EV Digest 7016
Topics covered in this issue include:
1) Re: Catch Phrases
by ROBERT RICE <[EMAIL PROTECTED]>
2) shunt rating (mV)
by "Brian Pikkula" <[EMAIL PROTECTED]>
3) Re: Speed Reducers in the Nose
by "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
4) Re: Catch phrases for the EVDL
by ROBERT RICE <[EMAIL PROTECTED]>
5) Re: Speed Reducers in the Nose
by "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
6) Re: using a 12v volt meter to monitor traction voltage
by Danny Miller <[EMAIL PROTECTED]>
7) Re: shunt rating (mV)
by Jeff Major <[EMAIL PROTECTED]>
8) Re: shunt rating (mV)
by Christopher Robison <[EMAIL PROTECTED]>
9) Re: Energy unit conversion and comparison
by "Richard Krog" <[EMAIL PROTECTED]>
10) Re: LED headlights
by Danny Miller <[EMAIL PROTECTED]>
11) Re: how to modify signal to my stock tachometer
by "Michaela Merz" <[EMAIL PROTECTED]>
12) powering 12v cooling fan from pack voltage
by Markus Lorch <[EMAIL PROTECTED]>
13) RE: LED headlights
by Tim Humphrey <[EMAIL PROTECTED]>
14) RE: how to modify signal to my stock tachometer
by "Roger Stockton" <[EMAIL PROTECTED]>
15) RE: Speed Reducers in the Nose
by "Roger Stockton" <[EMAIL PROTECTED]>
16) RE: shunt rating (mV)
by "Roger Stockton" <[EMAIL PROTECTED]>
17) RE: powering 12v cooling fan from pack voltage
by Tim Humphrey <[EMAIL PROTECTED]>
18) Re: High Speed Electric Winch
by trev scribby <[EMAIL PROTECTED]>
19) Re: powering 12v cooling fan from pack voltage
by "Andre' Blanchard" <[EMAIL PROTECTED]>
20) Re: powering 12v cooling fan from pack voltage
by "Andre' Blanchard" <[EMAIL PROTECTED]>
21) RE: Speed Reducers in the Nose
by "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
22) Re: LED headlights
by Danny Miller <[EMAIL PROTECTED]>
23) RE: Speed Reducers in the Nose
by "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
24) Re: LED headlights
by "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
25) Re: LED headlights
by Danny Miller <[EMAIL PROTECTED]>
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Hi again, you guessed it, I'm figuring out my instrumentation..........
Say for a 500 ADC shunt, it is described as a 50mV shunt. Is that
50mV full scale (ie 500 A = 50mV) or some other ratio?
Again, I want to use newer looking gauges and want the ammeter to look
like my other gauges. So I'm going to have to custom modify this one.
Thanks again
--
Brian in TX
http://www.austinev.org/evalbum/960
http://www.evdub.blogspot.com/
It may seem like I am doing nothing, but on a cellular level I'm
really quite busy.
--- End Message ---
--- Begin Message ---
Zeke wrote:
>Couldn't you just put a CV shaft on the end of the motor
Zeke, on a Tropica, each wheel's motor is a foot or more forward of the
rear axle, with a belt connecting each motor to its wheel sprocket.
There's not a lot of unsprung chassis room back near the wheel to attach
things, especially two motors.
Bill Dennis
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Lee Hart wrote:
>This just means placing a 5:1 gear reduction between the motor shaft and
>the wheels. The "nose" of the motor is the shaft end.
On the Tropica, the motor is unsprung weight. It resides, however, close
to the pivot point of the rear suspension, so it doesn't move up and down
all that much. With Bob's suggestion, it seems like the motor would move
closer to the to the rear wheel (i.e., more towards the back of the
vehicle). Would this cause more handling problems because the unsprung
motor would be moving up and down further with each bump?
Thanks.
Bill Dennis
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--- Begin Message ---
There's no way to be sure how that meter works inside. If it was just a
normal 1mA meter movement then it'd work, but auto gauges typically do
something different because std needle movements bounce all over the
place. This may or may not have a fixed current draw. If current
decreases under some conditions then the voltage goes higher with a
divider like that. Or if it draws more current the voltage drops and it
may get "stuck".
Heating may be an issue. Not knowing what's inside there, if it drew
10mA- maybe a high estimate, but we just don't know- that's 1.44W on a
144V pack. OK no prob finding a 3W or 5W resistor there but it might be
a significant amount of heat depending on where it's mounted. If you
made 1.44W inside the plastic housing of this thing then that's significant.
Danny
Brian Pikkula wrote:
Hi,
Instead of using older looking gauges, I will be using more modern
type gauges. see: http://tinyurl.com/2desan
for example for the vac gauge I'll be using.
Is there anything inherently wrong with using a 12v dc voltmeter gague
(designed for the acc battery in ICEs)? I would just use a simple
voltage divider where R is th input resistance to the meter and put a
9R resistor in series with the meter so it sees 1/10 of the pack
voltage. Heating souldn't be an issue in the 9R since the input
resistance to the meter should be pretty high anyway.
No problems, right?
TIA
--- End Message ---
--- Begin Message ---
Hi Brian,
Yea, every one I ever saw had the 50 mV at the 500 amp
point. So full scale on a 500 amp meter has to be 50
mV.
Jeff
--- Brian Pikkula <[EMAIL PROTECTED]> wrote:
> Hi again, you guessed it, I'm figuring out my
> instrumentation..........
>
> Say for a 500 ADC shunt, it is described as a 50mV
> shunt. Is that
> 50mV full scale (ie 500 A = 50mV) or some other
> ratio?
>
> Again, I want to use newer looking gauges and want
> the ammeter to look
> like my other gauges. So I'm going to have to
> custom modify this one.
>
> Thanks again
>
> --
> Brian in TX
> http://www.austinev.org/evalbum/960
> http://www.evdub.blogspot.com/
> It may seem like I am doing nothing, but on a
> cellular level I'm
> really quite busy.
>
>
____________________________________________________________________________________
Boardwalk for $500? In 2007? Ha! Play Monopoly Here and Now (it's updated for
today's economy) at Yahoo! Games.
http://get.games.yahoo.com/proddesc?gamekey=monopolyherenow
--- End Message ---
--- Begin Message ---
On Wed, 2007-07-11 at 13:49 -0500, Brian Pikkula wrote:
> Hi again, you guessed it, I'm figuring out my instrumentation..........
>
> Say for a 500 ADC shunt, it is described as a 50mV shunt. Is that
> 50mV full scale (ie 500 A = 50mV) or some other ratio?
Yep, that's the idea. A 500A/50mV shunt will show 50mV of voltage drop
at 500A. You can get them in other current ratings, and other millivolt
ranges as well. I have several small ones in my parts bin, including a
100A/100mV shunt (which would be equivalent to, but a little more robust
than, a 50/50 shunt). Then, there's the 3000A/50mV shunt, which weighs
about 3-4 pounds. :-)
As an aside (though I don't think you'll have a problem with a shunt of
this size), I've learned that a 500A shunt can't be used continuously at
500A. Shunts are generally only good for about 75% of their rated
current, continuously, without some kind of forced cooling.
There's a threshold temperature (not sure what it is) for the metal
that's used in the shunt's resistive element. If heated beyond this
temperature, the resistance of the shunt will change permanently, and
the shunt will have to be replaced.
--
Christopher Robison
[EMAIL PROTECTED]
http://ohmbre.org <-- 1999 Isuzu Hombre + Z2K + Warp13!
--- End Message ---
--- Begin Message ---
1 watt is the same as 1 joule.
Not quite. A Watt is a measure of power while a Joule is a measure of
work (energy). 1 Watt of power will consume 1 Joule of energy in 1
second. Work = Power * Time.
It also says the amount of energy contained
in 1 gallon of gasoline is 1.3X10 to the 8th power, joules
Automotive gasoline contains around 45 MJ/kg. A gallon of gas weighs
about 6.25 lbs giving around 281 MJ or 2.8 X 10^8 Joules -- about
double the amount you found, but that would depend on which Google
link I followed.
So if I drive 55 miles @ 55 mph, I've used 11.715 kilowatts?
Close, just add the hour component: 11.715 kWh or around 42 MJ.
Let's -assume- an early 2000's Ford or GM large SUV (Expedition, Suburban,
Tahoe, Escalade or whatever) gets 14 mpg at 55 mph. That's .07 gallons per
mile. .07*130,000,000 gallons contains 9,100,000 watts of energy sooooooooo
our mythical SUV gets 9,100 kwh/mile and it uses 500,500 kw to drive 55
miles.
Oops, you're off by the number of seconds in an hour: 0.07 gal/mile *
130,000,000 J/gal = 9,100,000 J/mile. To convert to Wh, divide by
3,600 seconds in an hour. This would give you 2527 Wh, or 2.527 kWh
per mile. Using the numbers I found above, I get about 5.6 kWh/mile.
You're right, these numbers are a lot higher than the 250 Wh/mile you
see in a typical EV. Then again, Peter has a good point in that "Well
to Wheels" is a better apples-to-apples comparison.
I'm about 20 years removed from my physics class, so corrections are welcome!
Richard Krog
--- End Message ---
--- Begin Message ---
Damn I forgot to look up optics at the time, I assumed they were too new
(optics generally must be made for a specific device) but nope there are
some there for the Rebel. They're cheap.
Well there's an 8.9 deg narrow round beam and a 40 deg x 9.5 deg
elliptical beam. An elliptical might be best because the area of the
road you need to view is wider than the distance that beam would be
allowed to spread in the vertical direction since it would blind
people. Actually with a round pattern, if it's narrow enough we could
still do something unique due to the multiple emitters. Point one
narrow beam straight ahead, one off a few degrees to the side, another a
few more degrees etc. The spread of a series of overlapping round beams
could form a decent elongated spread.
OK, neat. Yeah we can pretty much do such a thing today I think except
only the 0070 emitters are available now not the 0080. Need like 8 per
side, need an optic per lens, make a thermal PCB, I know a high
efficiency LED driver which could operate straight off a HV pack.
That's under $100 for the basic parts.
There would be a lot of mounting issues, they'd probably need an outer
cover that could be kept clean. There may still be overheating issues.
Beam spread will likely be an issue. This does not address high beam
although I don't see why it couldn't, maybe just another row pointed
higher to cover the high end? They would probably not be completely
street legal here. And let's not kid ourselves- even if it took zero
power, it would not increase your range substantially. An 8-emitter
lamp, one per side, is still 20W per lamp for 1160 lumens minus whatever
light isn't captured by the optics (that could lose 10%-20%).
Danny
Bukosky, Allen wrote:
A couple of people are making molded plastic lenses for these and
similar devices. You would need one lense per LED (there are some quad
lenses out there, too).
Google "lenses for LEDs".
Allen
-----Original Message-----
From: Danny Miller [mailto:[EMAIL PROTECTED]
Sent: Wednesday, July 11, 2007 1:29 AM
To: ev@listproc.sjsu.edu
Subject: LED headlights
Oooh, got some stock of the latest LED emitters on the market, Luxeon
Rebels.
Not only are they more efficient, they're higher power and most
importantly significantly more tolerant of high temps. The 50K hr life
rating is with a 135C junction temperature. The thermal pad on back is
electrically neutral and solderable. A sizable copper PCB area (half a
sq in or so) can dissipate the heat and stay within specification, I
took measurements. And I wasn't pulling any special tricks here.
145 lumens at 2.52W is the book rating, although my part here has a
significantly lower forward voltage at the specified current and is only
drawing about 2W.
A low beam halogen is 1000 lumens or so. These devices are fairly
cheap, under $4 in singles.
The prob is these things spread light over 160 deg. That's a prob
because even a perfectly designed lens can only focus the light it
captures and even a foot-wide lens can't capture over 160 deg. Either
some will just be lost- without advanced computer-designed optics it
can't be redirected into a beam, it must be absorbed by an opaque
surface to prevent creating an unacceptable side beam. The reflector
design used in normal headlights would be problematic because the
heatsink is opaque and generally large which will block much of the
reflected beam unless we pull some tricks like a bigger reflector or a
smaller heatsink (water cooling would do nicely).
Well don't jump into it right away. Unless you're a genius this would
probably not work. And really the power savings aren't all that great.
Anyways, the devices went out of stock, I bought the last 3 high power
whites on the market right now (sorry fellows). They've got the lower
power bin ones available, like 10% less output for the same power input.
Danny
--- End Message ---
--- Begin Message ---
Brian: I had the same problem with my S-10. The ECM got lost by the
previous owner and I haven't had a good signal from the sensor I could
feed to the speedo.
Simple solution: A signal converter from Dakota Digital. I put it between
sensor and tach, configured and calibrated it and that was it. Works
flawless.
mm.
> Hello again,
>
> I have a newer car that uses a ECM for most of the ICE stuff and I'd
> like to get rid of the ECM (going for ~$400 on EBay). I want to use
> my stock tach (for looks and especially since its redline is very
> close to the stock tach in there now [ice was a diesel tdi]). The
> signal from the ECM to the cluster computer is a square wave 0-5 V
> (TTL I'm guessing) 1 pulse/rev. Since I've not dealt with tachs in
> the past and there isn't much info on the web, i'm not sure what to
> do. I
>
> s there anything that off the shelf that can make such a signal OR
> what combination of pickup + an analog circuit that could do the same?
>
> Thanks.
>
> --
> Brian in TX
> http://www.austinev.org/evalbum/960
> http://www.evdub.blogspot.com/
> It may seem like I am doing nothing, but on a cellular level I'm
> really quite busy.
>
--- End Message ---
--- Begin Message ---
hi there,
got a thought here on how to improve my EV and was wondering what other
list members were thinking about it.
I have a 12V cooling fan to cool my motor. Originally it was turned on
by a temperature switch in the motor but, based on recommendation from
the list, I turn it on permanently on virtually every drive way before
the motor heats up with my ignition switch. Problem is that the constant
load of the cooling fan on the 12V system basically loads my small dc-dc
to its capacity (I have two 4A 13.8V DCDCs, the cooling fan needs 4A
when running on low).
As the fan is just a regular DC motor I was wondering if it would not be
smarter to power it via a small motor controller i.e. like those used in
scooters. But I have a hard time finding a (dirt cheap) dc motor
controller with a input voltage of 80-130V and roughly 4A output. Can I
go with a very simple circuit and build one myself as it does not have
to be very accurate in terms of output voltage etc. Just roughly the
right duty cycle/motor amperage.
Any thoughts?
Thanks
Markus
--- End Message ---
--- Begin Message ---
Think outside the bun......
We no longer need one light per side... how about a thin line of light all the
way across the front...like a glowing bumper. Every other LED is off for low on
for high.
--
Stay Charged!
Hump
I-5, Blossvale NY
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
> Behalf Of Danny Miller
> Sent: Wednesday, July 11, 2007 2:20 PM
> To: ev@listproc.sjsu.edu
> Subject: Re: LED headlights
>
> Damn I forgot to look up optics at the time, I assumed they were too new
>
> (optics generally must be made for a specific device) but nope there are
>
> some there for the Rebel. They're cheap.
>
> Well there's an 8.9 deg narrow round beam and a 40 deg x 9.5 deg
> elliptical beam. An elliptical might be best because the area of the
> road you need to view is wider than the distance that beam would be
> allowed to spread in the vertical direction since it would blind
> people. Actually with a round pattern, if it's narrow enough we could
> still do something unique due to the multiple emitters. Point one
> narrow beam straight ahead, one off a few degrees to the side, another a
>
> few more degrees etc. The spread of a series of overlapping round beams
>
> could form a decent elongated spread.
>
> OK, neat. Yeah we can pretty much do such a thing today I think except
> only the 0070 emitters are available now not the 0080. Need like 8 per
> side, need an optic per lens, make a thermal PCB, I know a high
> efficiency LED driver which could operate straight off a HV pack.
> That's under $100 for the basic parts.
>
> There would be a lot of mounting issues, they'd probably need an outer
> cover that could be kept clean. There may still be overheating issues.
>
> Beam spread will likely be an issue. This does not address high beam
> although I don't see why it couldn't, maybe just another row pointed
> higher to cover the high end? They would probably not be completely
> street legal here. And let's not kid ourselves- even if it took zero
> power, it would not increase your range substantially. An 8-emitter
> lamp, one per side, is still 20W per lamp for 1160 lumens minus whatever
>
> light isn't captured by the optics (that could lose 10%-20%).
>
> Danny
>
> Bukosky, Allen wrote:
>
>>A couple of people are making molded plastic lenses for these and
>>similar devices. You would need one lense per LED (there are some quad
>>lenses out there, too).
>>
>>Google "lenses for LEDs".
>>
>>Allen
>>
>>
>>-----Original Message-----
>>From: Danny Miller [mailto:[EMAIL PROTECTED]
>>Sent: Wednesday, July 11, 2007 1:29 AM
>>To: ev@listproc.sjsu.edu
>>Subject: LED headlights
>>
>>Oooh, got some stock of the latest LED emitters on the market, Luxeon
>>Rebels.
>>
>>Not only are they more efficient, they're higher power and most
>>importantly significantly more tolerant of high temps. The 50K hr life
>
>>rating is with a 135C junction temperature. The thermal pad on back is
>
>>electrically neutral and solderable. A sizable copper PCB area (half a
>
>>sq in or so) can dissipate the heat and stay within specification, I
>>took measurements. And I wasn't pulling any special tricks here.
>>
>>145 lumens at 2.52W is the book rating, although my part here has a
>>significantly lower forward voltage at the specified current and is
> only
>>
>>drawing about 2W.
>>
>>A low beam halogen is 1000 lumens or so. These devices are fairly
>>cheap, under $4 in singles.
>>
>>The prob is these things spread light over 160 deg. That's a prob
>>because even a perfectly designed lens can only focus the light it
>>captures and even a foot-wide lens can't capture over 160 deg. Either
>>some will just be lost- without advanced computer-designed optics it
>>can't be redirected into a beam, it must be absorbed by an opaque
>>surface to prevent creating an unacceptable side beam. The reflector
>>design used in normal headlights would be problematic because the
>>heatsink is opaque and generally large which will block much of the
>>reflected beam unless we pull some tricks like a bigger reflector or a
>>smaller heatsink (water cooling would do nicely).
>>
>>Well don't jump into it right away. Unless you're a genius this would
>>probably not work. And really the power savings aren't all that great.
>>
>>Anyways, the devices went out of stock, I bought the last 3 high power
>>whites on the market right now (sorry fellows). They've got the lower
>>power bin ones available, like 10% less output for the same power
> input.
>>
>>Danny
>>
>>
>>
>>
--- End Message ---
--- Begin Message ---
Brian Pikkula wrote:
> I have a newer car that uses a ECM for most of the ICE stuff and I'd
> like to get rid of the ECM (going for ~$400 on EBay). I want to use
> my stock tach (for looks and especially since its redline is very
> close to the stock tach in there now [ice was a diesel tdi]). The
> signal from the ECM to the cluster computer is a square wave 0-5 V
> (TTL I'm guessing) 1 pulse/rev. Since I've not dealt with tachs in
> the past and there isn't much info on the web, i'm not sure what to
> do. Is there anything that off the shelf that can make such a signal
> OR
> what combination of pickup + an analog circuit that could do the same?
EV Parts sells a nice nylon collar that fits right on the tailshaft of
an ADC motor and has a pair of magnets embedded in it to drive a tach
pickup. This gives 2 pulses per rev, which is the standard for most 4
cylinder engines and tachs.
Digikey has (or had?) a 3-pin hall effect sensor (from Panasonic, IIRC)
that can directly provide a TTL level output. Have a look at their
catalog/site.
If you need only one pulse/rev, you might remove one magnet from the EV
Parts collar, or stick a CMOS or TTL flip-flop between the sensor and
the tach to provide a divide-by-2 function.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
[EMAIL PROTECTED] wrote:
> I have two Tropica chassis. One is in the original
> configuration, as I described in my previous post, with
> the motor as unsprung weight. The second chassis, however,
> has been modified so that the motor has become sprung
> weight. A stiffener was added to the floor pan behind
> each seat, and the motor is attached there in such a way
> that the shaft of the motor lines up exactly with the pivot
> point of the rear suspension.
> Therefore, as the suspension moves up and down, the motor
> and wheel sprockets always remain the same distance from
> each other.
>
> It seemed pretty clever to me; does anyone have pros/cons
> that they can see about this configuration?
The con is that it requires modifying the chassis and only works if the
motor shaft is exactly aligned with the suspension pivot. Changing the
distance between the motor and wheel pulleys means having to buy
(expensive) new longer toothed belts.
Something to bear in mind is that the original configuration had the
motor located on the trailing arm which means the distance between the
driving and driven pulleys was already constant as the suspension moved
up and down.
The only thing that moving the motor(s) to the chassis does is make all
of their weight sprung, which *might* have a small effect on handling.
I doubt the effect would be perceptible on a Tropica running a stock
pack of floodies since the sprung to unsprung weight ratio is not going
to have changed much at all. If you were running a lightweight pack of
AGMs or Li-Ion, the sprung weight might be reduced enough that this
small reduction in unsprung weight would yield a perceptible benefit.
I say "small" because only part of the motor weight is unsprung in the
original configuration since the motors are located nearer to the
suspension pivots than are the wheels. Let's say the distance from the
motor to the wheel is 2x the distance from the motor to the pivot; this
means that when the wheel travels vertically 3", the motor only travels
1" and so only 1/3 of the motor weight is considered unsprung (just as
only part of the trailing arm weight is considered unsprung). The
ADC6.7's are relatively light to start with, so moving them to the
chassis only reduces the unsprung weight a small amount.
This mod might have greater benefit if one were also upgrading the 6.7's
to heavier 8's, though I think the point of Bob S's hotrodding
suggestion is that the toothed belts shouldn't be used at these higher
power levels. I'm pretty sure Bob's intention was that the pair of 8's
would be mounted to the vehicle chassis above and inboard of the wheels
so that a CV jointed axle could directly connect the output of each 5:1
gear reduction to its wheel.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Christopher Robison wrote:
> There's a threshold temperature (not sure what it is) for the metal
> that's used in the shunt's resistive element. If heated beyond this
> temperature, the resistance of the shunt will change permanently, and
> the shunt will have to be replaced.
It isn't actually that bad. Yes, the shunt will change resistance
permanently if overheated, but it certainly wouldn't need replacing
outside of a lab environment. The average shunt is a precision
instrument, accurate from the factory for perhaps 0.1%; when overheated
it might shift and no longer meet this tolerance, but that's of no
concern for us in our EV because our instruments aren't nearly that
accurate anyway.
On the other hand, if you really feel compelled to replace your
overheated shunts, I'll take them off your hands anytime and even give
you a couple bucks apiece for 'em! ;^>
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
How about finding a 120VAC blower with a universal motor, and just drive it
from pack voltage. Might be cheaper. Most 120VAC blowers I've seen were
universal motors. I have a couple if you want one.... but you're in Germany
now, right? Might be cheaper to find one already over there.
--
Stay Charged!
Hump
I-5, Blossvale NY
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
> Behalf Of Markus Lorch
> Sent: Wednesday, July 11, 2007 3:25 PM
> To: Electric Vehicle Discussion List
> Subject: powering 12v cooling fan from pack voltage
>
>
> hi there,
>
> got a thought here on how to improve my EV and was wondering what other
> list members were thinking about it.
>
> I have a 12V cooling fan to cool my motor. Originally it was turned on
> by a temperature switch in the motor but, based on recommendation from
> the list, I turn it on permanently on virtually every drive way before
> the motor heats up with my ignition switch. Problem is that the constant
>
> load of the cooling fan on the 12V system basically loads my small dc-dc
>
> to its capacity (I have two 4A 13.8V DCDCs, the cooling fan needs 4A
> when running on low).
>
> As the fan is just a regular DC motor I was wondering if it would not be
>
> smarter to power it via a small motor controller i.e. like those used in
>
> scooters. But I have a hard time finding a (dirt cheap) dc motor
> controller with a input voltage of 80-130V and roughly 4A output. Can I
> go with a very simple circuit and build one myself as it does not have
> to be very accurate in terms of output voltage etc. Just roughly the
> right duty cycle/motor amperage.
>
> Any thoughts?
>
> Thanks
> Markus
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Paul,
WOW, work life cought up with me, had to shelve this
project for a couple of weeks.Back on track now. I
started a new yahoo account almost a month ago, its
almost maxed out. I love the EV list!!
Thanks so much for helping out. I really like hearing
a golf cart motor may work. I know that golf cart
motors need some fabricating, but still in my bargain
ballpark.
Thanks so much!!
trevor
--- Paul <[EMAIL PROTECTED]> wrote:
> On Jun 19, 2007, at 12:55 PM, trev scribby wrote:
>
> > Below is the power curve for a Honda 9HP motor, i
> have
> > the "overseas-ebay equivalent". Not sure exactly
> how
> > to read the chart, but hopefully you guys can
> help.
> >
> > http://www.trupower.com/honda/270/gxperg270.gif
>
> It looks like you need around 14 ft/lb of torque
> over a rpm range
> that an electric motor would be happy with.
>
> How long does the engine/motor operate each pull?
> This looks like
> something that a golf cart motor and controller
> could handle. Beat up
> old ones with dead batteries are often cheap.
>
> Paul "neon" G.
>
>
____________________________________________________________________________________
Be a better Globetrotter. Get better travel answers from someone who knows.
Yahoo! Answers - Check it out.
http://answers.yahoo.com/dir/?link=list&sid=396545469
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--- Begin Message ---
This could likely be hacked into something you could use. Higher volt
MOSFET also D1 and C7, lose D2, add a separate power supply for the main
circuit, and add some kind of isolation in the drive to the MOSFET.
http://www.electronickits.com/kit/complete/motor/ck1400.htm
At 02:24 PM 7/11/2007, you wrote:
hi there,
got a thought here on how to improve my EV and was wondering what other
list members were thinking about it.
I have a 12V cooling fan to cool my motor. Originally it was turned on by
a temperature switch in the motor but, based on recommendation from the
list, I turn it on permanently on virtually every drive way before the
motor heats up with my ignition switch. Problem is that the constant load
of the cooling fan on the 12V system basically loads my small dc-dc to its
capacity (I have two 4A 13.8V DCDCs, the cooling fan needs 4A when running
on low).
As the fan is just a regular DC motor I was wondering if it would not be
smarter to power it via a small motor controller i.e. like those used in
scooters. But I have a hard time finding a (dirt cheap) dc motor
controller with a input voltage of 80-130V and roughly 4A output. Can I go
with a very simple circuit and build one myself as it does not have to be
very accurate in terms of output voltage etc. Just roughly the right duty
cycle/motor amperage.
Any thoughts?
Thanks
Markus
__________
Andre' B. Clear Lake, Wi.
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Or read the notes in the PDF on external power supplies. ;)
Seems they cover that with a jumper.
At 03:15 PM 7/11/2007, you wrote:
This could likely be hacked into something you could use. Higher volt
MOSFET also D1 and C7, lose D2, add a separate power supply for the main
circuit, and add some kind of isolation in the drive to the MOSFET.
http://www.electronickits.com/kit/complete/motor/ck1400.htm
__________
Andre' B. Clear Lake, Wi.
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--- Begin Message ---
Thanks, Roger. Yes, I was referring mostly to the handling/performance
gain in sprung vs. unsrpung weight. The plans are indeed to user
light-weight batteries in the car. And yes, again (boy, you nails all
these) I was hoping to upgrade the motors--I don't a full 8-incher would
fit, but maybe Hi-torque Husted could come up with something.
Also, thanks for clarifying what Bob Schneewiess meant. I had assumed he
meant keeping the motors as unsprung weight further back on the suspension.
But may you and Zeke are more accurate that he meant using a CV joint and
sprung-weight motors.
Bill
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Indeed. In a stock vehicle, the headlight cavities are still available.
Actually with the construction of the LEDs then they could certainly be
in a lot of flexible locations. And the thermal issues are less when
not bunched in one place.
Headlights do not work well when mounted low such as on the bumper. To
avoid blinding people the headlights must be angled downward to
terminate on the road a set distance away. If lower the angle to do
that is much flatter. This makes the beam spread out a lot more and
slight changes in the road angle or vehicle angle (putting stuff in the
trunk) causes a very large difference in where the beam spread lands.
Danny
Tim Humphrey wrote:
Think outside the bun......
We no longer need one light per side... how about a thin line of light all the
way across the front...like a glowing bumper. Every other LED is off for low on
for high.
--
Stay Charged!
Hump
I-5, Blossvale NY
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Danny Miller
Sent: Wednesday, July 11, 2007 2:20 PM
To: ev@listproc.sjsu.edu
Subject: Re: LED headlights
Damn I forgot to look up optics at the time, I assumed they were too new
(optics generally must be made for a specific device) but nope there are
some there for the Rebel. They're cheap.
Well there's an 8.9 deg narrow round beam and a 40 deg x 9.5 deg
elliptical beam. An elliptical might be best because the area of the
road you need to view is wider than the distance that beam would be
allowed to spread in the vertical direction since it would blind
people. Actually with a round pattern, if it's narrow enough we could
still do something unique due to the multiple emitters. Point one
narrow beam straight ahead, one off a few degrees to the side, another a
few more degrees etc. The spread of a series of overlapping round beams
could form a decent elongated spread.
OK, neat. Yeah we can pretty much do such a thing today I think except
only the 0070 emitters are available now not the 0080. Need like 8 per
side, need an optic per lens, make a thermal PCB, I know a high
efficiency LED driver which could operate straight off a HV pack.
That's under $100 for the basic parts.
There would be a lot of mounting issues, they'd probably need an outer
cover that could be kept clean. There may still be overheating issues.
Beam spread will likely be an issue. This does not address high beam
although I don't see why it couldn't, maybe just another row pointed
higher to cover the high end? They would probably not be completely
street legal here. And let's not kid ourselves- even if it took zero
power, it would not increase your range substantially. An 8-emitter
lamp, one per side, is still 20W per lamp for 1160 lumens minus whatever
light isn't captured by the optics (that could lose 10%-20%).
Danny
Bukosky, Allen wrote:
A couple of people are making molded plastic lenses for these and
similar devices. You would need one lense per LED (there are some quad
lenses out there, too).
Google "lenses for LEDs".
Allen
-----Original Message-----
From: Danny Miller [mailto:[EMAIL PROTECTED]
Sent: Wednesday, July 11, 2007 1:29 AM
To: ev@listproc.sjsu.edu
Subject: LED headlights
Oooh, got some stock of the latest LED emitters on the market, Luxeon
Rebels.
Not only are they more efficient, they're higher power and most
importantly significantly more tolerant of high temps. The 50K hr life
rating is with a 135C junction temperature. The thermal pad on back is
electrically neutral and solderable. A sizable copper PCB area (half a
sq in or so) can dissipate the heat and stay within specification, I
took measurements. And I wasn't pulling any special tricks here.
145 lumens at 2.52W is the book rating, although my part here has a
significantly lower forward voltage at the specified current and is
only
drawing about 2W.
A low beam halogen is 1000 lumens or so. These devices are fairly
cheap, under $4 in singles.
The prob is these things spread light over 160 deg. That's a prob
because even a perfectly designed lens can only focus the light it
captures and even a foot-wide lens can't capture over 160 deg. Either
some will just be lost- without advanced computer-designed optics it
can't be redirected into a beam, it must be absorbed by an opaque
surface to prevent creating an unacceptable side beam. The reflector
design used in normal headlights would be problematic because the
heatsink is opaque and generally large which will block much of the
reflected beam unless we pull some tricks like a bigger reflector or a
smaller heatsink (water cooling would do nicely).
Well don't jump into it right away. Unless you're a genius this would
probably not work. And really the power savings aren't all that great.
Anyways, the devices went out of stock, I bought the last 3 high power
whites on the market right now (sorry fellows). They've got the lower
power bin ones available, like 10% less output for the same power
input.
Danny
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Thanks, Roger. Yes, I was referring mostly to the handling/performance
gain in sprung vs. unsrpung weight. The plans are indeed to user
light-weight batteries in the car. And yes, again (boy, you nails all
these) I was hoping to upgrade the motors--I don't a full 8-incher would
fit, but maybe Hi-torque Husted could come up with something.
Also, thanks for clarifying what Bob Schneewiess meant. I had assumed he
meant keeping the motors as unsprung weight further back on the suspension.
But may you and Zeke are more accurate that he meant using a CV joint and
sprung-weight motors.
Bill
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On 11 Jul 2007 at 13:19, Danny Miller wrote:
> There would be a lot of mounting issues, they'd probably need an outer cover
> that could be kept clean. There may still be overheating issues. Beam
> spread will likely be an issue
Not to mention the little matter of DOT approval.
> They would probably not be completely street legal here.
I'd say not. However, you could almost certainly get away with them as fog
or driving lights, and maybe as high beams.
> even if it took zero power, it would not increase your
> range substantially.
My point exactly. The energy savings is trivial. You'd get appreciably more
range improvement out of spending your money on LRR (or LRR-er ;-) tires,
or finding a way to reduce brake drag.
I suppose you could argue that it's a way to capture more public attention, for
those who are "EVangelists" (with apologies to Bruce ;-).
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They do have a huge awesome factor, one that is really beyond
explanation. Overall the public- and myself- have a strong attraction
to LEDs that is pretty hard to explain. It is just awesome overall, and
has at least some practical merit on some levels.
DOT would concern me... it would be hard to gauge the likelihood of
being cited for having an illegal headlight. This might just be a
ticket for having a headlight out, it's hard to say. Being visibly
different from a long way away, yeah it seems plausible that the
question could actually come up. Cops could see something different
about you just driving down the road. One could hope that being white,
bright, and going basically where the light needs to go that they
wouldn't see an issue with it.
Vehicle inspection time might be another matter. I am unqualified to
even speculate. You could always swap them out...
Danny
David Roden (Akron OH USA) wrote:
My point exactly. The energy savings is trivial. You'd get appreciably more
range improvement out of spending your money on LRR (or LRR-er ;-) tires,
or finding a way to reduce brake drag.
I suppose you could argue that it's a way to capture more public attention, for
those who are "EVangelists" (with apologies to Bruce ;-).
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