6587
[EMAIL PROTECTED]
*****************************
-----Original Message-----
From: Eric Chang [SMTP:[EMAIL PROTECTED]
Sent: Wednesday, October 20, 1999 7:32 PM
To: [email protected]
Subject: RE: EV-1 SCR controller question
Hi Roger. It is not guaranteed that there is a series inductor. The
block diagram of the GE EV-1 controller that I have does not have a
series
inductor. If you look inside the box, you will see inductors, but these
are resonant inductors that shut off the secondary SCR which charges the
turn-off capacitor. This is from the diagram in the Jet Electrica
manual.
By the way, this diagram is also slightly flawed. It will not commutate
off. The correct version is shown in the Motorola Thyristor manual.
Another good circuit diagram is in "Convert Your Car to Electric", which
I
already mentioned in a post. There is a detailed diagram, with no series
inductor (only a resonant turn-off inductor). This circuit looks like it
will work.
Be careful.
Eric
--
On 20 Oct 1999 14:20:00 -070 Roger Stockton wrote:
>Hi Lee,
>
...
>the EV-1 controller, so assumed the worst. Are you fairly certain
>about the ballpark value of the inductor? (The example in Brant's
>book resulted in a value of a few hundred mH - unless he slipped
>a few decimal places - and his example seems to be based around
>a GE controller, though not necessarily the EV-1. I suppose I can
...
> -----Original Message-----
>From: [email protected] [SMTP:[EMAIL PROTECTED]
>Sent: Wednesday, October 20, 1999 12:46 PM
>To: [email protected]
>Cc: [EMAIL PROTECTED]
>Subject: Re: EV-1 SCR controller question
>
>[snip]
>
>SCR controllers have another inductor inside the controller; total
>inductance is more like a few hundred uH. This helps. The frequency
>isn't fixed; it varies with load in a way that also helps.
>
...
>Lee A. Hart Ring the bells that you can ring
>4209 France Ave. N. Forget the perfect offering
>Robbinsdale, MN 55422 USA There is a crack in everything
>(612) 533-3226 That's how the light gets in!
><[EMAIL PROTECTED]> Leonard Cohen
>
>
--== Sent via Deja.com http://www.deja.com/ ==--
Share what you know. Learn what you don't.
Ev Archive for October 1999
1670 messages, last added Wed Aug 08 18:46:39 2001
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--
[Date Index][Thread Index]
RE: EV-1 SCR controller question
------------------------------------------------------------------------------
--
To: "'[email protected]'" <[email protected]>
Subject: RE: EV-1 SCR controller question
From: Glubrecht Dale D <[EMAIL PROTECTED]>
Date: Tue, 19 Oct 1999 07:34:16 -0500
Reply-To: [email protected]
Sender: [EMAIL PROTECTED]
------------------------------------------------------------------------------
--
Go down to the local Hyster fork truck dealer/service outlet with your
controller in tow. They may recognize it and sell you the book on it.
I got the book for my 48 V EV-1 version and put the 144V EV-1
control box on top. That made a 1000A @120V controller. It caused the
batteries to hum instead of the motor. (needed Caps) I gave the controller
to my Father for his EV. I have heard rumors of these controllers blowing
at
144V. The SCRs are rated for 200V as I remember. These controllers are
notorious for blowing full on. Have an emergency disconnect or use the
clutch pedal. Sometimes the failure will weld contacts when you try to
break
the circuit so do not depend on the contactor or drop the contactor when
the
motor is wound out.
*****************************
Dale Glubrecht
My Porsche Would Be Zero Emission
But My Tires Keep Smoking...
John Deere WC&CE div.
(919) 567-6587
[EMAIL PROTECTED]
*****************************
-----Original Message-----
From: Roger Stockton [SMTP:[EMAIL PROTECTED]
Sent: Monday, October 18, 1999 7:52 PM
To: [email protected]
Subject: RE: EV-1 SCR controller question
Hi Perry,
The EV-1 controller in my car has a sticker on the side that says it'll
take 84 to 144V nominal. As I understand, the EV-1 is rated for 450
motor
amps, and one guy I know who upgraded to a 400A Curtis 1221 reports that
he has noticed the reduction in power with the Curtis.
If at all possible, verify that the system works before disconnecting
anything; even if the batteries in the car are completely shot, you may
be
able to get them over 84V immediately after charging, and can then verify
that when you turn the key the main contactor pulls in and when you step
on
the accelerator the controller growls and the motor turns. Then
carefully
label all wires so that everything can be reinstalled identically when
the
time comes.
The wiring in my car sounds similar to yours (i.e. most of the wires
running
to/from the controller are the same [grey] colour). At least in my case,
it
looks worse than it really is: several wires simply run from one side of
the
controller to the other and the rest basically run either to the main
contactor
or to the throttle pot/relay assembly.
I'm also considering "recycling" my controller to postpone the cost of
purchasing a modern controller; it will be fed from a 144V string of YTs.
Other than the funky "pedestrian-warning" alert at low speeds (an
advantage),
the main disadvantage of using this controller appears to be its lower
efficiency relative to modern controllers.
What do you have in mind for yours?
Cheers,
Roger.
-----Original Message-----
From: [email protected] [SMTP:[EMAIL PROTECTED]
Sent: Monday, October 18, 1999 1:31 PM
To: Eric Chang
Cc: [EMAIL PROTECTED]; [email protected]
Subject: Re: EV-1 SCR controller question
no im just rying to figure out what its capable of, and if it will suit
my needs. im toying with different voltage battery packs, and i need to
decide first of all if i want to or need to spend the money for a new
controller....plus the original builder wired the whole car really
poorly, ran cables next to sharp edges, used one color wire throught the
whole car, etc...and since i have to restore the car the controller is
getting taken out and i want to make sure i have a wiring diagram of how
it gets hooked up, etc...its the one part of an EV that i dont know
enough about and id like to do some more reading about this model.
im 95 percent sure its working, it was when it wsa parked last time 4-6
yrs ago...but if it wont fulfill the prupose i need its useless to me.
Perry Ellington
--- End Message ---
--- Begin Message ---
Where you gonna get caps rated for that duty though?? This doesn't
sound very practical to me. Most of those caps are rated for a few amps
of ripple. Driving at a higher current will shorten their lives
considerably. And is the ESR low enough to be able to deliver high
current better than the battery itself? If not it has little function
as a filter.
Is it possible to use one of the big toroidal cores to make an inductor
that the cable can be wrapped around? An LC filter would be nice, but
at 1.5KHz the effectiveness of any reasonably sized core seems limited.
Same problem with the caps.
Danny
Lawrence Rhodes wrote:
Here is some advice that Lee Hart gave me through a few reply on the
list. Basically he said to parallel capacitors very close to the
battery input to the controller. I'm going to use 4,400uf in ten
caps. Lawrence Rhodes....
Lawrence Rhodes wrote:
I have an SCR based controller in the Electravan that switches
at 1500 hz with inadequate filtering on the battery side.
Is it possible that the battery sees high current pulses and
behaves more like it is discharging at 1000 amps than 100 and
consequently has much less capacity.
Yes, it is possible; even probable. You can measure the battery ripple
current with a multimeter. Measure across your battery current shunt, or
pick two spots along one of the wires from your batteries to the
controller. For example, the positive terminal of the battery and the
other end of that wire that connects to the controller. The voltage drop
in this wire is proportional to current.
Connect wires from these points to your multimeter, and go for a drive.
While cruising at some constant speed, measure the DC voltage and the AC
voltage. Their ratio is the percent ripple current. If the AC voltage is
more than about 10% of the DC voltage, then your batteries would benefit
from the addition of filter capacitors.
These old SCR controllers usually didn't have a large input filter
capacitor bank. There were several reasons.
First, they expected them to be used with huge forklift batteries, which
already have lots of capacitance (a "mere" 1000 amp load for these
batteries isn't a high rate :-) They may not have been aware that lack
of capacitors would be a problem for lower-capacity higher-resistance
batteries.
Or they knew, but were concerned about the reliability of electrolytic
capacitors. Modern electrolytics are merely bad -- back then they were
even worse! Note that a 20-year-old SCR controller still works; if they
had used electrolytics, it wouldn't!
Or, they knew and just wanted to save money.
You can add the filter capacitors yourself. You need to connect them as
close to the controller's input as you can, with as short and heavy a
wire as possible.
We don't have enough data to calculate a value, but it's going to take
thousands of microfarads. If it were me, I'd look for some surplus
electrolytics intended for switching power supply filtering, and put in
1,000uf worth. Measure your ripple current again, and see how much it
dropped. Then you can guess how much more it will take.
--- End Message ---
--- Begin Message ---
I was assuming that "charge profile" referred to the CC/CV charge profile
graph, that shows voltage/current (Y) and time (X). A change in either
current/voltage or time would constitute a different profile. (at least they
would look different anyways at the same scale).
Is there a formal definition "charge profile" or "charge profile setpoints"?
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 Roger Stockton
Sent: December 15, 2005 9:25 AM
To: [email protected]
Subject: RE: Are these chargers any different?
Don Cameron [mailto:[EMAIL PROTECTED] wrote:
> I would like to know "how" a bettery charger can detect that a battery
> is AGM versus Gel. These two type of batteries have very different
> charging profiles, and if treated the same, one or the other will
> suffer.
Careful here; there is a profound difference between a charge "profile"
and the profile setpoints. Your Interacter charger may use different
profiles for the different battery types, but this does not need to be the
case.
For instance, DEKA's recommended profiles for their AGMs and gel products
are *exactly* the same, however the specific setpoints (voltage, current)
differ between the two battery types. That is, the charger would go through
exactly the same sequence of steps for either battery type, but would charge
to a slightly different voltage for each type and would use a slightly
different finish current for each type.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Hi Chris. I replied (well I thought I did) from work but no such
message in my outbox. So I will do it again
I agree and understand what you mean. Its just that I am unsure of all
the factors but for now, I will just do some rough calcs.
Lets go to the extreme:
Weight including freight etc 1500lbs
Speed 6mph
16 inch wheels I reckon
Acceleration isn't that important
And pretty flat ground I guess. Certainly no hills but a few bumps etc.
I did a bit more of a search and found a calc that was something like
HP := (weight in pounds) * speed / constant 550 * something
I have it outside in the car. I calculated out using 1000 lbs to be near
16 hp
Does that give us something to kick around?
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Chris Robison
Sent: Friday, December 16, 2005 8:35 AM
To: [email protected]
Subject: [BAYESIAN SPAM] - Re: Required horsepower - Bayesian Filter
detected spam
Your question is missing some important parameters. We need to know not
only how much weight you want to pull, but how fast you want to pull it
and with what kind of resistance. Are you pulling it on a trailer with
decent wheels over well-maintained roads or trails, or are you pulling
it on skids across uneven ground? How much do you care about
acceleration?
What about hills?
Power (the subject of your question) can be seen to comprise two
components -- a force (pounds, Volts, PSI, etc), and a speed or rate at
which that force is applied (ft/sec, Amps, CFM, etc). For example, for
about $40 I bought a winch at Harbor Freight that runs on a small, wimpy
12V motor. It can generate an enormous amount of force -- we used it to
slide a palette weighing several hundred pounds up a pair of wooden
ramps into the back of a pickup truck. But, it took forever, moving at
maybe a quarter inch per second under load. What small amount of
mechanical power the motor could generate was geared to heavily augment
torque at the expense of speed.
So, to pull 500kgs, you can do it with a 1/15th horsepower motor, but
you'll be moving it very slowly.
Maybe it would help to describe the load, and where you'll be carrying
it?
--chris
On Thu, December 15, 2005 1:37 pm, Peter May said:
> Hi all.
>
> I have been searching google and the net in general to answer my
> question and came across this list. Hopefully, someone can help me.
>
> I was intending to build an EV for my small farm. Purpose built and
> for certain tasks I have in mind. What I am trying to find out is what
> or how much horsepower is needed at the wheels? What I mean is if I
> use say a 2 hp motor and it goes through a 10:1 gear box or whatever,
> how do I know what it will be capable of. Or in another way, I way
> 130kgs, I want to tow say 100kgs, the car itself ways whatever kgs,
> how do I calculate the required horsepower (at the wheels) required to
move it etc?
>
> Hope you all find it an interesting question and can provide a few
> ideas.
>
> Alternatively, I would love to hear from people on or off list (which
> ever is more appropiate) with the horspower they have at the drive
> wheels and what weight etc they can move?
>
> Many thanks, Peter
>
>
Radio's, electronics, gadgets and gizmo's for sale @
http://www.gizmoman.net/gfs.htm
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36VOLT DC ELECTRICAL MOTOR AND PULLEY, NO RESERVE
Item number: 7572631728
Response from tech265
Item: 36VOLT DC ELECTRICAL MOTOR AND PULLEY, NO RESERVE (<A
HREF="http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7572631728&sspagename=ADME:L:RTQ:US:1";>7572631728</A>)
This message was sent while the listing was active.
tech265 is the seller.
Steve, The motor's length is 15.5''. With the pullies it measures 17-3/4''.
The motor diameter is 8''. Thanks Chuck
Looks like it could be a good drive motor for a small EV. I believe it is a
pump motor - only two terminal - one direction of rotation. Might be easy to
pull off that pully and mount a flywheel, or mount the flywheel directly to
the face oc the pulley. I already bought a different motor a few months back,
so I'll pass on this one, even though it is an 8" and mine is a 7.2". Already
have too much time and effort into reconditioning the one that I already have.
Otherwise, I would have bought this one. He also is selling the GE EV-1B
controller, but it only has a 48 V card, so you would have to change the card,
and that will cost you more than the controller. Just FYI, if you happen to
need parts.
Steve
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What is the maximum RPM limit of the WarP 9" ???? Is the limit because the
brushes will pull away from the commutator or the bearings won't take it?
Jody
-----Original Message-----
From: Mark Fowler [mailto:[EMAIL PROTECTED]
Sent: Thursday, December 15, 2005 1:40 PM
To: [email protected]
Subject: RE: CVT transmission for EV - long
Hi all,
Speaking (typing?) very generally...
An ICE is only really useful in the 2000 to 4000 rpm range.
Below that it has too little power, and above that it is too noisy and
life is reduced.
(yeah, I know, I'm speaking very generally)
Anyway, that's why ICE cars have multi-gear gearboxes - to make that
limited rev range available at any speed from starting to highway
speeds.
(we'll skip the going backwards bit for this discussion)
So, a CVT gives you an "infinitely" variable range from starting gear to
highway gear, meaning that the ICE can sit on it's even narrower "sweet
spot" rpm to give it the best efficiency and economy.
An equivalent sized electric motor has useful power from 0 to 6000 rpm.
(remember, I'm generalising)
With the right sized parts, you can run from starting right up to
highway speeds in the one gear.
With less than optimal parts, you might need a low gear and a high gear,
but that's about it.
What you do need in an EV is efficiency since our "fuel tanks" are
relatively much smaller than the ICE equivalent with respect to range.
CVTs have more losses than a manual gearbox (and much less than direct
connect), so the advantage of running the motor at its most efficient
rpm is lost.
Mark
> -----Original Message-----
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] On Behalf Of Seth Rothenberg
> Sent: Friday, 16 December 2005 4:19 AM
> To: [email protected]
> Subject: Re: CVT transmission for EV - long
>
>
> > Has ANYONE used the CVT transmission out of the Mini or any
> other for that
> > matter? This looks ideal for my smart car and would make
> the little woman
> > more likely to use the car. So if anyone knows anything
> good or bad about
> > this trans please reply on list.
>
> Related to this, I would like to hear if anyone knows what
> happened to a transmission I saw presented in
> Popular {Mechanics|Science} twenty-odd years ago.
> I recall that there were two cones back-to-back,
> and they were held so the axis was tilted but
> the opposing sides of the cones were horizontal.
>
> The funny thing is, I can't recall precisecly
> how they transferred power - I can think of
> two ways to do it...
> a) by bolting them together and varying where
> on the side of the cone the input is delivered
> (and output is one conelength away, on the sister cone)
> OR
> b) they are not connected, just on a common axis.
> The input would turn one cone, a cylindrical
> widget would surround both, contacting opposing
> edges of the two cones, thus transmitting and "gearing",
> and the second cone would drive the output.
>
> The second method, with the cylinder rings a bell, but
> the not-connected axle does not. I think it actually
> was two rings connected by a framework, not a whole cylinder.
>
>
> Also, another CVT idea....
> The wikipedia for CVT has a link to Anderson CVT.
> They use a belt to do the gearing/transfer mentioned,
> from the narrow of one cone to the wide of the other.
>
> There's a big thing about durability of belts.
>
>
> I had this idea, do you think it is nuts?
> What if you had the two cones, facing each other,
> side-by-side...one is input, the other output, and
> the transmission is just a rubber wheel that is
> jammed between them...position right-or-left to
> change ratio. i.e. the space between the
> Input surface and the output surface is constant
> from the (narrow input/wide output) to the
> (wide input/narrow output) side.
>
> The problem is wear....
>
> but it seems to me that this is such a simple
> design, it may be possible to simply stipulate
> that the ball has to be changed every X miles.
> The only issue is if that X will be in hundreds or
> thousands or....
>
> Is that nuts - or is it nuts and bolts and axles, etc.?
>
> Also, there are a couple ways to deal with this wear issue
> to extend the time of required maintenance.
> Anyone want to help?
> (of course, I might need to figure out if any patents
> will apply...)
>
> Thanks
> Seth
>
>
>
>
>
>
>
>
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I am not commenting on the stability of a threewheeler. I am just
forwarding a pic because it is cool.
http://www2u.biglobe.ne.jp/~WELBY/out.jpg
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On Dec 15, 2005, at 10:52 PM, Victor Tikhonov wrote:
I was talking about fundamental advantage for such an application
as *single speed* freeway capable vehicle, which was discussed,
where hi speed advantage of AC setup becomes too important to tip
the scale.
This is NOT a fundamental advantage of AC! I don't know how many people
have to tell you that before you will understand.
The DC answer is simple. A large enough motor (or water cooled but I
don't see any of them laying around), a 'Zilla 2k (we can even turn it
down to 280 battery amps to match the stuff you sell), and a pack
voltage similar to the one that gives the AC drives you sell a wide
power band.
Paul "neon" G.
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You can't take the etek to 72V 450A for road EV use, you are going to fry
it.
Same bad result with 200A though you double use time before self-destruction
(few seconds in all)
You can use it to 60V (but it will eat his brushes fast) at 200A for few
seconds and it is reliable (as EV commuter motor) at 48V and 200A not more.
Cooling it (brush side) with a big squirel type fan will improve reliability
a lot.
If you need 72V AND 200A use the PMG132 by perm motors company or Lynch 72V
version.
cordialement,
Philippe
Et si le pot d'échappement sortait au centre du volant ?
quel carburant choisiriez-vous ?
http://vehiculeselectriques.free.fr
Forum de discussion sur les véhicules électriques
http://vehiculeselectriques.free.fr/Forum/index.php
----- Original Message -----
From: "keith vansickle" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, December 15, 2005 5:42 PM
Subject: general questions re max for E-Tec
>
> to those familar with the E-Tec motor
>
> I am building a motor cycle with an e-tec and would
> like to know how far I can reasonably push it. The
> bike and rider will have a weight of 650 lbs. I am
> planing a 72v system with an alltrax 7245 controller,
> giving me the possibility of going 450 amps at 72 v
> for accelleration and crusing at somewhat less than
> 200 amps.
> Has anyone tried these with the e-tec?
> Do you think it will hold together?
> Can it be reinforced in some fashion to take these
> extra stresses?
> any info would be appreciated
>
> thanks
> keith
>
>
> __________________________________________________
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The problem with the rubber wheel is more than just wear, a lot of
effiency is lost in the squishing of the rubber.
the CVT I saw from nissan for high powered sports cars was two polished
half spheres a dogbone shaped roller was between them and the angle of
the roller was adjusted making it ride at different locations on the
input sphere from the output sphere. There is a lot of pressure holding
it togather against bearings and it is all metal to metal contact using
a special oil that increases grip between the surfaces.
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>From what I read, they wear mechanically but they don't carry as much
current, most the time so they are made of a differnt material (more
silver I think) From talking to the motor shop and reading online the
wear is less. I don't have one,.... yet
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Victor:
> Naturally, question then becomes why don't we have lobby
> as ARRL or especially EAA does. What's the fundamental difference
> between EV and Aircraft?
>
> Perhaps, partly because amateur built cars share the road with
> others and subject them to "unregulated" (so dangerous
> in the eyes of authorities) vehicles, possibly public complaints,
> etc. With an aircraft your failure is your only own problem
> (unless you crash into a residential area, but the available
> space for flying is regulated as well).
Well - I am afraid that is not that easy. Amateur build aircraft are not
'unsafer' than other planes. One will be supervised by EAA inspectors
during the building process. And, of course, one will have to comply with
all laws and regulations.
Why don't we have such a lobby? Because it is so much simpler and cheaper
to build you own car. One couldn't just take, say a Cessna, replace its
engine with a steam turbine and keep on flying. So - the EVing thing has
become a backyard shop tinkering thing - without the need of
organizational support.
But I am afraid the day will come that i.e. due to copyright* or Fed/State
restrictions, we might not be able to do that with our cars. This is why I
am suggesting a stronger, innovative organisation to prevent those things
from happening, to educate the general public and to lobby on behalf of
those of us, who would like to (and would be able to) build their car from
scratch.
Michaela
*Printer manufacturers just won a legal battle and now probibit their
customers to use any other brand's printer cartridge. They based this on a
copyright issue. That means, you open the box, you implicitly accept their
copyright including the limitation in regard to cartridges other
manufacturers. In theory (and I am sure it will happen) when you buy a
car, you will implictly declare your compliance to i.e. GM's copyright
that prohibits you from using anything else that OEM parts to repair your
car.
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I had seriously considered a "hybrid drive" AC/DC motor combo a while
back. The dual motors were combined with dual batteries packs - one
LiIon and one AGM. So the AC motor and LiIon's did the basic cruising
propulsion (and regen); the DC motor powered by the small AGM pack
kicked in for more power when the accelerator is pushed down further.
As a ground up production type vehicle it would be a ridiculously
complicated way to do things. For a home conversion, using parts
available, it was a way to get fun and range in a pick-up truck sized
vehicle. One of the smaller Siemens AC motors come with a female
"shaft". By getting NetGain to make an 8" DC motor with a custom tail
shaft to match, it would slide right into the AC motor for a slick
Siamese setup. As a conversion, the tranny would remain so neither motor
would be revved up to high RPMs.
The LiIons I was eyeing at the time weren't quite ready for prime time,
although Valance has modules out now that (cost aside) would fit the
bill perfectly. I then got into my 'new' OEM S-10 which has plenty of
power (100 KW) for practical purposes (compared to maybe 40 kW in my
previous S-10 conversion). Now I just need to keep the NiMH batteries happy.
But someday I'll make the perfect truck that can provide range AND 200
KW bursts for fun.... someday....
Mark Farver wrote:
Someone suggested this as DC/AC system once before. Use series DC for
its great starting torque, then switch to AC for its higher efficiency/
top RPM. You would need some way to decouple the DC motor from the
driveline to avoid overreving it. The added complexity of two different
drive system is probably not worth the gains, but it might be fun to
build for an exotic project.
--
Jim Coate
1970's Elec-Trak's
1998 Chevy S-10 NiMH BEV
1997 Chevy S-10 NGV Bi-Fuel
http://www.eeevee.com
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an electric motor will do the job you are looking for much better than a gas
as the slower a series motor goes the more torque it puts out . I replaced
my 20 hp gas lawn mower motor with an electric and find that it uses about
7,000 watts to give the same performance ( with 760 watts = 1 hp that's
about 8 hp with losses) . I've heard it said that 2.5 gas hp = 1 electric.
Remember electric motors like to spin fast , a 10:1 sounds low for a driving
around the farm. Why not a transmission off a lawn mower , having a few
gears , so you can put her in low and pull out a few trees :-) . I often
use my mower for moving things around and now that its not gas , as electric
it is much nicer to work with , being able to turn it of and on at any
moment, . Do you have a motor in mind?
steve clunn
----- Original Message -----
From: "Peter May" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, December 15, 2005 2:37 PM
Subject: Required horsepower
Hi all.
I have been searching google and the net in general to answer my
question and came across this list. Hopefully, someone can help me.
I was intending to build an EV for my small farm. Purpose built and for
certain tasks I have in mind. What I am trying to find out is what or
how much horsepower is needed at the wheels? What I mean is if I use say
a 2 hp motor and it goes through a 10:1 gear box or whatever, how do I
know what it will be capable of. Or in another way, I way 130kgs, I want
to tow say 100kgs, the car itself ways whatever kgs, how do I calculate
the required horsepower (at the wheels) required to move it etc?
Hope you all find it an interesting question and can provide a few
ideas.
Alternatively, I would love to hear from people on or off list (which
ever is more appropiate) with the horspower they have at the drive
wheels and what weight etc they can move?
Many thanks, Peter
--- End Message ---
