EV Digest 4576
Topics covered in this issue include:
1) Re: Motor dynometer
by Rod Hower <[EMAIL PROTECTED]>
2) Re: Motor dynometer
by "M.G." <[EMAIL PROTECTED]>
3) Re: Silver Bullet Electric Z Car 1/4 Mile Run Results
by Rush <[EMAIL PROTECTED]>
4) Re: Silver Bullet Electric Z Car 1/4 Mile Run Results
by "Roderick Wilde" <[EMAIL PROTECTED]>
5) RE: Silver Bullet Electric Z Car 1/4 Mile Run Results
by "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
6) Re: Silver Bullet Electric Z Car 1/4 Mile Run Results
by Otmar <[EMAIL PROTECTED]>
7) Re: FW: New EV - Question
by [EMAIL PROTECTED]
8) Re: thermally conductive gel
by "David Chapman" <[EMAIL PROTECTED]>
9) Re: Motor dynometer
by "David Chapman" <[EMAIL PROTECTED]>
10) Re: Silver Bullet Electric Z Car 1/4 Mile Run Results
by "Roderick Wilde" <[EMAIL PROTECTED]>
11) Re: Motor dynometer
by Lee Hart <[EMAIL PROTECTED]>
12) Re: Silver Bullet Electric Z Car 1/4 Mile Run Results
by Lee Hart <[EMAIL PROTECTED]>
13) RE: New EV bikes?
by "Joe Vitek" <[EMAIL PROTECTED]>
14) Re: China's Cyclists Take Charge
by Martin Klingensmith <[EMAIL PROTECTED]>
15) Re: Silver Bullet Electric Z Car 1/4 Mile Run Results
by Danny Miller <[EMAIL PROTECTED]>
16) Re: What is going on? Problems while on the road ...
by "Paul G." <[EMAIL PROTECTED]>
17) 200VDC to 120VAC Inverter
by Edward Ang <[EMAIL PROTECTED]>
18) 144V Deka Dominator profile?
by Tom Hudson <[EMAIL PROTECTED]>
19) Re: 80v AC 3 phase EV Traction Motors and low voltage AC controllers
by Lee Hart <[EMAIL PROTECTED]>
--- Begin Message ---
Mike,
I setup a homebrew dyno in my lab at work,
http://www.qsl.net/w8rnh/dyno/dyno2.jpg
The motor on the left is a 72Vdc NEV GE motor (sepex)
and
the gold motor on the right is a BLDC that I was
testing with my control.
I don't have a link at home, remind me and I'll supply
one stored at work for the load resistors I used.
I connected several kW resistors I bought from a
surplus sight (about 0.017 ohms I think?) across the
A1 and A2 armature connections. I used a 3Amp supply
on F1 and F2 of the shunt winding. With 1-2 amps on
the shunt winding I was able to produce a 100A load at
24V on the NEV motor (that's 2.4kW). The resistors I
bought surplus where only $17 each and could handle
several kW (their about 2 foot long and 5" diameter
heavy duty metal coils). So, the dyno load energy was
pumped into these mega resistors as heat and I think
you could go up to several Hp with just a couple of
them.
Rod
--- Ryan Stotts <[EMAIL PROTECTED]> wrote:
> M.G. wrote:
>
> > If I connect the two motors together what should I
> use for
> > a suitable load on the series motor?
>
> What method will you use to measure the hp/tq?
>
>
--- End Message ---
--- Begin Message ---
I am not worried about the hp and torque. I know the motor will provide
enough. What I will be trying to accomplish is a high voltage controller
for the sem motor.
It is set up for 48 volts from the factory, I would like to modify it to
run at approx 150 volts.
Mike G.
M.G. wrote:
If I connect the two motors together what should I use for
a suitable load on the series motor?
What method will you use to measure the hp/tq?
--- End Message ---
--- Begin Message ---
From: "Ryan Stotts" <[EMAIL PROTECTED]>
> Is 170 volts the absolute limit at all rpms? How does Netgain get 192
> from theirs?
Is that true? For a 9" ADC motor the limit is 170 vdc that you can put into it?
What happens after that? I plan to do a 180 vdc pack...
Rush
--- End Message ---
--- Begin Message ---
In diagnosing any electric vehicle you need to start with metering. It will
be the most worthwhile money you spend. It will stop all this armchair EV
List quarterbacking. This vehicle is almost as complex as "Gone Postal". It
needs three motor amp meters, three motor volt meters, one battery volt
meter, one battery amp meter and a tachometer and a camera mounted to record
their readings through the quarter because things happen so fast you do not
have time to see them all at once. Only then will you know if the motors are
going to sleep or whether your batteries are sagging too much. It also
sounds to me by John's description "with the Silver Bullet lunging off the
line, tires squealing loudly" and the poor 60 foot times that there are
traction problems. That first sixty feet is very critical on your final ET.
As Dennis Berube says, you should only turn the tires one and a half turns
before they bite. That is why he has lines on the side of his tires and
video tapes his launches. Take it from a guy who has thousands of EV drags
under his belt. Dennis has a lot to teach all of us! From my seat of the
pants it does sound as if either the motors are going to sleep or the
batteries are sagging. Without the meters you will never know what it is. I
do not agree with advancing the motors on a low voltage system. Just my two
cents worth, but what the heck do I know about EV drag racing.:-)
Roderick Wilde
"Suck Amps EV Racing"
www.suckamps.com
----- Original Message -----
From: "John Wayland" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Saturday, August 13, 2005 9:14 AM
Subject: Silver Bullet Electric Z Car 1/4 Mile Run Results
Hello to All,
OK, it's Saturday morning, the day after.....Last night the deadly trio of
Tim, Jeffrey, and Plasma Boy returned to PIR with the Silver Bullet to see
what we could squeeze out of it in the 1/4 mile as a follow up to last
Wednesday night's 1/8 mile runs. We're having a lot of fun racing this
whistling beast, but we're also a bit disappointed in the ETs we're ending
up with :-(
I posted that the best ET from Wed. was a 9.8, and Ken Trough had asked:
Doesn't that mean that the Silver Bullet broke through the 100mph barrier
for street legal cars?? I realize that this was not a sanctioned NEDRA
event and that the times are probably not official, but how about some
timeslip details?? Drool.
Others have already addressed this, but I'll also reply. Ken, Wed. nights
at PIR are strictly 1/8 mile only, so the 9.8 was in the 1/8 mile, not the
1/4 mile. In that post, I had written:
Last night Jeffrey Bywater, im Brehm, and yours truly took the Silver
Bullet for shake down 1/8 mile runs to PIR...so his 1/8 mile times were
around the 10.0 - 10.2 second region, but once he figured out the linkage
thing and started to nail his shifts, things got better. The Silver
Bullet's best time was a 9.8 second run.
OK, back to last night's '1/4 mile' runs....As stated, the car runs a lot
slower than we had hoped for, with ETs never getting close to the 14
second range and in the high 15's with a 16.2 thrown in to make it sting a
little more for the 5 runs it made. The best ET was the last one of the
night at 15.695 @ 82.15 mph. Still, it generates tons of excitement at the
track. Jeffrey has turned into a good drag race driver and nearly nailed
the $50 award for a perfect reaction time with his .001! In fact, all of
his reaction times were super, at .001, .053, .027, .028, and .021,
pretty darn good for a newbie drag racer!
Even with tepid ETs, the race fans and fellow drivers all love this car.
Many have seen another little EV run low 13s and so know that electric
cars 'can' get the job done. One of the most fun races of the night, was
when another silver Datsun 280ZX pulled into the pit area right near our
camp. The guys had this Z Car, plus a pretty hot green Rabbit that was
running mid 13s. They immediately came over to see what our Z had under
the hood, and just about fell over when they saw those three electric
motors under there! We all became friends on the spot....very fun evening
with them.
I arranged with 'Big Jim' in the staging lanes to have the twin silver Zs
run against each other, and the crowd loved the grudge match. Out of the
hole, Jeffrey stuck it to 'em with the Silver Bullet lunging off the line,
tires squealing loudly, nose up high, and easily dusting the gassser Z
badly at first. Jeffrey banged 2nd and lit up the tires again, then
grabbed 3rd and was still pulling the straight six Z next to him. It
wasn't until the final leg of the race that the gasser Z was on cam and
humping hard as it finally blew past the Silver Bullet and on to a 14.7
second run, with the Silver Bullet only managing a 15.7...oh well. It was
great listening to the crowd's reaction to the way the electric Z had
initially accelerated out of the hole. The best part though, was when the
other Z driver came back to the pit area, his mouth going a million miles
per hour about the way our Z had embarrassed his off the line, "Geezzz,
that thing's got TORQUE! Geezzzz, it freaked me out. I mean, mannnnnn,
it's unreal!" He went on and on about the way it blew his car into the
bushes for a while, and he commented on how he didn't think his car could
catch ours as he saw the Silver Bullet's taillights most of the way down
the track. He and his crew spent a lot of time admiring the electric Z,
and they all seemed ready to make an electric drag racer of their
own....better watch out for these guys. It's really too bad we didn't have
someone there with a video camera to catch this classic Z battle.
We struggled to get the car fast through the 1/4 mile, and even tried
disconnecting one of its three motors to run on two motors...the ET went
down from a 15.9 to a better 15.7, but we all thought the difference was
most likely due to the batteries warming up with each run. We confirmed
this when we reconnected the third motor and ran a similar time the next
run. Before the last run, I checked the calibration of the master Raptor's
throttle solenoid and found it way off. Adjusted for best WOT (wide open
throttle), Jeffrey reported he finally saw the yellow current limit LED
lighting and the Z dropped 2 tenths off the ET to its best 15.695 @ 82.15
mph.
OK, what's wrong? We don't know for sure, but we do have our ideas on the
subject:
(1) When we got the car a few weeks ago, it had been left out in the
weather, was banged up a bit, and had cracked and in our opinion dangerous
rear tires that had sat deflated with all the car's weight crinkling the
sidewalls. Rudman stepped up and supplied us with his sticky BR Goodrich
TA drag radials, the same models I use on White Zombie, for us to try on
the Z. They are a far lower profile tire than the ones we pulled from the
car, but better in all other ways. Rudman had predicted that their smaller
diameter would limit the car's top end, and we think he was right...damn,
I owe him a dinner on the lost bet over this! With the same high quality
drag radials but in a different diameter, we're thinking that much taller
versions will really improve the top end to bring the car closer to the
14's and bring the 82 mph trap speed closer to 86 - 89 mph.
(2) The motors seem to be timed at neutral and just don't pull like they
should. On this, Rudman and I agree. Taking the triple motor configuration
apart, twisting the end bells, redrilling the bolt holes and reassembling
the affair would be time well spent. This change is probably the most
needed, and I feel it could push the car deep into the 14s, maybe even
into the high 13's.
(3) The suspension is really in need of attention. The car nearly scrapes
its rear bumper on launches and the nose takes on a 757 take-off effect.
Reworking spring rates and shock control would more than likely trim off a
few more tenths.
(4) Perhaps as much as 200 lbs. of weight can and should be removed from
the car.
All the above considered, it amazes me that this car ever managed its
world record best at 156V with its 14.77 ET....how did Father Time pull
that one off?
Everyone is attracted to this machine and we know it can get much faster
and quicker. I've got a great group of younger guys filled with EV
enthusiasm that I work with and have drug into this whole electric drag
racing scene, so with Tom True's permission and Father Time's involvement,
they can really help to get this thing into the fast lane again.
For now, it's back to White Zombie this Saturday. Tim and I have been
getting frustrated with time delays on everything, but we're working on
this. The delays did make it possible to play with the Silver Bullet for
the last two weeks :-) Marko will be getting the final metalwork done
that's needed for the major under-hood redesign I've got going on. The
aluminum driveline should be done in a week or so. Today, the two modules
that make up the 348V battery pack are being assembled and the 29
batteries will all be bolted in securely, when we receive the hold-down
brackets.
OK, off the computer and out the EV shop I go!
See Ya........John 'Plasma Boy' Wayland
-
--
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--- End Message ---
--- Begin Message ---
Hi-
First check the sc/f record 120v. 15.611, 84.03mph.
Thats with 2 strings of Exide Orbital's.
A little history:
Tom bought the three motor package from Bob Boyd,
it was 1/2 of the motor package from his dragster..
Dual 1200 Raptor's, 2 strings, 156v-u33 wheel chair batts.
Theback of the car sagged a lot so I told the spring poeple
that I had added 700 lbs to the rear axle, they made us new
springs which we instaled over the stock struts. This brought the
ride hieght level agian.This caused some wheel hop so a different
ratio set of strut shocks was instaled.
the next problem, about the third run down the track,the stock
clutch disk melted on to the flywheel, replaced with a 3200 lb.
Center Force Dual friction clutch. the next carnage was the stock diff.
It was replaced with a r200 from a 300zx, 4.11 gears which I believe
are still in the car.
Now we replaced the dual Raptors with a single T-Rex, whitch at 336v.
I promptly let the smoke out of at a stop sign.
Now it was time for a new battery pack, three strings of 16 ah Hawker's
feeding triple 1200 raptors. this was a good combination. It twisted off the
main shaft between the motors and the flywheel, instal stronger shaft.
The next failure was the 3200 clutch.The backing plate thisted 1/4 in. off
center and took out the trans. input shaft. We replaced the 3200 lb. clutch
with a3800 lb. one and the trans. Then a drive axle.
After an unhappy experience wiyh 4 strings SVR 14's we replaced them
with 2 strings of Exide Orbital's at 120v.
Along the way we managed to set several records in SC/D at 156v. and
the current record in SC/F.
The last time we had the motors rebuilt, I believe I advanced the brush
timing
to 10 degrees. I've gone through the motors several times and did'nt keep
notes.
My suggestion as to whats wrong; tire size, and check the ratio on rear
struts.
-F.T.
> [Original Message]
> From: John Wayland <[EMAIL PROTECTED]>
> To: <[email protected]>
> Date: 8/13/2005 9:13:41 AM
> Subject: Silver Bullet Electric Z Car 1/4 Mile Run Results
>
> Hello to All,
>
> OK, it's Saturday morning, the day after.....Last night the deadly trio
> of Tim, Jeffrey, and Plasma Boy returned to PIR with the Silver Bullet
> to see what we could squeeze out of it in the 1/4 mile as a follow up to
> last Wednesday night's 1/8 mile runs. We're having a lot of fun racing
> this whistling beast, but we're also a bit disappointed in the ETs we're
> ending up with :-(
>
> I posted that the best ET from Wed. was a 9.8, and Ken Trough had asked:
>
> > Doesn't that mean that the Silver Bullet broke through the 100mph
> > barrier for street legal cars?? I realize that this was not a
> > sanctioned NEDRA event and that the times are probably not official,
> > but how about some timeslip details?? Drool.
>
> Others have already addressed this, but I'll also reply. Ken, Wed.
> nights at PIR are strictly 1/8 mile only, so the 9.8 was in the 1/8
> mile, not the 1/4 mile. In that post, I had written:
>
> > Last night Jeffrey Bywater, im Brehm, and yours truly took the Silver
> > Bullet for shake down 1/8 mile runs to PIR...so his 1/8 mile times
> > were around the 10.0 - 10.2 second region, but once he figured out the
> > linkage thing and started to nail his shifts, things got better. The
> > Silver Bullet's best time was a 9.8 second run.
>
> OK, back to last night's '1/4 mile' runs....As stated, the car runs a
> lot slower than we had hoped for, with ETs never getting close to the 14
> second range and in the high 15's with a 16.2 thrown in to make it sting
> a little more for the 5 runs it made. The best ET was the last one of
> the night at 15.695 @ 82.15 mph. Still, it generates tons of excitement
> at the track. JeffrExcice ey has turned into a good drag race driver and
nearly
> nailed the $50 award forOrbital's a perfect reaction time with his .001!
In fact,
> all of his reaction times were super, at .001, .053, .027, .028, and
> .021, pretty darn good for a newbie drag racer!
>
> Even with tepid ETs, the race fans and fellow drivers all love this car.
> Many have seen another little EV run low 13s and so know that electric
> cars 'can' get the job done. One of the most fun races of the night, was
> when another silver Datsun 280ZX pulled into the pit area right near our
> camp. The guys had this Z Car, plus a pretty hot green Rabbit that was
> running mid 13s. They immediately came over to see what our Z had under
> the hood, and just about fell over when they saw those three electric
> motors under there! We all became friends on the spot....very fun
> evening with them.
> I arranged with 'Big Jim' in the staging lanes to have the twin silver
> Zs run against each other, and the crowd loved the grudge match. Out of
> the hole, Jeffrey stuck it to 'em with the Silver Bullet lunging off the
> line, tires squealing loudly, nose up high, and easily dusting the
> gassser Z badly at first. Jeffrey banged 2nd and lit up the tires again,
> then grabbed 3rd and was still pulling the straight six Z next to him.
> It wasn't until the final leg of the race that the gasser Z was on cam
> and humping hard as it finally blew past the Silver Bullet and on to a
> 14.7 second run, with the Silver Bullet only managing a 15.7...oh well.
> It was great listening to the crowd's reaction to the way the electric Z
> had initially accelerated out of the hole. The best part though, was
> when the other Z driver came back to the pit area, his mouth going a
> million miles per hour about the way our Z had embarrassed his off the
> line, "Geezzz, that thing's got TORQUE! Geezzzz, it freaked me out. I
> mean, mannnnnn, it's unreal!" He went on and on about the way it blew
> his car into the bushes for a while, and he commented on how he didn't
> think his car could catch ours as he saw the Silver Bullet's taillights
> most of the way down the track. He and his crew spent a lot of time
> admiring the electric Z, and they all seemed ready to make an electric
> drag racer of their own....better watch out for these guys. It's really
> too bad we didn't have someone there with a video camera to catch this
> classic Z battle.
>
> We struggled to get the car fast through the 1/4 mile, and even tried
> disconnecting one of its three motors to run on two motors...the ET went
> down from a 15.9 to a better 15.7, but we all thought the difference was
> most likely due to the batteries warming up with each run. We confirmed
> this when we reconnected the third motor and ran a similar time the next
> run. Before the last run, I checked the calibration of the master
> Raptor's throttle solenoid and found it way off. Adjusted for best WOT
> (wide open throttle), Jeffrey reported he finally saw the yellow current
> limit LED lighting and the Z dropped 2 tenths off the ET to its best
> 15.695 @ 82.15 mph.
>
>
> OK, what's wrong? We don't know for sure, but we do have our ideas on
> the subject:
>
> (1) When we got the car a few weeks ago, it had been left out in the
> weather, was banged up a bit, and had cracked and in our opinion
> dangerous rear tires that had sat deflated with all the car's weight
> crinkling the sidewalls. Rudman stepped up and supplied us with his
> sticky BR Goodrich TA drag radials, the same models I use on White
> Zombie, for us to try on the Z. They are a far lower profile tire than
> the ones we pulled from the car, but better in all other ways. Rudman
> had predicted that their smaller diameter would limit the car's top end,
> and we think he was right...damn, I owe him a dinner on the lost bet
> over this! With the same high quality drag radials but in a different
> diameter, we're thinking that much taller versions will really improve
> the top end to bring the car closer to the 14's and bring the 82 mph
> trap speed closer to 86 - 89 mph.
>
> (2) The motors seem to be timed at neutral and just don't pull like
> they should. On this, Rudman and I agree. Taking the triple motor
> configuration apart, twisting the end bells, redrilling the bolt holes
> and reassembling the affair would be time well spent. This change is
> probably the most needed, and I feel it could push the car deep into the
> 14s, maybe even into the high 13's.
>
> (3) The suspension is really in need of attention. The car nearly
> scrapes its rear bumper on launches and the nose takes on a 757 take-off
> effect. Reworking spring rates and shock control would more than likely
> trim off a few more tenths.
>
> (4) Perhaps as much as 200 lbs. of weight can and should be removed from
> the car.
>
> All the above considered, it amazes me that this car ever managed its
> world record best at 156V with its 14.77 ET....how did Father Time pull
> that one off?
>
> Everyone is attracted to this machine and we know it can get much faster
> and quicker. I've got a great group of younger guys filled with EV
> enthusiasm that I work with and have drug into this whole electric drag
> racing scene, so with Tom True's permission and Father Time's
> involvement, they can really help to get this thing into the fast lane
> again.
>
> For now, it's back to White Zombie this Saturday. Tim and I have been
> getting frustrated with time delays on everything, but we're working on
> this. The delays did make it possible to play with the Silver Bullet for
> the last two weeks :-) Marko will be getting the final metalwork done
> that's needed for the major under-hood redesign I've got going on. The
> aluminum driveline should be done in a week or so. Today, the two
> modules that make up the 348V battery pack are being assembled and the
> 29 batteries will all be bolted in securely, when we receive the
> hold-down brackets.
>
> OK, off the computer and out the EV shop I go!
>
> See Ya........John 'Plasma Boy' Wayland
>
>
> -
--- End Message ---
--- Begin Message ---
At 8:28 PM -0700 8/13/05, Rush wrote:
From: "Ryan Stotts" <[EMAIL PROTECTED]>
Is 170 volts the absolute limit at all rpms? How does Netgain get 192
from theirs?
Is that true? For a 9" ADC motor the limit is 170 vdc that you can
put into it? What happens after that? I plan to do a 180 vdc pack...
For street use I suggest you set the motor voltage limit on your
Zilla to 150 Volts. That's pretty safe.
In my testing with video cameras on the brushes and meters I've found
170 Volts to be a good number for drag racing a well broken 8" or 9"
ADC motor.
The 150V volt limit will not really drop the maximum power from your
180V pack since at full power it sags down to there anyway. The
limit just protects your motor at lighter loads.
hth,
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
Really interesting idea (hub motors), but even at 3000 watts per motor if I
could a motor on all four would barely be more powerful than a single ETEK (or
other pancake motor).
I am trying to figure out if there is anything between the 20 lb ETEK and the
100 pound Advance, maybe in the 10 hp continuous.
Anyone come across good transaxles for a simple system. The GETRAG AMT 431
looks promising (27 lbs, made for 60 hp) it weighs 27 lbs. But I haven't
figured if the motor/tranmission connection could be efficiently done. It would
not be possible using the ETEK (not enough clearance from shaft, something
tricky would have to be done).
1000 lb chassis, light enough to consider low weight motor options ...
Thoughts?
Message-ID: <[EMAIL PROTECTED]>
From: "Roy LeMeur" <[EMAIL PROTECTED]>
To: [email protected]
Subject: Re: FW: New EV - Question
Date: Fri, 12 Aug 2005 21:04:58 -0700
Mime-Version: 1.0
Content-Type: text/plain; format=flowed
>I can dream, can't I? Besides, a small enough vehicle, more like a
>motorcycle, might be able to find an acceptable wheel motor.
I think that the EVT hubmotor has lots of potential application in something
like this.
http://www.electricmotorsport.com/PARTS/parts.htm
http://www.electricmotorsport.com/PARTS/EvtSpecs.htm
Three on a light EV could work well.
.
Roy LeMeur
Olympia 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
EV Parts/Gone Postal Photo Galleries:
http://www.casadelgato.com/RoyLemeur/page01.htm
--- End Message ---
--- Begin Message ---
Propolyne Glycol is a good heat transfer liquid and perfectly safe. You
could circulate it thru plastic tubes imbedded just under the upholstry. I
built a system for a covert surveillence van once using this stuff
circulated thru a modified AC underdash evaporator and cooled by a coil in a
stainless cooler filled with ice. Worked great. David Chapman.
----- Original Message -----
From: "Dave" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, August 04, 2005 3:08 PM
Subject: Re: thermally conductive gel
There is a thermal paste that is used to join heat sinks/fans to
processors in computers. You could try that.
With enough patience,
you can milk a porcupine
David C. Wilker Jr.
USAF (RET)
----- Original Message -----
From: "brian baumel" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, August 04, 2005 2:49 PM
Subject: thermally conductive gel
hello all,
does anyone have a suggestion for thermally conductive
gel? my idea is to take a car seat and change all or
most of the surface area that is contacting the person
to a thermally conductive gel. tubes running through
the gell will distribute cold, for lack of any other
word, from a peltier pump to the person. I'm just not
sure where to obtain or what type of gel to use. any
suggestions?
Brian B.
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
Rich Rudman and Dennis Berube can tell you all you need to know about
setting up a motor / generator dyno. They have both built similar dyno
setups, albeit on a larger scale. Good luck David Chapman.
----- Original Message -----
From: "M.G." <[EMAIL PROTECTED]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Saturday, August 13, 2005 3:14 PM
Subject: Motor dynometer
I want to do some testing on my forklift motor that will EVentually land
in my Audi as a converted vehicle.
I have taken some voltage measurements on some lift trucks at work but my
coworkers dont seem to understand what I am doing so I want to avoid that
as much as possible.
What I need is a Dynamometer I have an 11" GE motor in two configurations
, one is a separately excited motor and the other is a series motor. If I
connect the two motors together what should I use for a suitable load on
the series motor? I am going to use the sem motor in the car.
Would it be possible to connect the series motor to the battery pack I am
running the sem motor from as a suitable load like a regen setup? I know
this sounds like perpetual motion but I know that is not possible, I just
want a dyno. If possible any suggestions would be appreciated.
Mike G.
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Hey FT, this is a great post! It lets others on the list know what we go
through in building high performance electric drag cars. I sometimes get the
feeling that some people think that you can just go buy a Zilla and a couple
motors and a bunch of batteries and that is all there is to it. Your post
definitely dispels thoughts of it being an easy road. Thanks for your post.
I'll bet if John Wayland wrote the entire story of the incarnations of the
"White Zombie" it would be similar. I know for a fact that the story of the
"Maniac Mazda" is quite similar.
Roderick Wilde
"Suck Amps EV Racing"
www.suckamps.com
----- Original Message -----
From: <[EMAIL PROTECTED]>
To: <[email protected]>; <[email protected]>
Sent: Saturday, August 13, 2005 9:15 PM
Subject: RE: Silver Bullet Electric Z Car 1/4 Mile Run Results
Hi-
First check the sc/f record 120v. 15.611, 84.03mph.
Thats with 2 strings of Exide Orbital's.
A little history:
Tom bought the three motor package from Bob Boyd,
it was 1/2 of the motor package from his dragster..
Dual 1200 Raptor's, 2 strings, 156v-u33 wheel chair batts.
Theback of the car sagged a lot so I told the spring poeple
that I had added 700 lbs to the rear axle, they made us new
springs which we instaled over the stock struts. This brought the
ride hieght level agian.This caused some wheel hop so a different
ratio set of strut shocks was instaled.
the next problem, about the third run down the track,the stock
clutch disk melted on to the flywheel, replaced with a 3200 lb.
Center Force Dual friction clutch. the next carnage was the stock diff.
It was replaced with a r200 from a 300zx, 4.11 gears which I believe
are still in the car.
Now we replaced the dual Raptors with a single T-Rex, whitch at 336v.
I promptly let the smoke out of at a stop sign.
Now it was time for a new battery pack, three strings of 16 ah Hawker's
feeding triple 1200 raptors. this was a good combination. It twisted off
the
main shaft between the motors and the flywheel, instal stronger shaft.
The next failure was the 3200 clutch.The backing plate thisted 1/4 in. off
center and took out the trans. input shaft. We replaced the 3200 lb.
clutch
with a3800 lb. one and the trans. Then a drive axle.
After an unhappy experience wiyh 4 strings SVR 14's we replaced them
with 2 strings of Exide Orbital's at 120v.
Along the way we managed to set several records in SC/D at 156v. and
the current record in SC/F.
The last time we had the motors rebuilt, I believe I advanced the brush
timing
to 10 degrees. I've gone through the motors several times and did'nt keep
notes.
My suggestion as to whats wrong; tire size, and check the ratio on rear
struts.
-F.T.
--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.338 / Virus Database: 267.10.8/71 - Release Date: 8/12/2005
--- End Message ---
--- Begin Message ---
M.G. wrote:
>
> I am not worried about the hp and torque. I know the motor will provide
> enough. What I will be trying to accomplish is a high voltage controller
> for the sem motor.
> It is set up for 48 volts from the factory, I would like to modify it to
> run at approx 150 volts.
> Mike G.
>
> M.G. wrote:
>
> >> If I connect the two motors together what should I use for
> >> a suitable load on the series motor?
> >
> >
>
> What method will you use to measure the hp/tq?
One rather sneaky way to measure a motor's torque and horsepower is to
run it no-load and just measure its instantaneous rpm. Its own
rotational inertia provides the load. Better still, add an inertial load
like a flywheel.
Run the motor at various fixed speeds, and record the voltage and
current it takes. This is the no-load power consumption.
Now bring the motor up to its maximum rpm, and quickly shut off the
power. Record the rpm versus time as it coasts to a stop.
>From these two sets of data, you can calculate the torque needed to
overcome its own friction and windage at any speed.
Now you can switch the motor from off to full speed. The controller will
automatically use its current limiting to accellerate the motor as fast
as it can. Again, record the rpm versus time as it accellerates.
>From this data you can calculate the horsepower being produced at every
speed. The horsepower over that required just to maintain speed is being
used to accellerate the motor (and flywheel) rotational inertia, and is
easy to calculate.
--
*BE* the change that you wish to see in the world.
-- Mahatma Gandhi
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
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>> Is 170 volts the absolute limit at all rpms? How does Netgain
>> get 192 from theirs?
Rush wrote:
> Is that true? For a 9" ADC motor the limit is 170 vdc that you
> can put into it? What happens after that? I plan to do a 180 vdc
> pack...
Semiconductors have an absolute voltage limit; like a chain that is
either carrying the entire load, or suddenly breaks. For example, a 100
volt diode or transistor may have a real breakdown voltage of 120 volts.
At 119v it works perfectly normally. At 120v it suddenly fails shorted!
But motors are not like that. They are more like rubber bands that
stretch rather than break. They do not have any clear maximum voltage
limit. No matter what voltage you are at, you can increase it a little
more. All that happens is that the higher the voltage, the shorter the
motor's life.
That's how we "get away" with putting 120v on a 48v motor. The original
motor was expected to last 20 years in a forklift being operated 8 hours
a day, 5 days a week, 50 weeks a year. That's over 40,000 hours!
But we put it in a car. We will be happy if it lasts 100,000 miles. But
at an average of 50 mph, that's only 2000 hours. Since we can tolerate
20:1 shorter life, we can raise the voltage drastically and the motor
will *still* last that long. Experimentally, we've found that this 48v
motor can stand 120v for 2000 hours.
You can go even higher if you don't mind even shorter life. You will
start having "little" problems, like places where there isn't enough air
gap between bare conductors. But you can add insulation to beef up these
weak places. You can tweak the brush timing, to optimize it for the
higher voltages. You can limit the current at the higher voltages, since
it's the combination of high voltage *and* high current that causes most
of the damage.
Finally, remember that the controller rarely applies the full pack
voltage to the motor. It only does so at full throttle when the motor
rpm is high enough so it draws less than the controller's current limit.
This is so much horsepower that you won't be operating there for more
than a matter of seconds at a time.
--
*BE* the change that you wish to see in the world.
-- Mahatma Gandhi
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
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--- Begin Message ---
Killer links, thanks! I could see myself on a recumbent that has 30+mph and 100
mile range
for going to/from work. My job is 28miles away and I can get there without
getting on the
highway without much trouble here in Florida.
I really need to look into something like this. Gas, even for my 4cyl Honda, is
getting
way expensive. Plus, it has 262,000 miles and things are starting to break. A
new
commuting vehicle is in my near future. Since there is no ins. requirement for
motorcycles
here, this would be a cheap ride...
--
joe
> -----Original Message-----
> From: Lawrence Rhodes [mailto:[EMAIL PROTECTED]
> Sent: Saturday, August 13, 2005 1:13 PM
> To: [email protected]
> Subject: Re: New EV bikes?
>
> http://www.electric-bikes.com/EZ-Hawk.htm Incase you missed it. LR....
> -----Original Message-----
> From: Lawrence Rhodes [mailto:[EMAIL PROTECTED]
> Sent: Saturday, August 13, 2005 1:36 PM
> To: [email protected]
> Subject: Re: New EV bikes?
>
> http://www.electric-bikes.com/others.htm#Betterbikes another URL. Very
> interesting. LR>..........
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--- Begin Message ---
Bruce Weisenberger wrote:
>Unfortunately the US government put the limits to
>E-Bikes. Issues include safety of riders on bicycles.
>Now make it into a scooter or motorcycle with all the
>lights and federally required safety gear and we'd
>have something. FYI e-bikes are neat but in Arizona
>they are not permitted on bike paths or sidewalks. Nor
>are they allow on any street that is rated over 35
>MPH. Limits are placed on bike to not be able to have
>motors that develop over 500W or travel over 25 MPH
>with Gas, electric or otherwise.
>
>
>
>
>
Do you know what the New York regulations are? I suppose they are
probably different. I found this NYS assembly bill, though I don't know
if it is now a law or not:
<http://assembly.state.ny.us/leg/?bn=A00071>
Might anyone know how I determine if it has passed? The website doesn't
seem to give me any help to figure that part out.
One thing I see under the status is this:
01/06/05 referred to transportation
03/15/05 reported referred to codes
04/19/05 reported
04/28/05 advanced to third reading cal.306
05/02/05 passed assembly
05/02/05 delivered to senate
05/02/05 REFERRED TO TRANSPORTATION
I suppose it is stuck in "transportation" whatever that is.. a committee?
--
Martin Klingensmith
http://wwia.org/
http://nnytech.net/
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One of the failure issues on motor is the insulation- either winding to
winding or winding to rotor.
Insulation lifetime is a complex equation but there are a number of easy
to understand factors. The first is high temps are very hard on
insulation. The cooler you can run the motor, the better. The second
is high dv/dt rates are very hard on insulation, perhaps more so that
the peak value of the voltage. Unfortunately, the PWM which makes a
motor so easy to manage is a big problem here. So if you had a 144v
pack that you wanted to run a motor at 48v average, not only are you
still hitting the insulation at 144v peak, the positive and negative
edges of every PWM cycle are done very sharp for simple and efficient
switching but this is additional stress.
Brush and slip ring/commutator failure are probably going to happen
first so it may never come up. I don't know much about how to estimate
reliability on those components.
Don't read this as me saying there's anything wrong with PWM, it's
necessary unless you can get ahold of an extremely expensive dc/dc
converter. I think the best thing is to just take the word of people
doing it in the field, maybe consider keeping your pack voltage only as
high as needed to do the job, and keep the motor cool.
Danny
Lee Hart wrote:
You can go even higher if you don't mind even shorter life. You will
start having "little" problems, like places where there isn't enough air
gap between bare conductors. But you can add insulation to beef up these
weak places. You can tweak the brush timing, to optimize it for the
higher voltages. You can limit the current at the higher voltages, since
it's the combination of high voltage *and* high current that causes most
of the damage.
--- End Message ---
--- Begin Message ---
On Aug 13, 2005, at 6:30 PM, Michaela Merz wrote:
While driving from work today (around 95 degrees outside) pulling about
110 Amps, my car suddenly hesitated with some weird whining noise
coming
from the front.
Sounds like a complaining Curtis controller. They drop frequency when
hot and cut back amps. The Curtis 1221B drops to 1 kHz.
Try to drive in the lowest gear you can. This will maximize motor
voltage and minimize motor current. A Curtis 1221 is only good for 150
amps continuous, perhaps less at 95 F. This limit applies to motor
current which is usually higher than the battery current.
Paul "neon" G.
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--- Begin Message ---
The recent discussion regarding getting 120VAC from
the pack got me thinking about some options.
What if we generate square wave (modified sine wave)
straight from pack voltage and feed this to a variac
or a bulk/boost auto-transformer to get the AC voltage
we want? This would be pretty easy to do, wouldn't
it?
Ed Ang
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--- Begin Message ---
Just wondering if anyone has a charger profile for the Brusa NLG412 for
a 144-Volt pack of Deka Dominators (aka Sonnenschein). It turns out
that my E-10 pickup's charger has a profile in it that tops out at 15
volts per module, which is (AFAIK) too high for the Deka Dominators.
IIRC, the Dekas want to finish off at no more than 14 volts per module.
I had assumed (incorrectly) that when Solectria gave the Bureau of Land
Management the instructions for changing this truck over from Hawkers to
Dominators, they had also reprogrammed the battery charger. I suppose
this is why my pack didn't last as long as I had expected.
Anywho, if anyone can point me to a location where I can grab a copy of
this charging profile, or email me a copy of it directly, I'd appreciate
it. I suspect the Hawker profile in my truck also probably has
different temperature compensation etc. as well so I don't just want to
dial down the voltage.
Thanks!
-Tom
--
Thomas Hudson
http://portdistrict5.org -- 5th District Aldermanic Website
http://portev.org -- Electric Vehicles, Solar Power & More
http://portgardenclub.org -- Port Washington Garden Club
http://portlightstation.org -- Light Station Restoration
http://klanky.com -- Animation Projects
--- End Message ---
--- Begin Message ---
Lawrie, Robin wrote:
> What are the advantages/disadvantages to the lower voltage system?
I'll assume you want to keep the same range and same peak power; then
you need the same WEIGHT of batteries no matter how you wire them. The
same batteries can all be wired in parallel, all in series, or any
series-parallel combination in between, and will all produce the same
range, same efficiency, and same peak power.
You need to pick the motor and controller to match the pack voltage.
Obviously a lower-voltage motor and controller must be rated at higher
current to have the same power and horsepower. But there is
fundamentally no change in the motor; it can be wound for any voltage
and current with essentially no effect on its size, weight, cost,
efficiency, horsepower, torque, or rpm.
The controller also needs to be chosen to match the pack voltage. The
commonly available transistors favor voltages from about 50v to 300v.
MOSFETs are preferred at the low-voltage end, and IGBTs at the high
voltage end. But you can also use SCRs or bipolar transistors, or even
contactors, none of which care much about the exact voltage within this
range.
What all this says is there is no "big" reason to pick a high-voltage or
low-voltage system. So what are the "feathers on the scale" that tilt a
designer toward a high-voltage or low-voltage system?
1. Availability; what's easy to get? Low-voltage DC motors are more
common. High-voltage AC motors are more common.
2. Lower voltages are safer.
3. Lower voltages mean fewer batteries of higher amphour capacity,
which tend to be cheaper.
4. Lower voltages have less wiring and fewer connections, which
tends to be easier to build.
5. Lower voltages favor contactor controllers, which are the cheapest.
6. Higher voltages can use smaller wiring, which tends to be cheaper.
7. Higher voltages favor IGBTs, which tend to be cheaper than MOSFETs.
8. Commonality: Let your system voltage be chosen based on stuff you
already have or can get cheap, like a used 48v forklift motor or a
DC/DC converter that is really a 120vac power supply but happens
to work on 144vdc.
9. Reliability. The fewer the parts, the more reliable a system gets.
This favors lower-voltage systems, which have fewer parts (mainly
batteries and interconnects).
10. Use what everybody else does. There is a tendency to copy what
others have done, on the assumption that they know what they
are doing. This can save time lost to experimenting, debugging,
and other "surprises".
--
*BE* the change that you wish to see in the world.
-- Mahatma Gandhi
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
