EV Digest 6524
Topics covered in this issue include:
1) DTE Gauge (WAS: Electric Ford Ranger on E-bay)
by Bill Dennis <[EMAIL PROTECTED]>
2) RE: Heatsinking a Curtis
by "Roger Stockton" <[EMAIL PROTECTED]>
3) Re: Precharge Resistor Primer
by "Michaela Merz" <[EMAIL PROTECTED]>
4) case cooling (was RE: Motor blower)
by "Randy Burleson" <[EMAIL PROTECTED]>
5) RE: Kilovac EV-200 as safety disconnect?
by "Roger Stockton" <[EMAIL PROTECTED]>
6) Re: Precharge Resistor Primer
by "Richard Acuti" <[EMAIL PROTECTED]>
7) RE: Manual Transmission Rebuild
by Cor van de Water <[EMAIL PROTECTED]>
8) Re: Heatsinking a Curtis
by "Richard Acuti" <[EMAIL PROTECTED]>
9) Re: case cooling (was RE: Motor blower)
by KARSTEN GOPINATH <[EMAIL PROTECTED]>
10) Fw: wheel hub motor
by "FRED JEANETTE MERTENS" <[EMAIL PROTECTED]>
11) Re: case cooling (was RE: Motor blower)
by KARSTEN GOPINATH <[EMAIL PROTECTED]>
12) RE: Kilovac EV-200 as safety disconnect?
by Cor van de Water <[EMAIL PROTECTED]>
13) Re: My next EV project, or Paul goes Datsun
by "Paul G." <[EMAIL PROTECTED]>
14) Re: Motor mods
by "Paul G." <[EMAIL PROTECTED]>
15) Main fuse protects the safety contactor (was: Kilovac EV-200
as safety disconnect?)
by Bill Dube <[EMAIL PROTECTED]>
16) Re: Precharge Resistor Primer
by Lee Hart <[EMAIL PROTECTED]>
17) Re: FWD friction
by David Brandt <[EMAIL PROTECTED]>
18) Re: Kilovac EV-200 as safety disconnect?
by David Brandt <[EMAIL PROTECTED]>
19) RE: My next EV project, or Paul goes Datsun
by "Roger Stockton" <[EMAIL PROTECTED]>
20) Splitting a pallet of batteries
by "Matt Kenigson" <[EMAIL PROTECTED]>
21) Re: Heatsinking a Curtis
by Rod Hower <[EMAIL PROTECTED]>
22) Re: 300V EV Questions
by "FRED JEANETTE MERTENS" <[EMAIL PROTECTED]>
--- Begin Message ---
Here's an article on estimating DTE for Li-ion cells. Some of the info
may be applicable to other cell chemistries.
http://www.maxim-ic.com/appnotes.cfm/appnote_number/131
Bill Dennis
--- End Message ---
--- Begin Message ---
Phil Marino wrote:
> My guess is that the heat generating components are
> close to the end with the large power terminals.
> Is that right?
Nope. ;^>
The power devices are in a line from on end to the other, and somewhat
toward the centerline of the controller from the edge of the case
opposite the edge with the small fastons for the potbox/KSI (i.e. to the
right of center, viewing from the end with the terminals).
They are attached to a heat spreader that distributes the heat more or
less across the bottom of the Curtis case baseplate.
Roughly centering your little heatsink lengthwise under the Curtis,
perhaps shifted slightly to the right is probably about as good as
you'll get.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
> A precharge circuit is any circuit that allows the controller's
> capacitors to be charged up to pack voltage *before* the contactor
> closes. Usually, it is nothing but a resistor and a small switch or
> relay, closed for a second or so to charge up the capacitors.
Hmm ... and what would be the value of that resisitor?
mm.
--- End Message ---
--- Begin Message ---
> My LeSled EV (Lectric Leopard based on Renault LeCar, but
> using 120V of floodeds) is inching toward full-time use.
> After my close-to-home trials the motor is usually too
> hot to leave my hand on it.
Adding a blower or driving in a different gear make sense... a cheap bit
of dryer hose affixed to channel air from a high-pressure area like the
front of the car may also help, and dryer hose is pretty cheap.
Something you may also be able to do is add fins to the motor to help it
dissipate heat faster. I added something similar to a winch motor, and
it seems to have extended the operational window for that motor. Tough
to say for sure, since my winch pulls are hardly consistent or
repeatable, but it makes intuitive sense and looks kinda cool, to boot.
The heat sink that I found and used was from my Table Top Patio Heater
(clamps to the outside of the mini propane tank to prevent freeze-up) --
it actually fits well around the 8274-50 winch motor. It looks like a
typical finned aluminum heat sink, but is thin enough and annealed so
that it can be easily wrapped around the motor, with the fins left
standing perpendicular to the housing (since it is so soft, it is kind
of delicate, though). I think you could do something similar by folding
a thick foil (/\/\/\/\/\/\)and drilling one edge of the folded stack for
zip ties, and then using those ties to clamp it in place around the
motor.
Randii
--- End Message ---
--- Begin Message ---
David Brandt wrote:
> Unless the EV200 was bad to begin with.
It is difficult to envision a defect that would result in failure in
just 5 cycles when a relay rated to carry multiple hundreds of amps
continuously is doing the same job as a 10A relay, but you seem to have
ruled out the possibility of misapplication and infant mortality does
seem like the next likely cause.
I don't suppose you dissected the defective part out of curiousity?
Perhaps something obvious would be evident, such as the blow out magnets
missing or misinstalled?
> "If the EV200s were closing in the proper sequence, then the contactor
> that should see the most stress is actually the second one to
> close..."
>
> Agreed. However, it shouldn't have been under too much stress either.
Maybe, maybe not; depending on the logic that pulls in the second
contactor it might have been under more than you think. You mention
that when the voltage reached a set level around 90%, a relay pulled in
the second contactor. If the set threshold was at about 90% of the
nominal voltage of a 144V pack (so the relay would pull in even when the
pack nears complete discharge), then that threshold would correspond to
less than 84% of the pack voltage just off charge. The Kilovac data
sheet shows a 1000x reduction in switching life between 90% and 80%
precharge, so this could still translate to a significant reduction in
the contactor life. Still, this contactor didn't give you any problems,
so its life was still something greater than 5 cycles ;^>
> "Actually, the newer LEV200 is only 3" tall vs 2.04-2.2" for the older
> EV200, and carries identical ratings. It is grouped under "Aerospace,
> Ground Power and Industrial High Performance Contactors", but is
> identified as an "Industrial DC Contactor"."
>
> That's the one I was thinking of. So it has about a 30%
> increase in height. That's significant.
Not actually. If you compare the two, you'll notice that the shorter
one had a bulge on the side (presumably for the coil econimiser
circuit), while the longer one appears to have moved this circuitry
inside allowing a simple cylindrical, but longer body. Indeed, the
longer body model has stud connections for the coil on the top, which
suggests there may be more distance between the switch terminals and the
switch element than on the shorter body version, which could result in
different (poorer) heat dissipation characteristics.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Wow. Timely info for me again.
I'm running a 128v system with a 120v Curtis. When I bought the car I was
informed about the pre-charge setup and I have 2 household lightbulbs
installed. I was told to use the pre-charge switch before turning the key to
avoid damaging the controller. Now I know how and why.
Rich A.
Message-ID: <[EMAIL PROTECTED]>
Date: Wed, 07 Mar 2007 07:52:06 -0800
From: Eric Poulsen <[EMAIL PROTECTED]>
MIME-Version: 1.0
To: [email protected]
Subject: Re: Precharge Resistor Primer
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Nutshell version:
Your controller contains capacitors (which store a charge) to smooth out
the ripple current; most power supplies and power conversion devices
(like motor controllers) have them. When the controller has been off
for a while, the capacitors are in a discharged state. The nature of
capacitors is that they act just like a short circuit very briefly when
exposed to a DC voltage in an discharged state. This causes a large
current spike (and maybe an arc, or damage to wires, caps, contactor,
etc) when the contactor is closed.
The solution is to "pre-charge" the capacitors at a slower rate through
a resistor, so that the capacitor voltage is close to the battery pack
voltage when the contactor closes, reducing the current surge to
something relatively small.
The Curtis potbox switch is a safety feature (whose merits are sometimes
"discussed" on this list) which opens the main contactor when the
throttle is completely let off. The idea being that if you have a
failure condition in the controller where it cannot turn off because of
shorted transistors or whatnot, that when you take your foot off the
accelerator, the contactor will open and de-energize the controller.
During normal driving, the contactor will click off every time the
throttle is let up, but the precharge circuit remains active, so the
caps don't discharge.
_________________________________________________________________
Mortgage rates as low as 4.625% - Refinance $150,000 loan for $579 a month.
Intro*Terms
https://www2.nextag.com/goto.jsp?product=100000035&url=%2fst.jsp&tm=y&search=mortgage_text_links_88_h27f6&disc=y&vers=743&s=4056&p=5117
--- End Message ---
--- Begin Message ---
Mark,
My suggestion: go for it!
Since you have the factory manual, you should be able to figure
things out when you open it up and avoid most errors by following
the manual in the first place.
If you feel unsure, go back and read the manual once more next to
the opened transmission.
If you feel you are not up to the task with the transmission opened,
you can always undo what you did, bolt it back together and don't
worry about torque specs, just make everything slightly more than
hand-tight and the rebuild shop will take care of it.
If you get everything apart and can fix the issues you find,
then it is time to buy a torque wrench if you want to do it right.
BTW, I have never owned or used a torque wrench, although I have
taken the head off an engine and put it back together and drove
it for months before selling it.
Most torque specs from manufacturers are just a way to make sure
it is reproducible, but with some "feeling" you have a good
chance of tightening bolts to a level that is safe and sane.
Success,
Cor van de Water
Systems Architect
Proxim Wireless Corporation http://www.proxim.com
Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [EMAIL PROTECTED]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Second Life: www.secondlife.com/?u=3b42cb3f4ae249319edb487991c30acb
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Mark Farver
Sent: Wednesday, March 07, 2007 10:42 AM
To: [email protected]
Subject: Manual Transmission Rebuild
So I pulled the MR2 transmission last weekend and set it off to a
transmission shop up here in Austin. They do not even have the tools to
open it, and they don't have the time to haul it to a shop that specializes
in manual transmissions. They asked me to come get it, and gave me the name
of the company (Pistole, in South Austin) that they would usually sub the
work out to.
The transmission has two problems, a bad 3rd gear syncro (much needed) and a
metallic rattle that sounds like some loose piece is falling to the bottom
of the transmission whenever the vehicle comes to a halt.
So now I have a choice, do I haul the tranny to the South end of town and
pay for a rebuild, or do I do the rebuild myself.
1. I never even opened a transmission before, and the diagrams make it look
tremendously complex inside.
2. I lack all of the tools required, (including a inch/lb accurate torque
wrench and a bearing press) as well as several special service tools.
OTOH,
1. I may save a little money now, and certainly will save money if I ever
have to do this again 2. I can modify the transmission for a electronic
speed sensor, and maybe even remove unneeded gears like first.
3. The factory manual I have covers the entire process, and is very
complete.
Thoughts? Anyone ever done this before?
Mark Farver
--- End Message ---
--- Begin Message ---
When I owned my Comuta Van, someone replaced the contactor controller array
with a 1221B. They mounted it to a plastic surface with no cooling ability
at all. Even at only 72 volts, in the summer hill climbing would make it
shift into overheat cutback.
I strapped a large stereo amplifier heatsink to the top of it and it make a
world of difference even though the bottom of it wasn't mounted to any heat
absorbing surface.
Even though the controller in my new EV is mounted to a large metal surface,
it worked so well that I'm thinking of doing it again anyway. Heat is the
enemy. I found it on eBay. Just check there or the EV trading post in the
parts for sale area.
Rich A.
Message-ID: <[EMAIL PROTECTED]>
From: "Phil Marino" <[EMAIL PROTECTED]>
To: [email protected]
Subject: Heatsinking a Curtis
Date: Wed, 07 Mar 2007 16:09:44 -0500
Mime-Version: 1.0
Content-Type: text/plain; format=flowed
I'm mounting my Curtis ( 1221C) to a flat aluminum plate ( 3/16 x 14 x 16
inches) as a heatsink, but I also have a smaller, finned heatsink ( about 5
x 7 x 2 inches) that I want to mount to the back side of the plate.
(opposite side as the controller) for a bit of extra cooling.
I may as well put it close to where the heat is generated on the Curtis"
base - it would probably be a bit more effective. My guess is that the heat
generating components are close to the end with the large power terminals.
Is that right?
Does anyone know where the internal heat-generating components are? Or, have
a picture of the guts of a 1221C that would show that?
Thanks
Phil
_________________________________________________________________
Mortgage rates as low as 4.625% - Refinance $150,000 loan for $579 a month.
Intro*Terms
https://www2.nextag.com/goto.jsp?product=100000035&url=%2fst.jsp&tm=y&search=mortgage_text_links_88_h27f6&disc=y&vers=743&s=4056&p=5117
--- End Message ---
--- Begin Message ---
I don't know the circumference of your motor, but I once used a heat
trapping device for a camping stove as a heat sink. It clamps around
the pot and is made by MSR.
On Mar 7, 2007, at 3:51 PM, Randy Burleson wrote:
My LeSled EV (Lectric Leopard based on Renault LeCar, but
using 120V of floodeds) is inching toward full-time use.
After my close-to-home trials the motor is usually too
hot to leave my hand on it.
Adding a blower or driving in a different gear make sense... a cheap
bit
of dryer hose affixed to channel air from a high-pressure area like the
front of the car may also help, and dryer hose is pretty cheap.
Something you may also be able to do is add fins to the motor to help
it
dissipate heat faster. I added something similar to a winch motor, and
it seems to have extended the operational window for that motor. Tough
to say for sure, since my winch pulls are hardly consistent or
repeatable, but it makes intuitive sense and looks kinda cool, to boot.
The heat sink that I found and used was from my Table Top Patio Heater
(clamps to the outside of the mini propane tank to prevent freeze-up)
--
it actually fits well around the 8274-50 winch motor. It looks like a
typical finned aluminum heat sink, but is thin enough and annealed so
that it can be easily wrapped around the motor, with the fins left
standing perpendicular to the housing (since it is so soft, it is kind
of delicate, though). I think you could do something similar by folding
a thick foil (/\/\/\/\/\/\)and drilling one edge of the folded stack
for
zip ties, and then using those ties to clamp it in place around the
motor.
Randii
--- End Message ---
--- Begin Message ---
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* ---REMAINDER OF MESSAGE TRUNCATED--- *
* This post contains a forbidden message format *
* (such as an attached file, a v-card, HTML formatting) *
* Lists at sjsu.edu only accept PLAIN TEXT *
* If your postings display this message your mail program *
* is not set to send PLAIN TEXT ONLY and needs adjusting *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
--- End Message ---
--- Begin Message ---
pic of heat exchanger. pretty cheap.
http://www.msrcorp.com/cookware/heat_exchanger.asp
On Mar 7, 2007, at 4:10 PM, KARSTEN GOPINATH wrote:
I don't know the circumference of your motor, but I once used a heat
trapping device for a camping stove as a heat sink. It clamps around
the pot and is made by MSR.
On Mar 7, 2007, at 3:51 PM, Randy Burleson wrote:
My LeSled EV (Lectric Leopard based on Renault LeCar, but
using 120V of floodeds) is inching toward full-time use.
After my close-to-home trials the motor is usually too
hot to leave my hand on it.
Adding a blower or driving in a different gear make sense... a cheap
bit
of dryer hose affixed to channel air from a high-pressure area like
the
front of the car may also help, and dryer hose is pretty cheap.
Something you may also be able to do is add fins to the motor to help
it
dissipate heat faster. I added something similar to a winch motor, and
it seems to have extended the operational window for that motor. Tough
to say for sure, since my winch pulls are hardly consistent or
repeatable, but it makes intuitive sense and looks kinda cool, to
boot.
The heat sink that I found and used was from my Table Top Patio Heater
(clamps to the outside of the mini propane tank to prevent freeze-up)
--
it actually fits well around the 8274-50 winch motor. It looks like a
typical finned aluminum heat sink, but is thin enough and annealed so
that it can be easily wrapped around the motor, with the fins left
standing perpendicular to the housing (since it is so soft, it is kind
of delicate, though). I think you could do something similar by
folding
a thick foil (/\/\/\/\/\/\)and drilling one edge of the folded stack
for
zip ties, and then using those ties to clamp it in place around the
motor.
Randii
--- End Message ---
--- Begin Message ---
I read somewhere that the reason for good specs in small package of the
Czonka
is the use of a specific gas inside the enclosure.
Could it have been yours was cracked/leaking and therefor welded shut?
NOTE that is may have been welded for months without you knowing, as the
only way to find that a contactor does not disconnect is if the
controller actually checks the voltage level ABSENT before closing the
first (pre-charge) contactor (you can test this by quickly turning the
key off and on - if your controller throw an error "voltage present where
there should be none", then it is checking for absence of HV)
You might also see a small drain from your controller being permanently
powered, but if you drive your EV daily, this may go unnoticed as the
12V will be disconnected, so the HV is likely not or hardly loaded.
If this was the problem then it became very apparent when your controller
failed full-on and you could not break the pack voltage with your contactor.
Regards,
Cor van de Water
Systems Architect
Proxim Wireless Corporation http://www.proxim.com
Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [EMAIL PROTECTED]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Second Life: www.secondlife.com/?u=3b42cb3f4ae249319edb487991c30acb
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of David Brandt
Sent: Wednesday, March 07, 2007 3:01 PM
To: [email protected]
Subject: Re: Kilovac EV-200 as safety disconnect?
Roger wrote:
"Is there any possibility that you had one of the contactors wired in
reverse polarity? Not the coil, but the main contacts; they are polarised,
and the switch life is *dramatically* reduced if connected in reverse
polarity. According to the datasheet, life is about 12 cycles @ 200A if
connected in reverse polarity vs 50,000 at about 350A when used in the
correct orientation, according to the 90% precharge capacitive inrush spec."
Nope. I observed the polarity markings.
"Are you sure your precharge circuit was working the way you intended?
This failure is also what one would expect if, for example, the contactor
with the precharge relay were closing immediately, and the one without was
then closing afterwards."
Nope, they closed in the proper sequence, with about a 2 second delay.
"In a nutshell, the contactor with the precharge resistor across it couldn't
possibly precharge anything unless the other contactor was closed first, and
if the first one closes while the other is open, then it could not see much
of an inrush at all."
Yes. The one without closed first. A relay then closed to apply power to
the second when the controller voltage rose to a set level. I don't
remember where I had it set, but it was at least 90%.
"Many precharge systems actually use a small 10A (P&B KUEP, etc) relay in
series with the precharge resistor so that when the ignition is off the
controller is completely disconnected from the traction battery, and if
these little relays can handle the inrush that your first EV200 would be
switching, then there is no way the EV200 can't."
Unless the EV200 was bad to begin with.
"If the EV200s were closing in the proper sequence, then the contactor that
should see the most stress is actually the second one to close..."
Agreed. However, it shouldn't have been under too much stress either.
> The newer EV-200 model (I forget the model designation - You can
> probably find it on the tyco electronics website) is twice as tall. I
> suspect they had minimal gaps and realized that to market the new
> model for aircraft, as they do, that they had to have better
> reliability, so they increased the travel of the contacts.
"Actually, the newer LEV200 is only 3" tall vs 2.04-2.2" for the older
EV200, and carries identical ratings. It is grouped under "Aerospace,
Ground Power and Industrial High Performance Contactors", but is identified
as an "Industrial DC Contactor"."
That's the one I was thinking of. So it has about a 30% increase in height.
That's significant.
"The CAP200 appears to be the aerospace counterpart and MAP200 is the
MIL/aerospace counterpart. Both of these parts appear to have similar
dimensions as the smaller EV200 rather than the larger LEV200 part..."
I wonder what aerospace companies have used it and if they have had good
reliability.
____________________________________________________________________________
________
Get your own web address.
Have a HUGE year through Yahoo! Small Business.
http://smallbusiness.yahoo.com/domains/?p=BESTDEAL
--- End Message ---
--- Begin Message ---
On Mar 6, 2007, at 5:40 PM, Roger Stockton wrote:
Cool project choice! In all honesty, when I clicked on the link to see
the first EV part installed, I fully expected to see a picture of the
nut behind the wheel ;^>
Thank you (I think ;-)
I drove a '74 B210 during high school, after the rear end went on the
prior owner. Even with the absolutely gripless BFG tires I was
running,
I managed to go through another rear end in short order. While there
are enough years separating this car from yours that the similarity
between them may be slight, my experience would lead me to doubt the
stock differential's ability to cope with spirited EV driving. The
4-speed in my B210 was trouble-free, for what that is worth.
No, I've got some small parts under there. The rear axle from an SSS
411 would fix up the back and there are lots of transmissions
available. So long as I stay under 100 ft/lb. of torque I stay roughly
inside the ratings of what I have now. I'll start there and see if I
can keep from turning up the screws <g>. (come to think of it, that
could be a real problem with me and a sep-ex setup)
[snip]
This seems ideal for a pack of the group 34 Optimas; the rear box is
just enough space to hold 8 YTs comfortably, leaving just 5 to stuff
under the hood. The underhood 24"x24" space could hold as many as 6
YTs
(pushing you up to 168V), but with the master cylinder cutting in 5 may
be more realistic.
It looks like you have been eyeing my sketches! I have some drawing of
a 22.5" by 21.5" box minus a 7" by 7" corner for the front. I have a
rough idea for a 29" wide by 21.5" box with a center reinforcement for
the rear. The idea is that I can fit either 10 group 31 AGMs (4 front,
6 rear) or 13 group 34 AGMs (5 front, 8 rear.)
A little trip down memory lane...
Shortly after I found the EV list I went to my first EVent, the
Portland EV Awareness Day 1998. At this show I found a few list members
everyone knows, like Madman, Plasma Boy, Father Time, and Wild Man.
John (Plasma Boy) was at the show with several vehicles, in particular
he had an early version of Baby Blue, a '68 Datsun 520 Pickup (front
end looks familiar :-) Anyway, it was put together with 10 (or perhaps
11) YT Optimas in a box at the front of the bed, an ADC 9 inch motor,
and an older Curtis 1221b (keeping with John's quest for *quiet*)
controller. John had showier cars there too, but that one struck me
with its simplicity. I was an EV newbie and I could follow it easily.
Now I happen to have a Curtis 1221b on my garage shelf (in addition to
the one in my Buggy.) I'm tempted to make the same combo in my Datsun
411. With adaptable battery boxes I could go 156v and Zilla in the
future (after a few drive train parts are upgraded too!) I'm not to
concerned about the nose weight. In fact, the stock Datsun 411 is less
than 60% over the front tires stock (I need to watch rear weight more.)
I'm confident that the front can handle around 200 extra pounds without
any changes (me sitting on the radiator bulkhead adds almost that) and
I have over 300 lb. of ICE stuff to pull (motor dry is 292 lb. plus 18
lb. for the cooling system dry, plus water and oil.)
Is there any hope of putting a couple under the rear seat to keep the
underhood area from getting cluttered (and the front end too heavy)? 5
YTs and an ADC 8" would put close to 350lbs under there.
There is the possibility of getting batteries (in more elaborate
crafted boxes) under front and rear seats. As I tear the vehicle down I
will be checking more closely. It has a lot to do with mapping where
the important bits are under the car into the under-seat area inside
the car. It would be more work, but could allow as many as 8 concealed
batteries.
You didn't mention what your range requirements are.
Short - the first duty will be to take my commute miles off of my 2004
Tacoma. That is 4 miles each way and way to many cold starts for good
ICE life (I keep changing the oil because 6 months has passed - and it
doesn't even have 2000 miles on it.) By the time I get to a solid 12
mile range (meaning in the rain and without being careful about the
trip) I can use it for almost everything around town.
Wheel selection is somewhat limited but the bolt pattern and
required offset is the same as a Geo Metro (4 lug on a 4.5 inch
pattern, about +38 offset.)
It might not be that bad. The 4x114.3mm pattern (and required offset)
gives you 13x4.5 and 14x5 wheels from the Switft/Metro, or 13x5, 14x6,
and 15x6 from the Honda Accord or '92-on Prelude, 14x6 from the pre-85
Toyota Celica (offset may be a bit lower than desired), or 13x5.5
(Mazda
GLC or pre-'90 323), or 14x5.5 from the 84-88 RX7 GSL/SE or 83-87 626.
Thank you. That is a nice list of potential wheels. Now there is one
last issue - center hub diameter. I need a full 70mm - this thing has
large front hubs. Your list has already added possible choices to what
I had found. I'm still looking for hub diameter information, and of
course I have to concern myself with stud size too (in my case 12mm by
1.25mm pitch - fairly common.) The one aftermarket wheel I posted has a
72.6mm hub in both 13 inch and 14 inch diameters and is listed for a
Geo Metro (and the 4 cylinder models had 12mm studs - or bolts.)
[snip]
Thank you,
Paul "neon" G.
WAR IS PEACE
FREEDOM IS SLAVERY
IGNORANCE IS STRENGTH
George Orwell, "1984"
--- End Message ---
--- Begin Message ---
On Mar 7, 2007, at 7:46 AM, Jim Husted wrote:
I have been known to snap that last bolt
from time to time, of course it's always the last one
I'm doing, just to make it all that more difficult to
redo.
Well I hope its the last one!! What point would tightening the rest be
after you break one. LMAO
Wait - I better be careful... (I may some of Jim's work, crap, now
he's going to charge me double) XOXO <g>
Paul "neon" G.
--- End Message ---
--- Begin Message ---
You need to size the main fuse to protect the safety contactor. The
main fuse must blow before enough current flows to weld the safety
contactor shut.
Most folks don't give this much thought, but it is vitally important
for safety.
Way back when Moses was a boy, (and I was NEDRA Tech Director) I
wrote about this in the NEDRA safety rules.
Here is the quotation:
>>>>>>>>>
The 2001 NEDRA rules require that not only must the pack be protected
from over-current, the main (safety) disconnect must also be
protected from overcurrent damage. The same protection device (fuse
or breaker) can serve both functions. The continuous current rating
of the protection device must less than or equal to the continuous
current rating of the main (safety) disconnect.
It is important to note that not only the continuous carry current of
the fuse should be less than the rating of the contactor, but the
carry current curve of the fuse should lie completely below the carry
current curve of the contactor.
>>>>>>>>
If you had a main fuse, it likely had a carry current higher than the
carry current of the safety contactor. Typically, you need a
"semiconductor" type fuse. Look at the spec sheet on your contactor
and then compare the contactor carry current curve (or data points)
to the carry current curve on you main fuse.
Bill Dube'
At 04:24 PM 3/6/2007, you wrote:
David Brandt wrote:
> When I was running the escort (114V system of floodies with a
> Curtis 1221b), I had 2 EV-200's in series. The second in
> line was shorted by a precharge resistor, and a circuit would
> close that contactor when the system was precharged. So
> there was minimal inrush current. The first one welded shut
> after about 5 cycles and I had to replace it. If they do
> this on a system this far under their specs, I wouldn't use
> them again.
Is there any possibility that you had one of the contactors wired in
reverse polarity? Not the coil, but the main contacts; they are
polarised, and the switch life is *dramatically* reduced if connected in
reverse polarity. According to the datasheet, life is about 12 cycles @
200A if connected in reverse polarity vs 50,000 at about 350A when used
in the correct orientation, according to the 90% precharge capacitive
inrush spec.
Are you sure your precharge circuit was working the way you intended?
This failure is also what one would expect if, for example, the
contactor with the precharge relay were closing immediately, and the one
without was then closing afterwards.
In a nutshell, the contactor with the precharge resistor across it
couldn't possibly precharge anything unless the other contactor was
closed first, and if the first one closes while the other is open, then
it could not see much of an inrush at all.
Many precharge systems actually use a small 10A (P&B KUEP, etc) relay in
series with the precharge resistor so that when the ignition is off the
controller is completely disconnected from the traction battery, and if
these little relays can handle the inrush that your first EV200 would be
switching, then there is no way the EV200 can't.
If the EV200s were closing in the proper sequence, then the contactor
that should see the most stress is actually the second one to close...
> The newer EV-200 model (I forget the model designation - You
> can probably find it on the tyco electronics website) is
> twice as tall. I suspect they had minimal gaps and realized
> that to market the new model for aircraft, as they do, that
> they had to have better reliability, so they increased the
> travel of the contacts.
Actually, the newer LEV200 is only 3" tall vs 2.04-2.2" for the older
EV200, and carries identical ratings. It is grouped under "Aerospace,
Ground Power and Industrial High Performance Contactors", but is
identified as an "Industrial DC Contactor".
The CAP200 appears to be the aerospace counterpart and MAP200 is the
MIL/aerospace counterpart. Both of these parts appear to have similar
dimensions as the smaller EV200 rather than the larger LEV200 part...
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
>> A precharge circuit is any circuit that allows the controller's
>> capacitors to be charged up to pack voltage *before* the contactor
>> closes. Usually, it is nothing but a resistor and a small switch or
>> relay, closed for a second or so to charge up the capacitors.
From: Michaela Merz <[EMAIL PROTECTED]>
>Hmm ... and what would be the value of that resisitor?
It's not at all critical. Curtis recommends 250 to 750 ohms, depending on the
controller. The switch that you have in series with it (to turn on the
precharge) sets the minimum resistance; if it is rated for (say) 1 amp, and
your pack is 144v, then the resistor can be as small as R = 144v/1amp = 144
ohms.
The maximum value is set by how long you are willing to let it precharge. For
example, the Curtis 1221B has 32 x 220uF = 7040uF. The precharge time time is
about 2RC. So a 144 ohm resistor precharges in T = 2 x 144ohms x 0.007040uF = 2
seconds. A 1440 ohm resistor would take 20 seconds, etc.
--
Lee Hart
--- End Message ---
--- Begin Message ---
Disconnect the brake calipers and hang them oput of the way then try again.
You will know for sure if it is the brakes, and how bad it is.
One thing that was probably different, though - you probably tried the ICE with
the tranny in neutral. Did you do the same with the EV?
David Brandt
----- Original Message ----
From: Claudio Natoli <[EMAIL PROTECTED]>
To: [email protected]
Sent: Wednesday, March 7, 2007 1:47:04 AM
Subject: FWD friction
Hi all,
at the Sydney AEVA workshop last night, I mentioned the EVDL's "1-finger push
test", which our vehicle (Daihatsu Charade) certainly fails.
One thing I've noticed is that, with the front wheels elevated and with the
gearbox in neutral, hand spinning the front (drive) wheels takes considerable
effort. It is difficult to get them up to any sort of speed (ie. 1 rev / sec),
and they stop in a quarter turn or so. By comparison, I recently had
opportunity to try the same thing with an original ICE variant owned by a
friend, and it was considerably easier, and the drive wheel would spin for a
few seconds from a similar speed.
This of course sparked a great deal of curiosity at the workshop, so we jacked
up the front (drive) wheels of our EV, and everyone had a go at turning the
front wheels with a view to seeing whether they thought the friction was high
or normal for a FWD. Typically, opinions varied considerably.
I was therefore wondering whether other owners of FWD EVs, or those with
similar experience, could chip in their 0.2 kh.hrs worth? Does this sound
normal for a FWD? Should the drive wheels spin more freely? Could choice of
gearbox oil, which is the simplest thing for me to change, have a dramatic
impact?
Depending on comments I'll probably try changing out the oil in the gearbox on
the weekend. While I'm working on the car, is there anything else that I could
check? There are any numbers of contributors (gearbox, wheel-bearings,
dragging brakes, ...), but is there a simple way to differentiate to identify
the biggest culprits?
Cheers,
Claudio
Sydney AEVA - for Electric Vehicle enthusiasts in Sydney, Australia
http://sydneyaeva.googlepages.com/
____________________________________________________________________________________
No need to miss a message. Get email on-the-go
with Yahoo! Mail for Mobile. Get started.
http://mobile.yahoo.com/mail
--- End Message ---
--- Begin Message ---
Cor wrote:
"I read somewhere that the reason for good specs in small package of the
Czonka
is the use of a specific gas inside the enclosure.
Could it have been yours was cracked/leaking and therefor welded shut?"
Yes, they use hydrogen. That is a possibility I hadn't considered, and in
response to Roger's question, no I didn't take it apart to determine the
problem. I was much too frustrated for that. Oh, and that was on a 114V pack,
not 144V.
"NOTE that is may have been welded for months without you knowing..."
No, I checked it's operation before connecting pack voltage.
", as the
only way to find that a contactor does not disconnect is if the
controller actually checks the voltage level ABSENT before closing the
first (pre-charge) contactor (you can test this by quickly turning the
key off and on - if your controller throw an error "voltage present where
there should be none", then it is checking for absence of HV)
You might also see a small drain from your controller being permanently
powered, but if you drive your EV daily, this may go unnoticed as the
12V will be disconnected, so the HV is likely not or hardly loaded."
This was a homebuilt precharge circuit used with a curtis. I don't think the
terms 'curtis' and 'error code' go together ;-)
"If this was the problem then it became very apparent when your controller
failed full-on and you could not break the pack voltage with your contactor."
I did not have a controller failure. I believe it was Lawrence that did.
____________________________________________________________________________________
8:00? 8:25? 8:40? Find a flick in no time
with the Yahoo! Search movie showtime shortcut.
http://tools.search.yahoo.com/shortcuts/#news
--- End Message ---
--- Begin Message ---
Paul G. wrote:
> Thank you. That is a nice list of potential wheels. Now
> there is one last issue - center hub diameter. I need a
> full 70mm - this thing has large front hubs. Your list
> has already added possible choices to what I had found.
> I'm still looking for hub diameter information, and of
> course I have to concern myself with stud size too (in
> my case 12mm by 1.25mm pitch - fairly common.)
All of those I listed should be for 12mm studs.
I'm not positive about the centerbore, but if I'm reading the numbers
right, the Suzuki Swift/Metro and Toyota Celica are just 60.1mm. The
Mazda wheels drop to 59.6mm, Honda and Acura options increase to 64.1mm.
Nissan and Infiniti possibilities are a bit higher yet, at 66.1mm, and
the Kia and Mitsubishi are the largest option at 67.1mm. (Yes, these are
additional possibilites for 4x114.3 bolt pattern 13-15" wheels.)
Perhaps the wheels have enough additional clearance in practice that
some will fit over your monster hubs!
Good luck,
Roger.
--- End Message ---
--- Begin Message ---
Howdy,
Looks like I'm less than a month away from finally having the resources to
get a new pack for my baby. While I'm not against other options, I'll
probably get another 20 T-125s. I've heard from others on the list that you
can get a significant discount by ordering them by the pallet-load (40
batteries). I was wondering if anyone out there is willing to go in on a
pallet with me. I'm in Nashville Tennessee so it would probably work out
best with someone in the Southeast. I'm going to Florida next week (Ocala,
Tampa, and Orlando) but I doubt I could get the batteries that fast, anyway
(unless there's a Trojan dealer in Florida who stocks them or a warehouse
somewhere in between).
Anyway, is anyone out there interested? If there's someone out there that
was about to buy a pack of something different (that isn't a lot more money)
I might be interested as well.
Matt Kenigson
austinev.org/evalbum/882
--- End Message ---
--- Begin Message ---
I've never done a thermal analysis of the Curtis, but
this is what the heatsink looks like,
| | | |
| | | |
| | | |
____ ____ ___
_________________
Kind of a U shape with MOSFETs and diodes mounted
vertically and a heat spreader at the bottom that
mounts to the extruded case with an isolated Sil-pad.
The U shape with heat spreader is also an extruded
piece. My guess is a uniform plate on the bottom of
the case will work. I don't think thermal transfer is
really fast between the U shaped extruded part and the
base. Extended high current situations will require
appropriate cooling, probably just a finned heatsink
and you could also use a fan to increase cooling.
Otmar has a much better cooling layout with huge
copper water cooled plates that remove heat much
quicker from the semiconductors.
Have fun,
Rod
--- Phil Marino <[EMAIL PROTECTED]> wrote:
> I'm mounting my Curtis ( 1221C) to a flat aluminum
> plate ( 3/16 x 14 x 16
> inches) as a heatsink, but I also have a smaller,
> finned heatsink ( about 5
> x 7 x 2 inches) that I want to mount to the back
> side of the plate.
> (opposite side as the controller) for a bit of extra
> cooling.
>
> I may as well put it close to where the heat is
> generated on the Curtis"
> base - it would probably be a bit more effective.
> My guess is that the heat
> generating components are close to the end with the
> large power terminals.
> Is that right?
>
> Does anyone know where the internal heat-generating
> components are? Or, have
> a picture of the guts of a 1221C that would show
> that?
>
> Thanks
>
> Phil
>
>
_________________________________________________________________
> Mortgage rates as low as 4.625% - Refinance $150,000
> loan for $579 a month.
> Intro*Terms
>
https://www2.nextag.com/goto.jsp?product=100000035&url=%2fst.jsp&tm=y&search=mortgage_text_links_88_h27f6&disc=y&vers=743&s=4056&p=5117
>
>
--- End Message ---
--- Begin Message ---
why are u putting the circuit breakers in series for ? it will not chNGE THEIR
VOLTAGE RATING AS THEY ARE NOT A LOAD . AND BEING IN SERIEA THEIR CURRENT
RATING WILL NOT CHANGE EITHER .
----- Original Message -----
From: Adrian DeLeon<mailto:[EMAIL PROTECTED]>
To: [email protected]<mailto:[email protected]>
Sent: Wednesday, March 07, 2007 12:43 AM
Subject: 300V EV Questions
EV #2 is going to be a Toyota pickup conversion. 15-20 mile typical range
at 30-45MPH, relatively hilly terrain. I'd like some suggestions on the
following options:
1) 9" vs 11" motor. I'm thinking 11" because of the hills. My 50A @ 30MPH
VW takes 150-200A to maintain 30MPH on certain road sections. The 11"
should deliver higher torque (at lower RPM) for chugging uphill and have
more power for (occasionally) hauling stuff.
2) 156V vs 300V battery pack. 156V = 26 x 6V floodies. 300V = 25 x Group
31 AGM, possibly Deka GELs. I know AGMs=$$$, but low maintenance and
higher power are tempting. This will be my wife's truck, so the closer it
matches the original ICE "feel" the better.
Contactor: Kilovac EV200/250 (nice discussion recently).
Circuit breaker: 3 Heinemann/Airpax 160V breakers in series w/ trip
handles tied together?
Relays for heater or DC/DC: Another Kilovac? A FET switch with appropriate
fusing? I can't find any relays for 300VDC @ 5-10A.
Finally: Any issues using a stock Warp9 or Warp11 with a 300V pack and
Zilla 1K? (Other than the impact on my wallet?)
-Adrian
.
--- End Message ---
