EV Digest 3362
Topics covered in this issue include:
1) Re: Cheap magnachargers on eBay
by "Diana Trevino" <[EMAIL PROTECTED]>
2) RE: Carbon pile? and blowers
by "Roger Stockton" <[EMAIL PROTECTED]>
3) RE: Carbon pile? and blowers
by David Brandt <[EMAIL PROTECTED]>
4) ID ltpiypqqesp... thanks
by [EMAIL PROTECTED]
5) RE: Carbon pile? and blowers
by "Andre Blanchard" <[EMAIL PROTECTED]>
6) Re: Carbon pile? and blowers
by Rich Rudman <[EMAIL PROTECTED]>
7) RE: Dyno equipment WAS: Carbon pile? and blowers
by Richard Bebbington <[EMAIL PROTECTED]>
8) Re: High Voltage DC/DC
by Victor Tikhonov <[EMAIL PROTECTED]>
9) Re: Carbon pile? and blowers
by Rich Rudman <[EMAIL PROTECTED]>
10) seeking: an escoot that can fold for travel
by Bruce EVangel Parmenter <[EMAIL PROTECTED]>
11) Re: Carbon pile? and blowers
by Victor Tikhonov <[EMAIL PROTECTED]>
12) Re: seeking: an escoot that can fold for travel
by Christopher Robison <[EMAIL PROTECTED]>
13) Re: seeking: an escoot that can fold for travel
by Rod Hower <[EMAIL PROTECTED]>
14) Re: ampabout ... in-security
by Bruce EVangel Parmenter <[EMAIL PROTECTED]>
15) Re: Carbon pile? and blowers
by "Roland Wiench" <[EMAIL PROTECTED]>
16) Ebay motors, brush DC and BLDC
by Rod Hower <[EMAIL PROTECTED]>
17) Re: Ebay motors, brush DC and BLDC more
by Rod Hower <[EMAIL PROTECTED]>
18) Re: Dyno
by Martin Jackson <[EMAIL PROTECTED]>
19) Re: Dyno
by Otmar <[EMAIL PROTECTED]>
20) Re: Cheap magnachargers on eBay
by "David McAlister" <[EMAIL PROTECTED]>
21) Tour de Sol & BEVs
by Jim Coate <[EMAIL PROTECTED]>
22) Re: Panasonic Prizmatic batteries
by Seth <[EMAIL PROTECTED]>
23) Re: Dyno
by Rich Rudman <[EMAIL PROTECTED]>
24) Re: Cheap magnachargers on eBay
by Lee Hart <[EMAIL PROTECTED]>
25) Re: seeking: an escoot that can fold for travel
by "BORTEL" <[EMAIL PROTECTED]>
--- Begin Message ---
If one could get to the batteries, that would be a good idea.
----- Original Message -----
From: "Jim Coate" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Tuesday, February 17, 2004 10:53 AM
Subject: Re: Cheap magnachargers on eBay
> I don't know how the batteries are laid out, but is there a safe &
> practical way to disconnect them at strategic points to break into
> smaller groups of say 48-96 volts each? Then go around with a more tame
> charger and work on one block at a time.
>
> If I understand the situation, the batteries are in unknown condition
> but likely less then good. So really need to be checking them one by one
> anyway to see what is happening.
>
>
> Diana Trevino wrote:
> >I am trying to build a 400 volt charger to charge the batteries
> >directly. Just a very basic charger, non-isolated, non-automatic,
> >just some 400 VDC to charge the batterys in the two Electricars
> >and see where we stand.
>
>
>
> _________
> Jim Coate
> 1970's Elec-Trak
> 1992 Chevy S-10 BEV
> 1997 Chevy S-10 NGV
> http://www.eeevee.com
>
>
--- End Message ---
--- Begin Message ---
Joe Smalley [mailto:[EMAIL PROTECTED] wrote:
> I think he was looking for something like
> http://www.sensotec.com/pdf/9300.pdf
This particular one wouldn't do, since it tops out at 2500RPM.
> or http://www.sensotec.com/pdf/6200.pdf
Now, this looks better, with the 30,000 in-lb (2500 ft-lb) modle good
for 10,000RPM. But accuracy is 0.25% to 1% of full scale (probably
still fine, but worse than cheaper systems).
> There is a large selection at http://lebow.com/pfull.htm.
>
> One of the neater models that caught my attention was
> http://lebow.com/prodfolder/2000.pdf . It does digital
> sampling on the transducer at 26 kHz and uses digital
> telemetry to send the data to a pickup loop. The transducer
> has a 3 dB rolloff at 2 kHz. Accuracy is quoted at 0.01%.
Hmmm... 1000 ft-lbs @ 13,000RPM or 1500-2000 ft-lbs at 11,000RPM looks
good. But the total accuracy spec I read is <=0.25%, not 0.01%. Did I
miss something?
> The specifications make it look expensive.
Yep.
David Brandt [mailto:[EMAIL PROTECTED] wrote:
> All the digital stuff will drive the price up a bit. IMHO, a
> simple strain gage based torque sensor and a good panel meter
> that will output RS232 to the computer is just as good, and
> it can be had relatively inexpensively. Expect to pay at
> least $5000 total, though.
Why expect to pay at least $5000? A lever arm and this $1300 force
guage with LCD readout and RS232/485 data logging makes a dyno that is
every bit as accurate as these expensive wireless systems and doesn't
have an RPM limit. For example:
> > > <http://www.dqplus.com/edx.htm>
> > >
> > > EDx-2.5k 2500lb-ft, 0.1%, 2 samples/sec, RS232 & 485. $1315.
> This is assuming you want to measure torque while the system
> is turning. The way some others were talking, it sounded like
> you only needed to measure it at stall.
>
> Can you give us a clearer idea of what the system looks like
> (for those of us who are clueless as to how dynos are set
> up)? What do you need to measure, when, and under what
> conditions? And, of course, how much do you want to spend?
Rich will want to measure torque vs RPM from 0 to infinity (OK, maybe
6500-8000RPM ;^).
It sounds like he is coupling the motor under test to a generator
(alternator), and using the generator to load the motor down. He could
measure the torque using a sensor to measure torsional twist in the
shaft between the two, or using a simple lever arm and force sensor to
measure the torque reaction of either the generator or motor case. It
seems to me that the cheapest approach is to mount the load-absorbing
generator so that its case is free to rotate except as resisted by the
force guage.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Roger Stockton wrote
> It sounds like he is coupling the motor under test to a generator
(alternator), and using the generator to load the motor down. He could
measure the torque using a sensor to measure torsional twist in the shaft
between the two, or using a simple lever arm and force sensor to measure the
> torque reaction of either the generator or motor case. It seems to me
that the cheapest approach is to mount the load-absorbing generator so that
its case is free to rotate except as resisted by the force guage.
>
> Cheers,
>
> Roger.
>
Oh, NOW I get it. You are proposing the lever/load cell at the case
reaction on the generator. I kept picturing it on the shaft, which would
require stalling the motor. This does make sense, and would be cheap and
easy to do. For around $1500 you can get a nice load cell, a panel meter to
do all the excitation (and scaling, though you could do this at the computer
end, too) and output RS232, and probably some software to boot.
I agree. This is the cheapest way to do it. This is kind of like the
measurement method for flow rate I saw one time on a test bench for low flow
rate pumps - they pumped water into a calibrated box that was suspended at
one edge by a hinge. A load cell supported the other edge. By reading the
reaction (actually only the rate of change of reaction was needed), they
could calculate flow rate.
I was presuming a torguemeter with a rotating shaft in-line with the motor
and generator shafts. That sort of load cell is more pricey - see the links
I posted originally. I believe the omega one was $4150 or so, but it "only"
went to 10,000 in-lb (833 ft-lb). They are available from other
manufacturers for higher torque levels.
--- End Message ---
--- Begin Message ---
------------------ Virus Warning Message (on pollux)
Found virus WORM_BAGLE.B in file uaisntbjb.exe
The file is deleted.
---------------------------------------------------------
Yours ID ysnojow
--
Thank
------------------ Virus Warning Message (on pollux)
uaisntbjb.exe is removed from here because it contains a virus.
---------------------------------------------------------
--- End Message ---
--- Begin Message ---
To eliminate alignment problems it would be best if the generator case were
free to rotate around the same axis as the shaft. If the generator has a
long enough main shaft and a tail shaft then mounting could be as easy as
set of pillow block bearings on these shafts. The torque arm could then be
bolted anyplace on the generator case. Mounted this way the bearings would
be a small source of error in the torque signal, but I do not think it would
be enough to worry about.
Andre' B.
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of David Brandt
Sent: Tuesday, February 17, 2004 12:50 PM
To: '[EMAIL PROTECTED]'
Subject: RE: Carbon pile? and blowers
> Roger Stockton wrote
>
> > It sounds like he is coupling the motor under test to a generator
> > (alternator), and using the generator to load the motor down. He could
> measure the torque using a sensor to measure torsional twist in the shaft
> between the two, or using a simple lever arm and force sensor to measure
> the
>
> > torque reaction of either the generator or motor case. It seems to me
> that the cheapest approach is to mount the load-absorbing generator so
> that
> its case is free to rotate except as resisted by the force guage.
> >
> > Cheers,
> >
> > Roger.
> >
>
> Oh, NOW I get it. You are proposing the lever/load cell at the case
> reaction on the generator. I kept picturing it on the shaft, which would
> require stalling the motor. This does make sense, and would be cheap and
> easy to do. For around $1500 you can get a nice load cell, a panel meter
> to
> do all the excitation (and scaling, though you could do this at the
> computer
> end, too) and output RS232, and probably some software to boot.
<< snip >>
--- End Message ---
--- Begin Message ---
Roger Stockton wrote:
>
> Joe Smalley [mailto:[EMAIL PROTECTED] wrote:
>
> > I think he was looking for something like
> > http://www.sensotec.com/pdf/9300.pdf
>
> This particular one wouldn't do, since it tops out at 2500RPM.
>
> > or http://www.sensotec.com/pdf/6200.pdf
>
> Now, this looks better, with the 30,000 in-lb (2500 ft-lb) modle good
> for 10,000RPM. But accuracy is 0.25% to 1% of full scale (probably
> still fine, but worse than cheaper systems).
>
> > There is a large selection at http://lebow.com/pfull.htm.
> >
> > One of the neater models that caught my attention was
> > http://lebow.com/prodfolder/2000.pdf . It does digital
> > sampling on the transducer at 26 kHz and uses digital
> > telemetry to send the data to a pickup loop. The transducer
> > has a 3 dB rolloff at 2 kHz. Accuracy is quoted at 0.01%.
>
> Hmmm... 1000 ft-lbs @ 13,000RPM or 1500-2000 ft-lbs at 11,000RPM looks
> good. But the total accuracy spec I read is <=0.25%, not 0.01%. Did I
> miss something?
>
> > The specifications make it look expensive.
>
> Yep.
>
> David Brandt [mailto:[EMAIL PROTECTED] wrote:
>
> > All the digital stuff will drive the price up a bit. IMHO, a
> > simple strain gage based torque sensor and a good panel meter
> > that will output RS232 to the computer is just as good, and
> > it can be had relatively inexpensively. Expect to pay at
> > least $5000 total, though.
>
> Why expect to pay at least $5000? A lever arm and this $1300 force
> guage with LCD readout and RS232/485 data logging makes a dyno that is
> every bit as accurate as these expensive wireless systems and doesn't
> have an RPM limit. For example:
>
> > > > <http://www.dqplus.com/edx.htm>
> > > >
> > > > EDx-2.5k 2500lb-ft, 0.1%, 2 samples/sec, RS232 & 485. $1315.
>
> > This is assuming you want to measure torque while the system
> > is turning. The way some others were talking, it sounded like
> > you only needed to measure it at stall.
> >
> > Can you give us a clearer idea of what the system looks like
> > (for those of us who are clueless as to how dynos are set
> > up)? What do you need to measure, when, and under what
> > conditions? And, of course, how much do you want to spend?
>
> Rich will want to measure torque vs RPM from 0 to infinity (OK, maybe
> 6500-8000RPM ;^).
>
> It sounds like he is coupling the motor under test to a generator
> (alternator), and using the generator to load the motor down. He could
> measure the torque using a sensor to measure torsional twist in the
> shaft between the two, or using a simple lever arm and force sensor to
> measure the torque reaction of either the generator or motor case. It
> seems to me that the cheapest approach is to mount the load-absorbing
> generator so that its case is free to rotate except as resisted by the
> force guage.
>
> Cheers,
>
> Roger.
Well simple and cheap non contact torque sensors... are not in the
cards....
I am looking to do this for about a Grand. At $25K I can do a LOT of
machining and hardware and software delvelopment.
SoI will be figuring out rotation motor mounts... and lever arms, just
like I was hoping I didn't have to.
The setup right now is a Advanced 8 incher with the movable brush head
Drive shafted(Thanks to John Wayland) to a very abused Advanced DC 9
incher.
The armature of the 9 is feed to a load bank, and the field is in series
ahead of the complete 8 incher. As you ask for more amps on the 8 you
get more loading on the 9. It's very controllable, and a bit in the
negative feedback mode. No clangs and bangs, but it really puts the
grunt onto the motors, They Moan as they load down. I have had the NiCr
hot, but not yet incandesent.
Dennis B does the same thing measuring his output watts very carfully.
He controlls the amps and volts into the machine, and watches the output
to the watt. This will be a great start for me. I still want rpm and
torque, but not having it is NOT a show stopper.
I want locked rotor to 8000 rpm. higher later maybe.
I do have a 25 Kw 208 3 phase alternator good to 8K and a 65Kw 208 3
phase aircraft alsternator good to 6400 rpm. the 65 Kw makes the 9
incher look small.
--
Rich Rudman
Manzanita Micro
www.manzanitamicro.com
1-360-297-7383,Cell 1-360-620-6266
--- End Message ---
--- Begin Message ---
This reminded me of something I saw in one
of our big electronics catalogues here in
the UK ( RS Components )
I can't remember the manufacturer
( haven't got an RS catalogue here at home )
but a basic description goes like this:
Imagine the load you're turning and your
driving shaft are arranged in-line.
Joining them together are two coupling pieces,
connected together with a reinforced rubber
tube. The tube has some lines printed on it,
along the tube's axis -
- the centre line is straight, but the others
are slightly skewed, getting more skewed as
you get towards the edge of the group of lines.
To read the torque, you use a strobe light
like those used for timing ICE cars. Get the
strobe in sync with the rotating assembly, so
the line appears stationary.
Look for which line is straightest - that tells
you how much the tube has twisted, and so
the torque.
Not hard-realtime, but cheap! ;-)
Plus it doubles as a shock-absorbing coupler.
You can find it on RS's website, go
to Products,
Mechanical,
Power Transmission Components,
Motor Couplings
and click on EuroFlex
P.S. , I just found out they're made by Gates
maybe they have higher-torque variants that RS
don't list
H.T.H.
Richard Bebbington
electric Mini pickup
--- End Message ---
--- Begin Message ---
Yes, BRUSA makes about 100 kW DC-DC, about the size of PFC-20.
I saw it on their bench table. It's more than you'd need for
DC-DC, intended to provide continuous power for drive system
while input fluctuates a lot (mainly FC application).
Of course, they have no problem producing less powerful
converters, just not interested.
Seth wrote:
>
> Brusa and Solectria both make them in different voltages, power levels
> and isolated or not. I think Brusa offers more options.
> > This is a question for you power electronics gurus out
> > there:
> >
> > Does anyone know a manufacturer that makes a high
> > voltage and high power DC/DC converter ?
> >
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
Andre Blanchard wrote:
>
> To eliminate alignment problems it would be best if the generator case were
> free to rotate around the same axis as the shaft. If the generator has a
> long enough main shaft and a tail shaft then mounting could be as easy as
> set of pillow block bearings on these shafts. The torque arm could then be
> bolted anyplace on the generator case. Mounted this way the bearings would
> be a small source of error in the torque signal, but I do not think it would
> be enough to worry about.
>
> Andre' B.
>
What it boils down to is one of the motors will have to be soft mounted
in a way that allows enough movment for the lever arm. strain gages to
measure the forces reacted from the case of the load device.
The drive shaft has U-joints in it. So no solid shaft on the input
side. The 9 incher doesn't have a assory shaft. The 8 incher does have
the 3/4 keyed shaft on the brush end. Good, but not good enough for 500
lbs of twist.
The mounting plate for the absorber must beable to rotate about 25 Deg,
freely and still support a 200 plus lbs motor while 500 to 1000 lbs of
torque is being transmitted into it.
--
Rich Rudman
Manzanita Micro
www.manzanitamicro.com
1-360-297-7383,Cell 1-360-620-6266
--- End Message ---
--- Begin Message ---
I had an adult that contacted me that is seeking an
Electric scooter (zappy type), that is powerful enough
to haul their 230 lbs around, yet light and foldable
for travel.
I am thinking at least a 200 watt motor and at least
one agm battery to go at least 10 mph and for 10 miles.
Please email me direct with your ideas or comments.
Thank you :-)
=====
' ____
~/__|o\__
'@----- @'---(=
. http://geocities.com/brucedp/
. EV List Editor & RE newswires
. (originator of the above ASCII art)
=====
__________________________________
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Yahoo! Finance: Get your refund fast by filing online.
http://taxes.yahoo.com/filing.html
--- End Message ---
--- Begin Message ---
Roland Wiench wrote:
>
> Hello Rich,
>
> There is a engineering calculation as:
>
> 1 ftlb per sec = 1.356 watts
> (meaning 1 ftlb at 60 RPM takes 1.356 watts of energy)
Shame on you to call it Engineering calculation :-)
The "1.356 watts of energy" statement makes no sense.
If you mean power, say it, else you may confuse newbies.
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
A slightly offbeat suggestion: An Exkate powerboard.
http://www.exkate.com
Pros:
It does 22mph, seems to last forever (claim is 10-12 miles), has regenerative
braking that can bring you to almost a complete stop, hauls my 225lbs around
with ease, and after making a bloody fool of myself hogging Bruce Meland's at
Woodburn 2002 for basically the whole weekend, it has earned its place among
those Things I Really, Really Want. It's actually a LOT easier to ride than a
real skateboard, due to very tight control of acceleration and braking. As an
accomplished non-skater, I picked it up in about 10 minutes.
Cons:
Unspeakably, breathtakingly expensive -- $1200+.
Not so bad compared to a Segway, though -- which it completely outperforms, and
though it's a bit heavy, you can carry it when you're not riding it -- it's a
skateboard after all.
--c.r.
Quoting Bruce EVangel Parmenter <[EMAIL PROTECTED]>:
> I had an adult that contacted me that is seeking an
> Electric scooter (zappy type), that is powerful enough
> to haul their 230 lbs around, yet light and foldable
> for travel.
>
> I am thinking at least a 200 watt motor and at least
> one agm battery to go at least 10 mph and for 10 miles.
>
> Please email me direct with your ideas or comments.
>
> Thank you :-)
>
>
>
>
>
> =====
> ' ____
> ~/__|o\__
> '@----- @'---(=
> . http://geocities.com/brucedp/
> . EV List Editor & RE newswires
> . (originator of the above ASCII art)
> =====
>
> __________________________________
> Do you Yahoo!?
> Yahoo! Finance: Get your refund fast by filing online.
> http://taxes.yahoo.com/filing.html
>
>
--- End Message ---
--- Begin Message ---
http://www.electronicsoutletmall.com/saveontronics/especiales.html
Probably a bunch of cheap chinese stuff, but let's
face reality, almost everything else comes from
China or India.
They have pretty good prices though.
Rod
--- Christopher Robison <[EMAIL PROTECTED]>
wrote:
> A slightly offbeat suggestion: An Exkate powerboard.
>
>
> http://www.exkate.com
>
> Pros:
> It does 22mph, seems to last forever (claim is 10-12
> miles), has regenerative
> braking that can bring you to almost a complete
> stop, hauls my 225lbs around
> with ease, and after making a bloody fool of myself
> hogging Bruce Meland's at
> Woodburn 2002 for basically the whole weekend, it
> has earned its place among
> those Things I Really, Really Want. It's actually a
> LOT easier to ride than a
> real skateboard, due to very tight control of
> acceleration and braking. As an
> accomplished non-skater, I picked it up in about 10
> minutes.
>
> Cons:
> Unspeakably, breathtakingly expensive -- $1200+.
>
>
> Not so bad compared to a Segway, though -- which it
> completely outperforms, and
> though it's a bit heavy, you can carry it when
> you're not riding it -- it's a
> skateboard after all.
>
>
>
> --c.r.
>
>
>
>
> Quoting Bruce EVangel Parmenter <[EMAIL PROTECTED]>:
>
> > I had an adult that contacted me that is seeking
> an
> > Electric scooter (zappy type), that is powerful
> enough
> > to haul their 230 lbs around, yet light and
> foldable
> > for travel.
> >
> > I am thinking at least a 200 watt motor and at
> least
> > one agm battery to go at least 10 mph and for 10
> miles.
> >
> > Please email me direct with your ideas or
> comments.
> >
> > Thank you :-)
> >
> >
> >
> >
> >
> > =====
> > ' ____
> > ~/__|o\__
> > '@----- @'---(=
> > . http://geocities.com/brucedp/
> > . EV List Editor & RE newswires
> > . (originator of the above ASCII art)
> > =====
> >
> > __________________________________
> > Do you Yahoo!?
> > Yahoo! Finance: Get your refund fast by filing
> online.
> > http://taxes.yahoo.com/filing.html
> >
> >
>
--- End Message ---
--- Begin Message ---
Much has happened lately, with the back and forth between
seeking employment, in training, and yet still unsure if
I was going to be hired.
The company I was applying to was within walking distance
of prearranged EV charging. So it was fairly easy to plan
that day. While my range is good enough to have me turn
around and head home if I had to, I would rather not
push my batteries and not be able to do anything else
that that day. It is just so easy to use the time while
the gain the miles back while the EV sits doing otherwise
nothing.
One my training sessions was to be in Cupertino. There
isn't any public charging in Cupertino. This company's
location is too far from what I had at hp Cupertino.
Cupertino is uphill from highway 101, and in between
Highway 280 and the mountain-side of Saratoga. It takes
more energy to get up there, but you recoup that on the
way back. Cupertino is just beyond my half way point, so
a charge would be needed.
This is where is pays to be an EAA member. I was able to
tap into the internal network of other EV drivers. There
was an EAA member a couple of blocks from the Symantec
World Headquarters off Stevens Creek Blvd.
He let me show up a half hour early before he left for his
work. I plugged into the 120VAC extension cord he draped
out from his garage.
I set the PFC-50 way-down to a 10 amp charge current flow
as his long skinny cord would not handle much more than
that (its not nice to burn up the cord that feeds you).
After I said my good-byes, I walked the side walks to my
training in the cold morning air. I would be in training
for 8 hours which is more than enough to regain the
amp-hours used. I should come back to a fully charged pack.
That's if nothing happens to interrupt the power (ie:
popped breaker, an oops I unplugged you, and other things
that can happen at non public charging).
I arrived on time, and spent the day learning what it was
to be a 'security person'. The day-light was almost gone
as I left at the end of the day.
The walk back to my EV, took me by the Cupertino city
hall. Their RAV4 EV was parked in their lot and plugged
into 'their' charger (not a public charging spot).
The cord on the gen2 spi charger was twisted and gnarled as
if the driver plugged the paddle in without a care of the
damage they did to the EV or its charger.
Next to the spi there were two tall sign poles with a
cement pad in-between. The pad had four rusty threaded studs
standing up out of the cement, as if to say, "a charger was
once here". The two poles also exclaimed 'We once marked
these two spots as Electric'. The city yanked their 2
ics-200 chargers, designed the coductive spots, and only
left the one spi.
After walking back, as I approached my EV, I could see the
PFC-50's bright blue LED was on solid. This means the PFC-50
had completed its charge cycle (done, complete, ready to go!).
It was an easy ride to Highway 101, where I spent the next
hour dancing in traffic to only go a few miles.
...
The next day, I was going to be training at a different site.
This one was in Redwood City. I would be trained for a
postion where they had yanked the current person working
there.
If all went well with my training, I would be assigned at
that site. The distance to work would be so short that it
would ruin an ICE, but be perfect for an EV.
...
I received a check in the mail from the company I have
been courting, so I can now say, "I am employed", again. I
am quite pleased to be part of the work force again. Good
thing, my rent just went up.
The prayers have been answered, and I thank all those that
did. But for a person employed as a Security Officer, I am
insecure that I could be yanked as easily as the person I
replaced :-o
=====
' ____
~/__|o\__
'@----- @'---(=
. http://geocities.com/brucedp/
. EV List Editor & RE newswires
. (originator of the above ASCII art)
=====
__________________________________
Do you Yahoo!?
Yahoo! Finance: Get your refund fast by filing online.
http://taxes.yahoo.com/filing.html
--- End Message ---
--- Begin Message ---
You are right, I should have said power. I look up this unit and conversion
factor up, and it is listed under the table of POWERS.
Roland
----- Original Message -----
From: "Victor Tikhonov" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Tuesday, February 17, 2004 3:22 PM
Subject: Re: Carbon pile? and blowers
> Roland Wiench wrote:
> >
> > Hello Rich,
> >
> > There is a engineering calculation as:
> >
> > 1 ftlb per sec = 1.356 watts
> > (meaning 1 ftlb at 60 RPM takes 1.356 watts of energy)
>
> Shame on you to call it Engineering calculation :-)
>
> The "1.356 watts of energy" statement makes no sense.
> If you mean power, say it, else you may confuse newbies.
>
> --
> Victor
> '91 ACRX - something different
>
>
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I just listed some stuff that may be of interest
for small EV projects like scooters.
Item 2597246121
http://cgi.ebay.com/ws/eBayISAPI.dll?
ViewItem&item=2597246121&category=42920&sspagename=STRK%3AMESSE%3AIT&rd=1
Item 2597246829
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2597246829&category=42920&sspagename=STRK%3AMESSE%3AIT&rd=1
Item 2596774807
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2596774807&category=42920&sspagename=STRK%3AMESSE%3AIT&rd=1
Item 2596775294
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2596775294&category=42920&sspagename=STRK%3AMESSE%3AIT&rd=1
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--- Begin Message ---
I've listed these on the list because I think
members can get a great deal on motors/controls
for their projects.
I also need money for an Alltrax control for
my GE Elec Trak riding mower,
"
Our new controller is called the
DCX-300ET
or DCX-400ET. DCX means it's for a seperately excited
or shunt motor.
The
300 & 400 is the current rating of the controller. A
500 amp version
will
also be available. The ET extension means it's built
specifically for
the
GE Elec-Trak (and WheelHorse) shunt wound motors.
The complete spec sheet for the 300 and 400 amp
controllers should be
on our
web site, www.alltraxinc.com , sometime this week.
"
Item 2597253525
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2597253525
Item 2597246829
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2597246829&category=42920&sspagename=STRK%3AMESSE%3AIT&rd=1
--- Rod Hower <[EMAIL PROTECTED]> wrote:
> I just listed some stuff that may be of interest
> for small EV projects like scooters.
>
> Item 2597246121
> http://cgi.ebay.com/ws/eBayISAPI.dll?
>
ViewItem&item=2597246121&category=42920&sspagename=STRK%3AMESSE%3AIT&rd=1
>
> Item 2597246829
>
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2597246829&category=42920&sspagename=STRK%3AMESSE%3AIT&rd=1
>
> Item 2596774807
>
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2596774807&category=42920&sspagename=STRK%3AMESSE%3AIT&rd=1
>
> Item 2596775294
>
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2596775294&category=42920&sspagename=STRK%3AMESSE%3AIT&rd=1
>
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--- Begin Message ---
Riches question:
> Anybody know of nifty ways to measure the torque on a shaft without
> using strain gages on the motor mounting base? There are some nifty
> systems that transmit the torque data wireless to a nearby sensor, So
> you don't have to touch the saft or motor, and you still get good data.
> I am looking for a complete system, not some engineering required, I
> have enough to build and design!
Using only hardware you have and understand is your goal. Torque
measurement is very desirable if only to check your data accuracy. But
you can do without.
In response to Roland Wiench:
"The whole purpose of this effort is to show how brush timing effect DC
motors used in the far end of drag racing. And put some numbers on a lot
of folks pre held notions."
The regular low stress road car should have advance too; this is
worthwhile to all of us.
Lee Hart writes:
"Rich, there's another approach you could take. Get TWO of the same
motors, and couple them up. Run one as a motor and the other as a
generator."
"Calibrate them (at zero advance), so you know their characteristics."
"Once you know their curves, you can change the driving motor, and
measure the results with the 'control' generator."
Using the same motor configuration for the calibration and test saves
a step in the test series. This method presumes that the losses are
only current related, but the actual power loss in the two units has
a small Volts contribution due to 'core power loss' I think. This is
very small, less (<<) than 1/2 %. Relative performance should be error
free.
"There is an even trickier trick; one that I've used for small motors and
would like to play with sometime with larger motors. Basically, you set
up a controller to rapidly switch the machine between motor and
generator action. No load on the shaft at all -- just a tachometer! It
depends on the symmetrical relationship between motor and generator
operation."
That would be fun, but the advance issue would cut down the range of
test on the generator pulsing.
This thread got a bit confusing without my seeing the existing 'dyno'
setup. It looks like a generator load from the following:
Rich Rudman wrote:
> But most of my power will recirculate back into the Batteries.
From: Seth <[EMAIL PROTECTED]>
"A gimbal mounted motor with a known lever arm and a load cell/ fish
scale or similar device is pretty good. Non contact torques sensors
like those from Himmelstein are not inexpensive. Like >$500 for a
calibration, plus shipping truck freight. So you can imagine what the
sensor costs. A strain gauge setup can be $150 for the gauge."
Himmelsteins are very good until they go out of calibration. Not worth
the money. Note that relative performance test-to-test is most
important with actual absolute numbers very desirable.
Rich again:
> I DID get to it all bolted down and put together yesterday. And
> actually Got to load down a motor.
So, you drive the motor from a pack and load the generator with a load
bank. All the juice you use is lost to heat. At least some of your
testing can be done with all the current going through the motor and
generator in series. The power supply then only provides the loss of
the two machines and you know the current is the same in both. Also,
the zero advance condition then provides the initial generator
calibration by methods mentioned below. The small delta V of the power
supply is a more accurate measure of loss than
((motor power)-(generator power)) / 2.
The most accurate measure of the effects of advance will be by
measuring loss delta V at the range of conditions (speeds). After the
series delta V test, delta I{motor} test sweeps are required (again
measured separately. delta I = I{motor} - I{gen}. The delta V test
alone doesn't allow a range of torque vs. speed at different currents.
Before any testing, the motor and generator (hopefully the same actual
hardware parts) should be run with no load to establish loss at zero
output torque-power. To simplify analysis, most testing should be done
with no motor driven fans (if you actually want to know the motor
performance). A separate, off board fan should cool both units.
> 12 volts is boring.... Adjustable
> brushes with some real world loading is rather eye opening. I can
> adjust the power consumed by over %500 with just brush movment.
eye opening should not equal boring
From: Doug Weathers <[EMAIL PROTECTED]>
Rich Rudman wrote:
> Anybody know of nifty ways to measure the torque on a shaft without
"I suppose you could attach a heavy flywheel to the motor shaft and
measure how long it takes to get it spun up to a particular RPM. In
this case the force that resists the twist is the inertia of the
flywheel, which depends on its mass and radius."
"I understand that a series-wound DC motor produces maximum torque at
zero RPMs, which means that as RPM increases, the torque falls off."
To the first approximation, the torque is constant with constant Amps
from 0 rpm.
"The lever-and-scale system would always be measuring torque at the zero
RPM point."
You misunderstand; the reaction of the casing-field is what is
measured. The casing is free to rotate.
"If you want to know the torque at different RPMs, the flywheel can tell
you. In fact, given the curve of RPM vs. time, a little calculus
should tell you the torque at every RPM value."
Some diesel engines with an EEC will do an automatic power check this
way.
> I am looking for a complete system, not some engineering required, I
> have enough to build and design!
"Given an RPM sensor (which you will already have), a flywheel of known
weight and diameter, a computer, and a certain amount of math, you
should be able to derive torque information without much extra
engineering."
This is a bigger mechanical problem than the two motor idea. Worthy of
consideration though and a closer simulation of race conditions. The
effects of advance would require high data rates though.
From: Rich Rudman <[EMAIL PROTECTED]>
"Lee's twin motor concept is what I am doing. Nice for playing around.
I do want to measure the real torque. Strain gages or torque shaft
windup is where I am going."
With a long shaft and bump on each end, a 'time shift' / cycle gives a
torque indication and can be calibrated geometrically. But, real
torque is a bit of an expensive luxury.
______________________________________________________________________
--- End Message ---
--- Begin Message ---
> Anybody know of nifty ways to measure the torque on a shaft without
> using strain gages on the motor mounting base?
Check this out for a project that you can build, and has been done before
http://www.circuitcellar.com/flash2002/second.htm
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Sunday, February 15, 2004 4:26 PM
Subject: Re: Cheap magnachargers on eBay
SNIP
> fuse
> DC rated!
> ___ ___ ___ 600v bridge _______/\ _____+
> AC _____|_/_|__|_/_|__|_/_|______ rectifier _|_ _|_ \/ |
> hot | | | | |___| _| /_\ /_\ |
> | | | | timer || |_ /____ ______| | |
> | | | | || |_ \ _| || |_ | | volt- / \
> | | | | || |_ _| || |_ | | meter \_/
> AC _____|_/_|__|_/_|_____________|_____| || |_____ | ___| |
> neutral |___| |___| variac isolation _|_ _|_ |
> GFCI circuit transformer /_\ /_\ _ |
> breaker 120/240vac in |____|___/ \__|__-
> 480vac out \_/
> ammeter
>
I was taught to not put any kind of switch in the neutral line. Has
something changed?
David, has worked with electricity a long time, but still learning (or at
least trying:-)
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--- Begin Message ---
With the new schedule for this years Tour de Sol up at
http://www.nesea.org/transportation/tour/
it appears to be very BEV-friendly as it stays in a compact area, rather
than "tour"ing large distances. The posted schedule starts in
Burlington, NJ for 3 days with various tests in the area. The forth day
is 15 miles down the road for a display in Trenton NJ. The fifth day is
~70 miles away in New York City (and depending where stop overnight
could break that 70 miles in half?).
So in my case the 300 miles to get there becomes the major challenge :-)
_________
Jim Coate
1970's Elec-Trak
1992 Chevy S-10 BEV
1997 Chevy S-10 NGV
http://www.eeevee.com
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--- Begin Message ---
Recharge? I was talking about discharge. Like the goofy internal
resistance that seems to be associated with lithium. Remember Victor's
90Ah thundersky pack that would do like 90A before hitting the low
voltage limit at 2.5V? Or maybe it was even less current than that. I
don't remember. Victor is working on a
super/mega/wicked/gnarly-capacitor bank for power in parallel, last I
heard.
Seth
On Feb 17, 2004, at 11:57 AM, Jim Coate wrote:
Seth wrote:
... And IMO, lithium is still a self powered power resistor unless
you are talking cell phones and laptops.
Care to elaborate on that? I knew the advanced chemistries were less
efficient on recharge then lead acid, but is Lithium that much worse
then say NiMH?
- Jim
aka "I won but still lost on eBay"
_________
Jim Coate
1970's Elec-Trak
1992 Chevy S-10 BEV
1997 Chevy S-10 NGV
http://www.eeevee.com
--- End Message ---
--- Begin Message ---
Otmar wrote:
>
> > > Anybody know of nifty ways to measure the torque on a shaft without
> > > using strain gages on the motor mounting base?
>
> Check this out for a project that you can build, and has been done before
>
> http://www.circuitcellar.com/flash2002/second.htm
>
> --
> -Otmar-
>
> http://www.CafeElectric.com/ Home of the Zilla.
> http://www.evcl.com/914 My electric 914
Nice !!!
Where can I buy one??
And for how much. I am using a drive shaft.
Sorry for being a bit behind the 8 ball today on the Dyno stuff, doing
real work on green boxes.
One got hooked to chassis to Batt neg while running.... Long story. It
just went back into it's case, and now onto the last Box of this Sheet
metal run. Then by Friday, a batch of 50 new cases!!! And then I am out
of Heatsinks...... Groan....
Dyno will be twin motors, and Strain gages, and a lever arm.
I am going to have to step through Martin's post, there a few points
that are not quite as clear cut as is implied.
I want to have a charger living before I quit this evening, Back to the
Green boxes... and solder smoke.
--
Rich Rudman
Manzanita Micro
www.manzanitamicro.com
1-360-297-7383,Cell 1-360-620-6266
--- End Message ---
--- Begin Message ---
David McAlister wrote:
> I was taught to not put any kind of switch in the neutral line. Has
> something changed?
That is is generally correct; you don't switch just the neutral line.
But in this case, the 2nd pole of the circuit breaker and GFC are
*simultaneously* breaking both the hot and neutral. This is perfectly
ok, and frequently done to add to the contact voltage rating, provide
redundancy, or allow its use for 240v (which has two hot leads).
--
"Never doubt that a small group of committed people can change the
world. Indeed, it's the only thing that ever has!" -- Margaret Meade
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Hi Bruce,
I weigh about 250 and have a scooter with a 600 watt 24 vdc motor. It's a
really nice scooter and it's OK on the flat, but it's not quite enough on
any hills. I would suggest something with at least an 800 watt 36 vdc motor.
Here is a couple I found on eBay that look almost exactly like mine, but
with the bigger motor.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3661033376&category=47350
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3660005753&category=22703
I've also seen one that looks the same, but is 1000 watts.
I would stay away from the ones with the sleek plastic bodies. I bought some
for the kids and the bodies didn't last a month. Also the electronics failed
on one of them in the first couple of days.
Later,
Dan
----- Original Message -----
From: "Bruce EVangel Parmenter" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>
Sent: Tuesday, February 17, 2004 2:08 PM
Subject: seeking: an escoot that can fold for travel
> I had an adult that contacted me that is seeking an
> Electric scooter (zappy type), that is powerful enough
> to haul their 230 lbs around, yet light and foldable
> for travel.
>
> I am thinking at least a 200 watt motor and at least
> one agm battery to go at least 10 mph and for 10 miles.
>
> Please email me direct with your ideas or comments.
>
> Thank you :-)
>
>
>
>
>
> =====
> ' ____
> ~/__|o\__
> '@----- @'---(=
> . http://geocities.com/brucedp/
> . EV List Editor & RE newswires
> . (originator of the above ASCII art)
> =====
>
> __________________________________
> Do you Yahoo!?
> Yahoo! Finance: Get your refund fast by filing online.
> http://taxes.yahoo.com/filing.html
>
--- End Message ---
