EV Digest 5571
Topics covered in this issue include:
1) Re: voltage limit 144 (and Field Weakening...)
by [EMAIL PROTECTED]
2) Re: Field Weakening
by [EMAIL PROTECTED]
3) RE: Regen - as a 'brake'
by "Michaela Merz" <[EMAIL PROTECTED]>
4) No load DC motor behavior
by "Seth Myers" <[EMAIL PROTECTED]>
5) boo to smithsonian
by "Peri Hartman" <[EMAIL PROTECTED]>
6) Re: The PROPER - and inexpensive - DC/DC Converter
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
7) Re: The PROPER - and inexpensive - DC/DC Converter
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
8) Smithsonian anti EV?
by Dave Cover <[EMAIL PROTECTED]>
9) Re: boo to smithsonian
by "Andre' Blanchard" <[EMAIL PROTECTED]>
10) RE: Regen - as a 'brake'
by "Roger Stockton" <[EMAIL PROTECTED]>
11) Re: Is the Ranger conversion by a listee?
by "Bob Rice" <[EMAIL PROTECTED]>
12) Re: boo to smithsonian
by "Roderick Wilde" <[EMAIL PROTECTED]>
13) re: ACkwhr meter
by [EMAIL PROTECTED]
14) Circuit breaker question
by Dave Cover <[EMAIL PROTECTED]>
15) RE: Circuit breaker question
by "Roger Stockton" <[EMAIL PROTECTED]>
16) Re: boo to smithsonian
by "Roderick Wilde" <[EMAIL PROTECTED]>
17) RE: Circuit breaker question
by "Rick Todd" <[EMAIL PROTECTED]>
18) Reluctance Motor Drive
by "Mark E. Hanson" <[EMAIL PROTECTED]>
19) RE: Circuit breaker question
by Dave Cover <[EMAIL PROTECTED]>
20) Re: one for the Sinclair C5 owners...
by "Peter VanDerWal" <[EMAIL PROTECTED]>
21) Re: The PROPER - and inexpensive - DC/DC Converter
by "Peter VanDerWal" <[EMAIL PROTECTED]>
22) Re: No load DC motor behavior
by Lee Hart <[EMAIL PROTECTED]>
23) RE: Circuit breaker question
by "Roger Stockton" <[EMAIL PROTECTED]>
24) RE: Circuit breaker question
by "Rick Todd" <[EMAIL PROTECTED]>
25) Re: boo to smithsonian
by "Michael" <[EMAIL PROTECTED]>
26) Re: Reluctance Motor Drive
by Lee Hart <[EMAIL PROTECTED]>
27) Re: one for the Sinclair C5 owners...
by Lee Hart <[EMAIL PROTECTED]>
--- Begin Message ---
The field weakening thing reminds me of a time when I was helping my brother
tune his Z28 for bracket drag racing. We did not have any fancy tools, test
equipment, dyno, or such, but, we had lots of back country roads. We wanted to
tune the carburetor secondaries at wide open throttle under real load
conditions. To do this, being the smaller of stature, I laid on top of the
engine. My brother tied down the hood with my feet sticking out the front.
Away we went in full drag mode. I then proceeded to adjust the carburetor.
Quite and experience with your face about three inches over the throat of a
750CFM at WOT spread bore! Hot and loud. We certainly got the attention of
some boys fishing over the edge of a bridge. I guess it was a sight – Z28 with
open headers ripping past at about 100 mph with a pair of feet sticking out
from under the hood!
The next day, at the races, not only did we break out, we were disqualified
because the ET was so far out we were accused of having engine mods outside our
class. I guess we were not that good at the dialing thing. Very disappointed
about the track thing but very pleased with the cars performance.
Anyway, I’m guessing that may be a way to fine tune the field weakening. Have
someone under the hood so they can observe the brushes while adding weakening
bypass current maybe 10% at a time. I guess that’s a Burt Munro style, but, if
it works…
Ken
-----Original Message-----
From: Rich Rudman <[EMAIL PROTECTED]>
To: ev@listproc.sjsu.edu
Sent: Thu, 15 Jun 2006 08:35:17 -0700
Subject: Re: voltage limit 144
The Warp and the AvDc are basicly the same motor. Buildt by differnt folks.
The Warp give you a little better cost benifit ratio.
John Wayland won't be using Field weakening again this year.. too much brush
carnage.Messing with field strengths is a carefull adjustment and test
thing.
Not blast it to bits and then sweep up the peices.
Maybe at 28 to 48 volts but not at 360 and 2000 amps.
The motors are wound for the 48 volt for lower voltages, The high voltage
motors seam to be the same build from 96 volts and up. We have seen the
exact same motor badged from 96 to 156.
So.. What changes??? We don't know. The have the same case, Comm and field
turns. Pretty much the same motor then.
Rich Rudman
Manzanita Micro
----- Original Message -----
From: "Tim Humphrey" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Wednesday, June 14, 2006 1:03 PM
Subject: RE: voltage limit 144
>
> >
> >
> > -----Original Message-----
> > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
> > Behalf Of Rich Rudman
>
> >
> > The 9 incher doesn't get into trouble until you can find 170 volts on
the
> > motor and over 1000 amps.
> >
> > The Raptors were tested with a AVDC 8 inch motor and 156 volts.
> >
> > So.. 156 is one of thier sweat spots.
> >
> > Rich Rudman
> > Manzanita Micro
> >
>
>
> This raises a question in my mind....
>
> I would assume that the 170v limit is a result of the way the motor is
built and timed. It speculate that it is a
> function of the inductive properties and relationships of the armature and
field coils.
>
> OK, so, we've determined that an ADC 9 incher, timed at 10 deg before, can
withstand 170v and 1000a.
>
> Doesn't it stand to reason that John's field weakening scheme will screw
with these values. If he weakens the field,
> will it set the maxV and maxA higher or lower. I'm guessing with a
weakened field he can raise the MaxV.
>
> Will a motor wound for 48v cont behave the same as one wound for 96v cont,
if they are both 9" ADC motors?? I would
> assume the maxV and maxA would be different in this case. Are the Warp 9's
close enough to the ADC 9's that the same
> values apply?
>
>
> Stay charged!
> Hump
>
>
>
________________________________________________________________________
Check out AOL.com today. Breaking news, video search, pictures, email and IM.
All on demand. Always Free.
--- End Message ---
--- Begin Message ---
In a message dated 6/15/06 2:17:10 PM Pacific Daylight Time,
[EMAIL PROTECTED] writes:
<< Subj: Field Weakening
Date: 6/15/06 2:17:10 PM Pacific Daylight Time
From: [EMAIL PROTECTED] (Rush)
Sender: [EMAIL PROTECTED]
Reply-to: ev@listproc.sjsu.edu
To: ev@listproc.sjsu.edu
When Dennis was showing us his CurrentEliminator features, one of them was
the field weakening on his motor. You could see part of it, most of it was
under a cowling that protected the motor. It looked pretty simple, just some
bands
across 2 of the motor terminals. His comm was bright and clean so there was
no arcing from the weakening and he has been using it for years.
And since RIch posted the comment about field weakening, I was wondering how
it is achieved. I've done a little web research and found a picture at
http://www.railway-technical.com/field.gif
Is the shunt switch necessary? How does one go about figuring the
resistance? From what I could see on the CE it looked like it was just a wide
band of
metal (copper?) that snaked back and forth a couple times between the motor
terminals.
There is also a patent http://www.freepatentsonline.com/4378517.pdf, that
incorporates field weakening, amount other things. The patent states - "The
field weakening circuit comprises a transistor in series with a resistor. The
base
of the transistor receives a series of pulses such that the transistor is
alternately switched fully on land fully off. the mean impedance of the filed
weakening circuit defined by the transistor and resistor can be controlled down
to a minimum defined by the resistance of resistor by controlling the
mark/space ration of the pulses applied to the base of the transistor" - it
seams
pretty simple...
Has anybody done any experimentation with a 9" ADC motor? Taking Dennis's CE
as an example, once the 'formula' is found it seems as if there is basically
no upkeep on it.
Thanks for the input,
Rush >>
Hi Rush, Next time you get to see the CE I will unwrap it and explain how
field weaking works on it.The wraps you saw are nicrome and only 1 side hooks
directly to a field terminal.There are multiple taps off that nicrome wrap to a
switching network.Rich seems to think field weaking works at a low rpm as well
as hi rpm,but on the CE I use it at high rpms and never bypass more than half
the resistance of the fields.Also the CE must be on a well preped track or she
could end up sideways when FW is applied.As far as arcing the brushes,I do
not have any arc tracers coming off my brushes in FW just a white line on the
trailing edge.Any more arcing would cause brush damage and comm.pitting that
could compound next time out. Dennis Berube
--- End Message ---
--- Begin Message ---
Roger Stockton wrote:
> Sorry, it has taken me a while to dredge up the name of a potential
> alternator solution from the depths of my memory. I knew I'd come
> across something suitable before, but couldn't remember the name to
> search it up. Check out:
>
> <http://www.fabcopower.com/generat/bgen.htm>
Thanks Roger. I have contacted the company. Let's see what they say.
Michaela
--- End Message ---
--- Begin Message ---
I'm a newbie, but have reasearched a bit and know some Sparrow owners.
I am considering a traditional ev conversion, with clutch, existing (manual)
gearset, etc.
The question I have is about the noted behavior of dc motors while under no
load conditions, i.e. if you are out of gear/clutch is depressed, and you hit
the gas:
DC motors under no load are supposed to take off or go out of control. Is this,
in practical experience, a problem, or, can it be idiot-proofed somehow so this
never happens (aside from just driving intelligently, of course)?
Curtis "C" series controllers operate at a reduced 1.5 kHz switching
frequency up
to 10% of throttle demand - preventing jerky starts, etc. Does this help with
the no load DC motor behavior situation at all?
Thanks,
Seth Myers
(in the style of L. Hart:)
"This life's dim windows of the soul,
distort the world from pole to pole,
and causes one to believe a lie,
when one sees with, and not through, the eye"
- William Blake
(found it from material from www.rzim.org, got to quote it for my vision system
thesis)
- 99 diesel Beetle running on B20 (oops, wrong list!), may try to make my own
with
www.localb100.com as otherwise I have to drive 30 miles just to find a bio (and
only B20) pump
--- End Message ---
--- Begin Message ---
fyi - Peri Hartman
http://seattlepi.nwsource.com/national/1155AP_Electric_Car_Booted.html
Friday, June 16, 2006 · Last updated 6:49 a.m. PT
Smithsonian removes electric-car exhibit
THE ASSOCIATED PRESS
(photo omitted)
General Motors Corp. will initially lease, but not sell the EV1, the
company's electric car, shown in this undated handout file photo, company
officials said Tuesday, Aug. 27, 1996. (AP Photo/HO)
WASHINGTON -- Just weeks before the release of a movie about the death of
the electric car from the 1990s, the Smithsonian Institution has removed its
EV1 electric sedan from display.
The National Museum of American History removed the rare exhibit yesterday,
just as interest in electric and hybrid vehicles is on the rise. The
upcoming film "Who Killed the Electric Car?" questions why General Motors
created the battery-powered vehicles and then crushed the program a few
years later. The film opens June 30th.
GM happens to be one of the Smithsonian's biggest contributors. But museum
and GM officials say that had nothing to do with the removal of the EV1 from
display. A museum spokeswoman says the museum simply needed the space to
display another vehicle, a high-tech SUV.
The Smithsonian has no plans to bring the electric car back on view. It will
remain in a Suitland storage facility.
--- End Message ---
--- Begin Message ---
Excess Solutions in Milpitas CA has in the past had 35 watt dc/dc converters
in the 48 to 12v range. I have used one with a 36 to 72v input and 12v out
at 35watts. . Price 3 to 5 dollars. Looks like this is what you need.
Just enough to keep the 12v battery topped off. I've used these two at a
time. One for the head light and one for the rest of the 12v
systems(running lights/contactor) no 12v battery used....
http://www.excesssolutions.com/cgi-bin/category/0
Lawrence Rhodes......
----- Original Message -----
From: "Steven Lough" <[EMAIL PROTECTED]>
To: "Electric Vehicle Discussion List RCVR" <ev@listproc.sjsu.edu>;
<[EMAIL PROTECTED]>
Sent: Thursday, June 15, 2006 5:46 PM
Subject: The PROPER - and inexpensive - DC/DC Converter
> I HAVE the EV-Grin.... Enjoying my 48 volt ( X - 125cc Yamaha Scooter)
>
> 4 Hawkers... Now I am working out the 12v. system. Have a small Gell
> battery as a float. Total LOAD lights, signals Horn, Brake Lites, main
> contactor coil, is less than 11 amps.
>
> Looking at this TYCO.. Model EUE200/120 works out to about 16amps.
> Specs at:
>
http://www.power.tycoelectronics.com/BinaryGet.aspx?ID=9734645d-e42e-4139-ae3e-b64bd7648040
>
> But the question IS: is there a better DC/DC, or less expensive, with
> an output round 12 to 15 amps ? ? ?
>
> Again.... Basic NEEDS 48VDC input, 12VDC output, 11-15Amps
> --
> Steven S. Lough, Pres.
> Seattle EV Association
> 6021 32nd Ave. N.E.
> Seattle, WA 98115-7230
> Day: 206 850-8535
> Eve: 206 524-1351
> e-mail: [EMAIL PROTECTED]
> web: http://www.seattleeva.org
>
--- End Message ---
--- Begin Message ---
http://www.excesssolutions.com/cgi-bin/item/ES3932 Here is a simple 1 amp
dc/dc. Works up to 72vdc. I used a 48vdc contactor to eliminate that drain
on the DC/DC. LR.......
----- Original Message -----
From: "Steven Lough" <[EMAIL PROTECTED]>
To: "Electric Vehicle Discussion List RCVR" <ev@listproc.sjsu.edu>;
<[EMAIL PROTECTED]>
Sent: Thursday, June 15, 2006 5:46 PM
Subject: The PROPER - and inexpensive - DC/DC Converter
> I HAVE the EV-Grin.... Enjoying my 48 volt ( X - 125cc Yamaha Scooter)
>
> 4 Hawkers... Now I am working out the 12v. system. Have a small Gell
> battery as a float. Total LOAD lights, signals Horn, Brake Lites, main
> contactor coil, is less than 11 amps.
>
> Looking at this TYCO.. Model EUE200/120 works out to about 16amps.
> Specs at:
>
http://www.power.tycoelectronics.com/BinaryGet.aspx?ID=9734645d-e42e-4139-ae3e-b64bd7648040
>
> But the question IS: is there a better DC/DC, or less expensive, with
> an output round 12 to 15 amps ? ? ?
>
> Again.... Basic NEEDS 48VDC input, 12VDC output, 11-15Amps
> --
> Steven S. Lough, Pres.
> Seattle EV Association
> 6021 32nd Ave. N.E.
> Seattle, WA 98115-7230
> Day: 206 850-8535
> Eve: 206 524-1351
> e-mail: [EMAIL PROTECTED]
> web: http://www.seattleeva.org
>
--- End Message ---
--- Begin Message ---
I just read an article that said the Smithsonian Museum just removed it's EV1
from display. They
need the space for a "high tech SUV." Coincidentally, GM is one their largest
contributors.
I'm not sure if it will work, but here is a link to the story. You'll need to
past the whole link
in to your browser.
http://news.yahoo.com/s/ap/20060616/ap_on_go_ot/electric_car_booted;_ylt=An.zUYCBUbWA0OS0.U3NIeyyFz4D;_ylu=X3oDMTA0cDJlYmhvBHNlYwM-
Dave Cover
--- End Message ---
--- Begin Message ---
At 09:40 AM 6/16/2006, you wrote:
fyi - Peri Hartman
http://seattlepi.nwsource.com/national/1155AP_Electric_Car_Booted.html
Friday, June 16, 2006 · Last updated 6:49 a.m. PT
Smithsonian removes electric-car exhibit
THE ASSOCIATED PRESS
(photo omitted)
General Motors Corp. will initially lease, but not sell the EV1, the
company's electric car, shown in this undated handout file photo, company
officials said Tuesday, Aug. 27, 1996. (AP Photo/HO)
WASHINGTON -- Just weeks before the release of a movie about the death of
the electric car from the 1990s, the Smithsonian Institution has removed
its EV1 electric sedan from display.
The National Museum of American History removed the rare exhibit
yesterday, just as interest in electric and hybrid vehicles is on the
rise. The upcoming film "Who Killed the Electric Car?" questions why
General Motors created the battery-powered vehicles and then crushed the
program a few years later. The film opens June 30th.
GM happens to be one of the Smithsonian's biggest contributors. But museum
and GM officials say that had nothing to do with the removal of the EV1
from display. A museum spokeswoman says the museum simply needed the
space to display another vehicle, a high-tech SUV.
The Smithsonian has no plans to bring the electric car back on view. It
will remain in a Suitland storage facility.
Contact page.
http://americanhistory.si.edu/about/contactfaq.cfm
__________
Andre' B. Clear Lake, Wi.
--- End Message ---
--- Begin Message ---
Death to All Spammers wrote:
> Can you leave the charger as-is and adjust the alternator output like
> Victor does with his AC system (slide pot on the steering wheel)?
I don't believe this would work very well due to the wide input range of
the PFCxx chargers.
It should be relatively straightforward to connect a regen control pot
to the current control input of the PFCxx's remote control port, so you
could still control regen with a slide pot on the shifter or steering
wheel, etc. Does it really matter all that much what precisely the pot
controls as long as sliding it one way increases regen and the other way
decreases regen braking?
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Or better yet CT or Mass as it is in Worcester MA. Not exactly a hotbed of
EV activity, but we are working on that!
Good luck!
Bob.
----- Original Message -----
From: <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Friday, June 16, 2006 1:15 AM
Subject: Is the Ranger conversion by a listee?
> You don't get the batteries or racks, but it looks like a deal for anyone
in MD:
>
> http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=4651790535
>
--- End Message ---
--- Begin Message ---
Chris Paine just sent me this link to a much more in-depth article in The
Washington Post today titled: An Electric Car, Booted.
http://www.washingtonpost.com/wp-dyn/content/article/2006/06/15/AR2006061502052.html
Roderick Wilde
----- Original Message -----
From: "Andre' Blanchard" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Friday, June 16, 2006 8:29 AM
Subject: Re: boo to smithsonian
At 09:40 AM 6/16/2006, you wrote:
fyi - Peri Hartman
http://seattlepi.nwsource.com/national/1155AP_Electric_Car_Booted.html
Friday, June 16, 2006 · Last updated 6:49 a.m. PT
Smithsonian removes electric-car exhibit
THE ASSOCIATED PRESS
(photo omitted)
General Motors Corp. will initially lease, but not sell the EV1, the
company's electric car, shown in this undated handout file photo, company
officials said Tuesday, Aug. 27, 1996. (AP Photo/HO)
WASHINGTON -- Just weeks before the release of a movie about the death of
the electric car from the 1990s, the Smithsonian Institution has removed
its EV1 electric sedan from display.
The National Museum of American History removed the rare exhibit yesterday,
just as interest in electric and hybrid vehicles is on the rise. The
upcoming film "Who Killed the Electric Car?" questions why General Motors
created the battery-powered vehicles and then crushed the program a few
years later. The film opens June 30th.
GM happens to be one of the Smithsonian's biggest contributors. But museum
and GM officials say that had nothing to do with the removal of the EV1
from display. A museum spokeswoman says the museum simply needed the space
to display another vehicle, a high-tech SUV.
The Smithsonian has no plans to bring the electric car back on view. It
will remain in a Suitland storage facility.
Contact page.
http://americanhistory.si.edu/about/contactfaq.cfm
__________
Andre' B. Clear Lake, Wi.
--
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Version: 7.1.394 / Virus Database: 268.9.0/367 - Release Date: 6/16/2006
--- End Message ---
--- Begin Message ---
Yup, I am back to the house meter concept.
I wanted an onbard AC kwhr meter (small) so that I could measure my power
useage at work. However, if I have a separate one at home, I can figure my
charger efficiency and calculate based on emeter the AC power useage at
work.
I did get a response from a company who makes a small cheap one,
http://www.prodigit.com.tw/e2000m.htm
However, to make a unit that handles my needed 20 Amps (7 more amps), they
would be looking for an order of more than a few.
Any distributors on this list who want to distribute these?
Otherwise, I'll go with option 1, and wait a few more years for a
cheaper, higher current, small ACkwhr meter.
Ben
--- End Message ---
--- Begin Message ---
I need to clear up some of my confusion over circuit breakers. I'm hoping to
put a circuit breaker
in the middle of my pack. This will be in the back of the car and allow me to
split the pack when
I need to work on things. I'd prefer having a circuit breaker I can reset
instead of replacing
fuses. I will have a higher rated fuse near the controller as an additional
precaution.
I've seen a DC circuit breaker that is rated for sufficient amperage, but the
voltage rating is a
little low. It's rated for 125 volts DC, but can I still use it if the pack
voltage is double
that?
Also, if I can get a 3 pole breaker for a good price, does it matter if I'm
only using one of the
three poles? It has an AC and a DC rating, sufficient for the task. If I split
the single line to
run through all three poles, does that triple the current needed to trip the
breaker? Dumb
questions for some of you, but for me ....
Thanks
Dave Cover
--- End Message ---
--- Begin Message ---
Dave Cover wrote:
> Also, if I can get a 3 pole breaker for a good price, does it
> matter if I'm only using one of the three poles? It has an AC
> and a DC rating, sufficient for the task. If I split the
> single line to run through all three poles, does that triple
> the current needed to trip the breaker?
You need to get the specs/datasheet for your particular breaker.
Sometimes the DC voltage rating is based on having more than one pole of
the breaker wired in series, and sometimes there is a specific way that
the poles must be wired (e.g. the two outside poles are wired in series,
but the center pole is unused, etc.).
Wiring multiple poles in series typically multiplies the DC voltage
rating:
overall rating = number of poles in series
* DC voltage rating of each pole
If you wire multiple poles in parallel, it will likely increase the
current rating somewhat, but probably not triple for 3 poles, etc.
because the current will not divide equally between the poles and the
one carrying most of the current will trip first.
Hope this helps,
Roger.
--- End Message ---
--- Begin Message ---
Hi All, Please let The Smithsonian know how you feel. Here is their email
address, [EMAIL PROTECTED] I already wrote them but I can not say what I wrote on
this list. Suffice it to say that I was more than a little dismayed and
disappointed with the action they took.
Roderick Wilde
----- Original Message -----
From: "Peri Hartman" <[EMAIL PROTECTED]>
To: "evdl" <ev@listproc.sjsu.edu>
Sent: Friday, June 16, 2006 7:40 AM
Subject: boo to smithsonian
fyi - Peri Hartman
http://seattlepi.nwsource.com/national/1155AP_Electric_Car_Booted.html
Friday, June 16, 2006 · Last updated 6:49 a.m. PT
Smithsonian removes electric-car exhibit
THE ASSOCIATED PRESS
(photo omitted)
General Motors Corp. will initially lease, but not sell the EV1, the
company's electric car, shown in this undated handout file photo, company
officials said Tuesday, Aug. 27, 1996. (AP Photo/HO)
WASHINGTON -- Just weeks before the release of a movie about the death of
the electric car from the 1990s, the Smithsonian Institution has removed its
EV1 electric sedan from display.
The National Museum of American History removed the rare exhibit yesterday,
just as interest in electric and hybrid vehicles is on the rise. The
upcoming film "Who Killed the Electric Car?" questions why General Motors
created the battery-powered vehicles and then crushed the program a few
years later. The film opens June 30th.
GM happens to be one of the Smithsonian's biggest contributors. But museum
and GM officials say that had nothing to do with the removal of the EV1 from
display. A museum spokeswoman says the museum simply needed the space to
display another vehicle, a high-tech SUV.
The Smithsonian has no plans to bring the electric car back on view. It will
remain in a Suitland storage facility.
--
No virus found in this incoming message.
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Version: 7.1.394 / Virus Database: 268.9.0/367 - Release Date: 6/16/2006
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--- End Message ---
--- Begin Message ---
Dave,
What amperage did you need for your circuit breaker?
-Rick Todd
Peterson Electric Panel Mfg. Co.
Department of Engineering
5550 McDermott Dr.
Berkeley, IL 60163
Phone (708) 449-2270
Fax (708) 449-2269
Website www.petersonpanel.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Dave Cover
Sent: Friday, June 16, 2006 12:14 PM
To: ev@listproc.sjsu.edu
Subject: Circuit breaker question
I need to clear up some of my confusion over circuit breakers. I'm hoping to
put a circuit breaker in the middle of my pack. This will be in the back of
the car and allow me to split the pack when I need to work on things. I'd
prefer having a circuit breaker I can reset instead of replacing fuses. I
will have a higher rated fuse near the controller as an additional
precaution.
I've seen a DC circuit breaker that is rated for sufficient amperage, but
the voltage rating is a little low. It's rated for 125 volts DC, but can I
still use it if the pack voltage is double that?
Also, if I can get a 3 pole breaker for a good price, does it matter if I'm
only using one of the three poles? It has an AC and a DC rating, sufficient
for the task. If I split the single line to run through all three poles,
does that triple the current needed to trip the breaker? Dumb questions for
some of you, but for me ....
Thanks
Dave Cover
--- End Message ---
--- Begin Message ---
Hi,
I was curious why (in the textbooks & IR apps-notes) you always see a
2-switch fet drive with 2-diodes instead of a full H-bridge drive for a
reluctance motor drive. Looks like a 2-switch forward converter. Would you
get more power with a full bridge drive or would it cause other problems?
Thanks,
Mark
---------------------------------
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--- End Message ---
--- Begin Message ---
--- Rick Todd <[EMAIL PROTECTED]> wrote:
> Dave,
> What amperage did you need for your circuit breaker?
>
I have a Z1K and I plan on limiting the battery side amperage to 300 or so.
When I first get the
car on the road I will have 153 volts but will increase it to over 300 when I
get more racks
built. My pack is made up of the 1.2 volt NiCads with busbar interconnects and
2/0 cable to the
controller. Of course, I'll be playing by ear as I go along. I'm planning on
using the car as a
daily driver, but I want to make it as fun as possible. Range or fun? Range or
fun? Hmmmmmm
Now, taking an optimistic view of Rogers input, I could use a 250 amp, 125VDC 3
pole breaker wired
through all three legs to handle the 300 volt pack. But reality says I won't
know for sure without
testing. Once again, it's all a matter of money, and I'm trying to find an
affordable compromise
that won't burn up my car. Some day I'd like to try throwing money at a problem
to solve it.
Dave Cover
--- End Message ---
--- Begin Message ---
> I remember his computer. Unfortunately, I don't think the C5 was brought
> to
> the US, except in rare cases. This car has a lot of Nerd appeal... and I
> think it'd be perfect for Micro-car rallies.
Not a lot of them made it to the US, but a few did. I have one, and I've
heard about a couple others. Saw one on Ebay once, but it went for more
than I was willing to part with at the time (Besides, I don't really need
TWO of them)
Cheers, Pete.
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
--- End Message ---
--- Begin Message ---
> But the question IS: is there a better DC/DC, or less expensive, with
> an output round 12 to 15 amps ? ? ?
>
Hmm, www.electricmotorsport.com offers a 48V to 12V @ 10A DC/DC for $25.
It's designed for electric Scooters. Not quite the current you are
looking for, but perhaps you could use two of them?
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
--- End Message ---
--- Begin Message ---
Seth Myers wrote:
> behavior of dc motors while under no load conditions, i.e. if you are
> out of gear/clutch is depressed, and you hit the gas: DC motors under
> no load are supposed to take off or go out of control. Is this, in
> practical experience, a problem, or, can it be idiot-proofed somehow
> so this never happens (aside from just driving intelligently, of course)?
Yes; if a DC motor loses its field, its speed heads for "infinity", and
it can destroy itself from excessive rpm.
However, this is only a problem if you lose the field. PM (Permanent
Magnet) motors can't overspeed because the field is always present.
A shunt DC motor can overspeed if you lose field power but keep applying
armature power. Systems usually have some kind of interlock to prevent
this. For example, a relay coil in series with the shunt field, whose
contacts cut off armature power if field current is lost.
A series motor gets its field power from the armature current. At no
load, armature current approaches zero, so field current approaches
zero, and it can overspeed. A no-load series motor running at well under
its rated voltage (like 1/4th or less) will generally run very fast, but
not overspeed. Nuch above this, though, and you are in danger of it
rapidly disassembling itself!
There are several ways to "idiot proof" it. You can directly sense rpm,
and use it to cut back or turn off the controller. This could be as
simple as the centrifugal switch from an AC motor with a starting
winding.
Or, you can add a small shunt winding to the series motor. The shunt
winding is connected across the armature, to provide at least a weak
field so the motor won't overspeed. This is common in industrial EVs.
Or, you can use a circuit to sense the voltage drop across the
low-resistance series field. If the voltage drop gets too low, and there
is armature power, it operates a relay to reduce or cut power to the
motor. For example, my ComutaVan had a transistor circuit whose
base-emitter junction sensed field voltage. When this transistor was
"on", it operated a relay coil whose contact enabled the contactor
controller to switch to full voltage. If field current was too low,
field voltage was too low, so it wouldn't switch to full pack voltage.
> Curtis "C" series controllers operate at a reduced 1.5 kHz switching
> frequency up to 10% of throttle demand - preventing jerky starts, etc.
> Does this help with the no load DC motor behavior situation at all?
No. It's there to prevent excessive current on startup, but does nothing
to prevent overspeed.
> "This life's dim windows of the soul,
> distort the world from pole to pole,
> and causes one to believe a lie,
> when one sees with, and not through, the eye"
> - William Blake
A good quote!
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Dave Cover wrote:
> I have a Z1K and I plan on limiting the battery side amperage
> to 300 or so. When I first get the car on the road I will have
> 153 volts but will increase it to over 300 when I get more
> racks built.
> Now, taking an optimistic view of Rogers input, I could use a
> 250 amp, 125VDC 3 pole breaker wired through all three legs to
> handle the 300 volt pack.
A 250A Heinemann will do you fine, even if you crank the Z1K wide open.
With DC trip curve 01 (what is commonly available from EV supplieers),
it will carry 250A continuously, and will carry a 500% overload (about
1200A) for between 2.5 and about 12s. My controller is limited to about
500A, and my 250A Heinemann doesn't even notice (of course, my EV is
also light, so I don't tend to sustain 500A levels for more than a
second or two; just long enough for these spikes to show up in the
E-Meter log).
The single pole GJ1 breaker is the one most commonly available from EV
suppliers, and it is rated for 125VDC. If you can locate a GJ2 (2-pole)
version somewhere (industrial supplier?), it is good for 250VDC with
both poles in series. Basically you want the same part number as the
GJ1 (GJ1-B3-DU0250-01C), but with GJ2 at the start, so you get the same
trip curve and DC rating, etc.
It has been discussed before that it is arguably safe to use a slightly
under-rated breaker (voltage-wise) since the battery pack voltage will
sag significantly under the sort of load that will trip the breaker. I
don't know if your 300V+ NiCad pack will sag below 250V while heavily
loaded enough to trip the breaker, but it is certainly believable.
Square D has a number of 250A+ breakers UL listed for 125VDC, 250VDC,
and 500VDC, and a few that they self-certify at 300VDC and 600VDC. For
250VDC or higher, check out the Q4, KA, KD, KH, KJ, LAQ, LH, MA, amd MH
series molded case breakers to see which (if any) offer convenient
bolt-type connections like the Heinemanns do.
For voltages above 300VDC, the typical Square D recommendation is to
connect a 3-pole breaker such that the outer poles switch the positive
and negative connections to the load and the center pole divides the
pack in half.
Square D product bulletin D-453A lists their DC rated breakers and
provides the recommended wiring approach for the different breakers to
achieve the stated ratings.
Hope this helps,
Roger.
--- End Message ---
--- Begin Message ---
So that everyone knows I do sell Siemens type breakers brand new, you may
always contact me for a price and I will try and give anyone the best price
possible. The other option you have if would like a used breaker is to
contact one of my suppliers for Obsolete or used items that they stock. The
company is PM Sales in Chicago at 773-237-8211 and they stock all brands,
amperages, and types. The fact is I would love to sell everyone new
breakers but they are so expensive you can get used ones that do the same
job at a fraction of the price.
Hope this helps everyone and if anyone ever has breaker questions please
ask.
Regards,
Rick Todd
Peterson Electric Panel Mfg. Co.
Department of Engineering
5550 McDermott Dr.
Berkeley, IL 60163
Phone (708) 449-2270
Fax (708) 449-2269
Website www.petersonpanel.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Roger Stockton
Sent: Friday, June 16, 2006 2:21 PM
To: ev@listproc.sjsu.edu
Subject: RE: Circuit breaker question
Dave Cover wrote:
> I have a Z1K and I plan on limiting the battery side amperage to 300
> or so. When I first get the car on the road I will have
> 153 volts but will increase it to over 300 when I get more racks
> built.
> Now, taking an optimistic view of Rogers input, I could use a 250 amp,
> 125VDC 3 pole breaker wired through all three legs to handle the 300
> volt pack.
A 250A Heinemann will do you fine, even if you crank the Z1K wide open.
With DC trip curve 01 (what is commonly available from EV supplieers), it
will carry 250A continuously, and will carry a 500% overload (about
1200A) for between 2.5 and about 12s. My controller is limited to about
500A, and my 250A Heinemann doesn't even notice (of course, my EV is also
light, so I don't tend to sustain 500A levels for more than a second or two;
just long enough for these spikes to show up in the E-Meter log).
The single pole GJ1 breaker is the one most commonly available from EV
suppliers, and it is rated for 125VDC. If you can locate a GJ2 (2-pole)
version somewhere (industrial supplier?), it is good for 250VDC with both
poles in series. Basically you want the same part number as the
GJ1 (GJ1-B3-DU0250-01C), but with GJ2 at the start, so you get the same trip
curve and DC rating, etc.
It has been discussed before that it is arguably safe to use a slightly
under-rated breaker (voltage-wise) since the battery pack voltage will sag
significantly under the sort of load that will trip the breaker. I don't
know if your 300V+ NiCad pack will sag below 250V while heavily loaded
enough to trip the breaker, but it is certainly believable.
Square D has a number of 250A+ breakers UL listed for 125VDC, 250VDC, and
500VDC, and a few that they self-certify at 300VDC and 600VDC. For 250VDC
or higher, check out the Q4, KA, KD, KH, KJ, LAQ, LH, MA, amd MH series
molded case breakers to see which (if any) offer convenient bolt-type
connections like the Heinemanns do.
For voltages above 300VDC, the typical Square D recommendation is to connect
a 3-pole breaker such that the outer poles switch the positive and negative
connections to the load and the center pole divides the pack in half.
Square D product bulletin D-453A lists their DC rated breakers and provides
the recommended wiring approach for the different breakers to achieve the
stated ratings.
Hope this helps,
Roger.
--- End Message ---
--- Begin Message ---
> Chris Paine just sent me this link to a much more in-depth article in The
> Washington Post today titled: An Electric Car, Booted.
>
> http://www.washingtonpost.com/wp-dyn/content/article/2006/06/15/AR2006061502052.html
>
> Roderick Wilde
The promotter of this new film is really playing this like a fiddle, isn't
he? It's another regular "Hype of the Christ" or "Fahrenheit
$911(million)" publicity campaign. <g>
--- End Message ---
--- Begin Message ---
"Mark E. Hanson" wrote:
> I was curious why (in the textbooks & IR apps-notes) you always see
> a 2-switch fet drive with 2-diodes instead of a full H-bridge drive
> for a reluctance motor drive. Looks like a 2-switch forward converter.
> Would you get more power with a full bridge drive or would it cause
> other problems?
It has to do with cost/efficiency tradeoffs.
If cost is vital, you can use a single transistor (and single freewheel
diode) per coil. The voltage applied to that coil can go from 0 to 100%
of your pack voltage.
Note that it can't go negative; to run an AC motor this way, the best
you can do is apply a half-cycle pulse of AC to that winding, and coast
thru the other half cycle. It runs, but weakly. Your cheap 1-transistor
driver only gives you half the power the motor is capable of.
The next step up is to add a second winding, 180 degrees offset from
this first one, and powered with a second transistor. Electrically, it
looks like a center-tapped transformer winding. The transistors
alternately turn on, so only one is on at a time. By transformer action,
you now have both a positive and negative half-cycle in the winding, so
the motor develops more power. If there were room for two full-size
windings, you could get 100% of the motor's power. But in practice, each
winding has to be wound with half the wire size to make them both fit.
Doubling the resistance of each winding means you get more like 60%-70%
of the power the motor is capable of.
Another step up is to add two more transistors (four total), and drive
that single winding with an H-bridge. Now you have a normal single-phase
motor, and can get 80-90% of the motor's horsepower capability. But
being single-phase, it still has large torque pulsations.
So, they go up again, to add a second phase (another set of motor
windings, and the transistors to drive them. 2-phase motors can be quite
smooth, and give you almost the motor's full horsepower capability.
Finally, when efficiency becomes your goal, you go to a 3-phase motor,
with the required six driver transistors.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Peter VanDerWal wrote:
>
> > I remember his computer. Unfortunately, I don't think the C5 was brought
> > to
> > the US, except in rare cases. This car has a lot of Nerd appeal... and I
> > think it'd be perfect for Micro-car rallies.
>
> Not a lot of them made it to the US, but a few did. I have one, and I've
> heard about a couple others. Saw one on Ebay once, but it went for more
> than I was willing to part with at the time (Besides, I don't really need
> TWO of them)
I saw a Sinclair C5, and my impression was that it was more like a toy
than a serious vehicle. As with many of Clive Sinclair's products, they
combined incredibly brilliant ideas with incredibly cheesy
implementations.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
--- End Message ---
