EV Digest 4061
Topics covered in this issue include:
1) Re: ETEK problem found.
by "Rich Rudman" <[EMAIL PROTECTED]>
2) RE: people willing to buy EVs OT: NiZn batteries
by "Roger Stockton" <[EMAIL PROTECTED]>
3) Re: Nevercells
by "Rich Rudman" <[EMAIL PROTECTED]>
4) RE: Zilla /palm (better serial terminal?)
by Otmar <[EMAIL PROTECTED]>
5) RE: Zilla /palm (better serial terminal?)
by "Jamie Marshall \(GAMES\)" <[EMAIL PROTECTED]>
6) Re: Zilla /palm (better serial terminal?)
by "Ryan Stotts" <[EMAIL PROTECTED]>
7) Re: Zilla/Palm
by Ryan Bohm <[EMAIL PROTECTED]>
8) Re: Zilla /palm (better serial terminal?)
by "Ryan Stotts" <[EMAIL PROTECTED]>
9) Re: people willing to buy EVs OT: NiZn batteries
by Victor Tikhonov <[EMAIL PROTECTED]>
10) RE: Zilla /palm (better serial terminal?)
by Otmar <[EMAIL PROTECTED]>
11) Re: Fuse placement
by Victor Tikhonov <[EMAIL PROTECTED]>
12) Re: people willing to buy EVs OT: NiZn batteries
by David Dymaxion <[EMAIL PROTECTED]>
13) RE: Zilla /palm (better serial terminal?)
by "Steve Marks" <[EMAIL PROTECTED]>
14) Re:
by Victor Tikhonov <[EMAIL PROTECTED]>
15) Re: Zilla /palm (better serial terminal?)
by Otmar <[EMAIL PROTECTED]>
16) High voltage EV audio system
by Ryan Bohm <[EMAIL PROTECTED]>
17) Re: homen made contactor
by Lee Hart <[EMAIL PROTECTED]>
18) Re: ETEK problem found.
by Ken Trough <[EMAIL PROTECTED]>
19) RE: Zilla interface future.
by Otmar <[EMAIL PROTECTED]>
20) Re: High voltage EV audio system
by Victor Tikhonov <[EMAIL PROTECTED]>
21) Re: homen made contactor
by James Massey <[EMAIL PROTECTED]>
22) Re: Fuse placement
by James Massey <[EMAIL PROTECTED]>
23) Re: Zilla interface future.
by Neon John <[EMAIL PROTECTED]>
24) RE: Zilla interface future.
by "Don Cameron" <[EMAIL PROTECTED]>
25) RE: Zilla interface future.
by "Steve Marks" <[EMAIL PROTECTED]>
26) Myth about Shelf Life of LiIon
by Edward Ang <[EMAIL PROTECTED]>
27) Re: High voltage EV audio system
by =?ISO-8859-1?Q?Jukka_J=E4rvinen?= <[EMAIL PROTECTED]>
28) My Battery Pack Specifications
by James D Thompson <[EMAIL PROTECTED]>
29) Re: ETEK problem found. (extreem cooling?)
by Lightning Ryan <[EMAIL PROTECTED]>
--- Begin Message ---
----- Original Message -----
From: "Neon John" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, January 28, 2005 10:23 AM
Subject: Re: ETEK problem found.
> Uh, do any of you guys realize that there is nothing on the ETEK to attach
> any sort of monitoring device to? The field is PM. The rotor and
> commutator are effectively one and the same. There is probably an inch of
> clearance between the end bars and the frame. By the time the frame even
> gets warm the rotor will be slagged.
>
> The only possible way to monitor the brazed end bars is with an IR
> pyrometer. Those are cheaply available but IMHO, not worth the effort.
>
> The way to make an ETEK survive is to limit the current. An ETEK isn't a
> hunk of pig iron like an ADC or a forklift motor. There is almost no
> thermal mass so even momentary overloads can cause damage.
>
> BTW, those end bars are sil-phos brazed. Sil-phos requires no flux for
> copper/copper joints and is a very common method of making internal motor
> connections. It is available from most any HVAC distributor. Do not
> confuse it with phos-copper. Lacking any silver, this alloy is of much
> higher resistance.
>
> Sil-phos melts at a dull red heat. The overcurrent must have been huge.
> Like someone else said, you must monitor and limit MOTOR current and not
> battery current. Motor current can be twice or more what the battery
> current is.
>
> John
> ---
> John De Armond
> [EMAIL PROTECTED]
> http://bellsouthpwp.net/j/o/johngd/
> Cleveland, Occupied TN
>
Twice???? In my life it's 4 to 10 times... or more.
I have data on 6x.....
Eteck's don't have much R or uH at all.
--- End Message ---
--- Begin Message ---
John Westlund [mailto:[EMAIL PROTECTED] wrote:
> The Evertroll NiZn could push up to 500 amps, 400 amps
> routinely without being harmed. From what I've read in the
> archives, a 336V pack pulling 400 amps would sag to about 220
> volts. Push it up to 500 amps and Evercel's quoted 280 watts
> per kilogram specific power figure seems accurate, although I
> wouldn't really push them to their limits to keep from damaging them.
220V @ 400A is 88kW or 118 battery HP. And you're close to loading the
Evercels to 1/2 nominal voltage, so this is close to the maximum power
you can get. Pull 500A and the voltage will sag a bit more, but power
will probably increase somewhat.
Read Rich's warning though: 300-500A will overheat NiZn in *seconds*.
Who ran a 336V string of NiZn and pulled 400A from them?
> If I'd have used smaller more expensive
> 40 pound batteries, I could have a 336V pack, 26 kWh, and
> about 130 horsepower from 1120 pounds of batteries.
Probably not, since the smaller batteries would sag even more at the
same load, which would reduce your battery HP.
> I'd have at least 120 peak horsepower at the motor, as long
> as the motor is getting 1,000 amps of current, about 220
> lb-ft of torque.
How do you figure? What is the efficiency of your motor at 1000A?
Probably down around 50-70% at best, and you've only got <130 battery HP
to throw at it... this means an absolute maximum of mechanical 90HP
before drivetrain losses (at 1000A). Peak efficiency is around 85%, so
the best you could get, again before drivetrain losses, is about 110HP
assuming 130 battery HP.
> My main concern with PbA is range. I don't know what to
> expect. On one side, we have Rich Rudman's Goldie, with 192V
> of Orbitals, only getting 20 miles if driven carefully,
Rich's data is for Goldie with 156V of Optimas; I believe his Orbitals
are still being cycled in.
Here's another data point for you: Paul 'Neon' Gooch's Manx-style dune
buggy with 120V of Optimas also reported a drop-dead range of about 20mi
despite the aerodynamics of a brick (it does make up for it somewhat
with *extremely* low rolling resistance).
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Sorry we could not publish the draw down curves at the time.
But.. we could get to about 350 amps, but with sever temp rise rates. You
got about 30 seconds and were at our max temps limits.
So...500 amps was a sever risk. I did it once....
Lets move on..this is history.
--- End Message ---
--- Begin Message ---
Otmar,
Do you have some formalization of the command set the Zilla implements
so it can be called programmatically? That is, is there a better way
than just writing out to a serial port the commands the Zilla accepts
and parsing out the text that it would otherwise return to a Palm Pilot?
SteveM
http://www.ghiamonster.com
Hi Steve,
At this time the Hairball only has text interface, since it's
intended for humans to be able to read and adjust.
I have no plans to do such a interface for limited use, but I'd be
happy to do it if it promoted some greater good. If someone wrote and
donated a nice GUI for the Palm (or a better platform) that would
allow people to adjust values, record and review data with just
stylus clicks, then I'd be happy to write code to enable a easier
interface for such applications. Binary maybe?
I've had dreams of such a interface for many years. I even started to
write one in CodeWarrior for the Palm, but that was over 6 years ago.
It got too complicated for the time I had available.
No offence, but I'd have to see a nice demo first. I've spent way too
much time waiting for programmers to actually do a project to be the
first one to put time into it. :-)
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
I used to have a PDA called a psion 3.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=38331&item=574762
4928&rd=1&ssPageName=WDVW
This one is only 20 bucks. You could get a serial cable for it, though
it was not just a cable, it may have had some logic in there. It came
with a terminal program, and was a very nice piece of work.
-Jamie
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Otmar
Sent: Friday, January 28, 2005 10:01 AM
To: [email protected]
Subject: Re: Zilla /palm (better serial terminal?)
>I am trying to change some setting on my Zilla and have a palm , . I'm
>at the last part where I've picked a new number , got it in and it says
>"enter amps 250 " but I can't find enter anywhere , looked on keybord ,
>tried all the othere bottens , hitting most just puts me back to the
>begining , . I tryed other setting and always get to the same point ,
>where it say enter xxx then the number I put in , STeve Clunn
Hi Steve,
After typing the value of the current you want, it wants a "return" key.
I usually use the Graffiti input on the Palm to enter data so I didn't
realize that this can be a place to get stuck until recently when I
tried to teach Dennis how to do this. We discovered that when using the
"KBD" option to enter data, the "return" key does not work.
So this is one key that you'll need to learn to do in Graffiti.
Graffiti is the name of the Palms handwriting recognition system.
To type a "return" in Graffiti you need to draw a slash from the upper
right to the lower left of the text entry area. Like a normal "/". The
text entry area is the lower left "box" that has "abc"
printed in the lower left corner of it. Give that a try and see if it
works for you.
The Palm also has a pretty good tutorial program on how to write
Graffiti. I find it easy to use for most entries. The program is called
Graffiti and you can get to it by hitting the picture of a house, and
then the icon called Graffiti.
hth,
btw, for you techies out there. I sure wish I knew of a better serial
communication system for entering data in the Hairball. A keyboard, no
matter how small would be great, and at least 12 lines of display.
It needs to be able to talk rs-232 serial even after replacing dead
batteries without needing to be connected to a computer. Of course it
needs to be inexpensive as well. This is for those customers who don't
regularly use computers. So far the Palm is the best thing I've found,
but it does not have a keyboard, and the add on keyboards seem to use up
the serial port to function.
Any leads/ideas would be much appreciated.
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
In regards to the serial connection, what about long term?
Years from now. Have you looked into USB or Firewire?
As for serial, it would be interesting to know where this
"Ford dealership" gets their serial interface device made
at:
http://www.andersonfordmotorsport.com/pms/pms-50.html
--- End Message ---
--- Begin Message ---
Hi Steve, and everyone else,
I had this problem too. In the scribble area, if you make a diagonal mark from
one corner of the writing area to the other, it will send a return. I don't
remember which corner it is, but if you do the graffiti tutorial on your Palm,
it will show you how to make it. I get confused even more because I have my
Palm mounted sideways. I have a Palm Hackmaster program (FlipHack) that
rotates the screen, but it doesn't rotate the graffiti area (that's another
extension). I mostly use the pop-up keyboard to enter numbers, and then do the
diagonal mark to get the enter. Let me know if you need better instructions.
I'm not driving the car today :( It's still out for my cabling repair/upgrade.
Good luck,
Ryan
----- Original Message -----
From: "Steve Clunn"
To:
Sent: Friday, January 28, 2005 9:15 AM
Subject: Zilla /palm
> I am trying to change some setting on my Zilla and have a palm , . I'm at
> the last part where I've picked a new number , got it in and it says
"enter
> amps 250 " but I can't find enter anywhere , looked on keybord , tried all
> the othere bottens , hitting most just puts me back to the begining , . I
> tryed other setting and always get to the same point , where it say enter
> xxx then the number I put in ,
> STeve Clunn
--- End Message ---
--- Begin Message ---
>No offence, but I'd have to see a nice demo first. I've
>spent way too
>much time waiting for programmers to actually do a project
>to be the
>first one to put time into it. :-)
>
>-Otmar-
Maybe have someone write your dream program for a small
fee....
http://www.bookofhook.com/Article/GameDevelopment/MyOff-ShoreProgrammingExp.html
It's worth a look..
--- End Message ---
--- Begin Message ---
John Westlund wrote:
Seth Allen wrote:
If Victor knows a NiZn solution with prices/quality similar
to Evertrolls, or maybe even someone offering usable
Evertrolls themselves, I'd be gladly interested to see it.
Omeone sent me an email saying that he bought (or was going to)
NiZn from a warehouse sime in Texas where they stock them.
HAve no idea if this is remaining stock and Evercel no
longer exist, or they resumed operation.
If I'll find that email, I'll forward it to the list.
Victor
--- End Message ---
--- Begin Message ---
I used to have a PDA called a psion 3.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=38331&item=574762
4928&rd=1&ssPageName=WDVW
This one is only 20 bucks. You could get a serial cable for it, though
it was not just a cable, it may have had some logic in there. It came
with a terminal program, and was a very nice piece of work.
I've thought of them. Nice little device. I sure wish they were still made.
Finding one is not too hard, but I need something where I can be sure
to find at least 50. Otherwise the support would become a nightmare.
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
I think he meant the fuse in half the string sees half the
voltage in case if *both* ends of that battery half
(say, one box) gets shorted to the frame for example.
Then, *this* box's fuse goes kaboom, but he other half
stay intact. Only half of the string (one battery box, not
two) worked to blow this fuse.
Of course if you only disconnect a series string, the voltage
between ends of disconnected string is always at full pack,
but that is not the only potential danger, and he described
*other* failure possibility.
Victor
Roland Wiench wrote:
Try this by experimentation:
Connect a string of batteries in series and connect it to a load, like a
light bulb. If you break the connection any where in the circuit and read
the voltage, the voltage will read the same!
The voltage reading should be less than the battery pack voltage, because
you have a resistance or load in the circuit. Something like a voltage
divider circuit.
Roland
----- Original Message -----
From: "Seth Allen" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, January 28, 2005 6:28 AM
Subject: Re: Fuse placement
Yep, it is clearer now, thanks.
Seth
On Jan 28, 2005, at 2:39 AM, James Massey wrote:
At 08:07 AM 27/01/05 -0500, you wrote:
Ok, I never really thought about it, but aren't you first and third
paragraphs contadictory? After thinking about it, I could certainly
be misinformed, but after reading your post, I know I am confused. At
any rate, I still think it is a good place to fuse. But that's a free
opinon, so you get what you paid for it.
Seth
Sorry, didn't mean to confuse, although I admit to being good at it.
I'll try and clarify:
A short will end up with full voltage across the fuse, wherever in
the loop it is.
If you have (for example) a 120V pack with a fuse in the middle, you
have made it up by putting (+) to (-) of a string of modules. Imagine
that you now remove the fuse and put the pack (+) connected to the
pack (-). Now you have 120V across the fuse position (and the same
condition as if the fuse was only at one end of the string). This is
what would happen if you get a short outside the battery pack between
pack (+) and pack (-). So the fuse has to clear 120V in the event of
an external short.
Mid-pack is good, to halve the maximum voltage between any two
points (and used for final install point on assembly),
If you *do not* attach pack (+) to pack (-), and you remove a fuse
from the middle of a string, then you will have a maximum voltage
between any two points in the pack of half pack voltage. This makes it
safer to work on, mostly by halving the possible places you can
accidentally touch to get shocked.
Hope this makes sense.
James
--- End Message ---
--- Begin Message ---
For ~$6k:
About 900lbs of Nimh batteries from wrecked hybrids. I calculated
about double the range of lead, and a bit less power than lead.
About 900 lbs of little nicads: About 1.5 times the range of lead and
a little better power than lead (for low resistance nicads). Only
ones in this price range are generics like at
http://www.powerstream.com , going to Sanyos would triple the cost or
more.
=====
__________________________________
Do you Yahoo!?
Yahoo! Mail - You care about security. So do we.
http://promotions.yahoo.com/new_mail
--- End Message ---
--- Begin Message ---
Is throughput an issue through the Zilla's serial port? Could you
support an XML based interface in addition to the current teletype
interface? That way GUIs could be developed irrespective of the current
interface's design and it wouldn't fall on you to support them. Changes
to your teletype interface wouldn't have to affect the behavior of the
GUIs, unless they broke the XML interface which can be avoided with a
good design. This is what I meant by formalizing the interface.
Steve
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Otmar
Sent: Friday, January 28, 2005 11:47 AM
To: [email protected]
Subject: RE: Zilla /palm (better serial terminal?)
Hi Steve,
At this time the Hairball only has text interface, since it's
intended for humans to be able to read and adjust.
I have no plans to do such a interface for limited use, but I'd be
happy to do it if it promoted some greater good. If someone wrote and
donated a nice GUI for the Palm (or a better platform) that would
allow people to adjust values, record and review data with just
stylus clicks, then I'd be happy to write code to enable a easier
interface for such applications. Binary maybe?
I've had dreams of such a interface for many years. I even started to
write one in CodeWarrior for the Palm, but that was over 6 years ago.
It got too complicated for the time I had available.
No offence, but I'd have to see a nice demo first. I've spent way too
much time waiting for programmers to actually do a project to be the
first one to put time into it. :-)
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
The information contained in this email message is being transmitted to and is
intended for the use of only the individual(s) to whom it is addressed. If the
reader of this message is not the intended recipient, you are hereby advised
that any dissemination, distribution or copying of this message is strictly
prohibited. If you have received this message in error, please immediately
delete.
--- End Message ---
--- Begin Message ---
John Westlund wrote:
Maybe I've been lusting over Wayland's Insight proposal for
too long then. With aero upgrades done to many EVs, my
planned GT6 conversion would be about as aerodynamic, with
such a small 15 square foot frontal area. Stock Cd is only
32.
Gary Graunke has done about what John Wayland was proposing,
and I believe is pretty happy with outcome.
Not quite the same drive system (better matching Insight
in my view), but use lead for now waiting for LiIons.
Evercells are way too bulky for such a tiny car, even though
are light.
You need to pick the battery with better volumetric energy
density than NiZn ones. With high enough voltage, battery power
is not taht much of a concern - NiZn easily would pull Insight
as battery currenct would never exceed 150A or so.
(Statement does not apply to John of course).
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
I am trying to change some setting on my Zilla and have a palm , . I'm at
the last part where I've picked a new number , got it in and it says "enter
amps 250 " but I can't find enter anywhere , looked on keybord , tried all
the othere bottens , hitting most just puts me back to the begining , . I
tryed other setting and always get to the same point , where it say enter
xxx then the number I put in ,
STeve Clunn
Hi Steve,
I've learned a new trick!
I was just discussing this with another customer who has a
preprogrammed Palm from me. He mentioned that he had the same problem
and was trying out all kinds of things. He eventually stumbled upon
this solution:
Press the lower right button on the Palm. (yes, the notepad button)
It's as simple as that. When I programmed the Palms, I also set the
settings so that pressing the lower right button brings up ptelnet
instead of the notepad. What I didn't know is that when you press
that button it also sends a "return" or "enter", I don't know which.
But it works and doesn't require remembering which way to make the
slash mark in Graffiti.
hth,
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
Hi Everyone,
John Wayland - this post is for you! :)
This is way out in dream-land, but a quiz just got canceled at school which
gave my brain some free-time. If you wanted to put in an awesome stereo
system, you'd have to get beefier DC/DC's...or why couldn't someone put out a
high-voltage audio amp? Anyone know of something like that? I could see a
niche market there - EV's with kicking stereo systems. It would be the new fad
:) Every low-rider would be selling their rig to get an EV. Who cares if it
only goes 20 miles, it blows all the other stereo systems away!
-Ryan
--- End Message ---
--- Begin Message ---
brian baumel wrote:
> does any one have suggestions on where I could get
> affordable contacts to make my own contactor relay?
Sure; you can buy replacement contacts for most standard contactors.
--
Ring the bells that you can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in
-- Leonard Cohen, from "Anthem"
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
would it be worth monitoring the motor temperature ?
Probably not, but it WOULD be worth installing a squirrel cage fan as
Roderick suggested. A tiny bit of forced air cooling goes a whole heck
of a long way toward keeping a motor cool. That and he definitely needs
to improve his gear ratio. He is clearly overloading the motor when
hillclimbing. I don't believe he kept his motor under the rated amp
limit as he thinks. Did he have an ammeter on it at the time? If he
didn't, he doesn't know what kind of power the motor was under when it
failed.
Lawrence: if you want a super reliable ride, spend the money to replace
your motor (instead of trying to bodge something together to limp it
down the road under repair), add the fan as Roderick suggested, and
improve your gear ratio. If you had done this to begin with, your first
motor would still be kickin, most likely.
There are definitely times when cobbing together a cheap/free ride out
of used parts is advantageous. The smaller, slower, lower power scooters
are much more forgiving. Not rides at these power levels though. Do it
right from the start, and you'll have a ride you can count on.
Hope this helps!
-Ken Trough
Admin - V is for Voltage Magazine
http://visforvoltage.com
AIM - ktrough
FAX - 801-749-7807
message - 866-872-8901
--- End Message ---
--- Begin Message ---
At 1:43 PM -0800 1-28-05, Steve Marks wrote:
Is throughput an issue through the Zilla's serial port?
Depends what scale you are thinking of. It runs at 9600 baud. Faster
would be a problem.
Could you
support an XML based interface in addition to the current teletype
interface? That way GUIs could be developed irrespective of the current
interface's design and it wouldn't fall on you to support them. Changes
to your teletype interface wouldn't have to affect the behavior of the
GUIs, unless they broke the XML interface which can be avoided with a
good design. This is what I meant by formalizing the interface.
I'm not at all familiar with XML. I've heard the term a few times,
but I've never read up on any details.
I suspect I could allocate half a K of ROM to such a interface. Do
you think XML is the kind of thing that could be implemented in 500
bytes of ROM?
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
Then, it doesn't have to be an EV at all, if nicest stereo is
the only goal.
As of high voltage - use tube amplifier. No beefy DC-DC needed.
The sound from tubes is also unbeatable according to audiophiles.
But, who am I to comment on sound stuff? I don't even have a
radio in ACRX, and don't really miss it. A car is not the place
to really listen to music, the music there is to keep you from
being bored while driving. And, of course, to brag about hardware.
But that is just an opinion and about OT.
Victor
Ryan Bohm wrote:
Hi Everyone,
John Wayland - this post is for you! :)
This is way out in dream-land, but a quiz just got canceled at school
which gave my brain some free-time. If you wanted to put in an
awesome stereo system, you'd have to get beefier DC/DC's...or why
couldn't someone put out a high-voltage audio amp? Anyone know of
something like that? I could see a niche market there - EV's with
kicking stereo systems. It would be the new fad :) Every low-rider
would be selling their rig to get an EV. Who cares if it only goes
20 miles, it blows all the other stereo systems away!
-Ryan
--- End Message ---
--- Begin Message ---
At 09:33 AM 28/01/05 -0800, brian baumel wrote:
does any one have suggestions on where I could get
affordable contacts to make my own contactor relay? I
have a few solenoids laying around and $50+ seems a
little much for something I should be able to make
myself easy enough .....
Hi Brian
Contacts? easy, buy spares for a manufactured item.
Solenoids you have laying around? Aaahh... Before you start, consider the
following:
Are they continuous duty?
Can they supply enough force to hold the contacts against each other, and
the necessary large return spring for the high-power contacts?
Do they have enough stroke length to open the contacts far enough to get
safe opening distance?
Can you get enough voltage rating between the contacts and the solenoid body?
There are things that you can do to help the situation. If you increase the
opening distance, you can use a coil 'slugger' circuit running from a
higher-than-original voltage to make them pull in cleanly. You can add
magnetic blowouts to help the opening voltage.
I'm sure that Lee Hart has more things that you need to consider, but it
would be helpful to know what you are intending to use your home-made
contactor for. If you are looking to use it/them for traction use, then
spend you saved money by buying a quality emergency disconnect. I would
think that you would consider your life to be worth more than $50US?
Just my $0.02Aus (about $0.016US)
James (Who *always* wants to make it himself, but thinks through and asks
questions, then usualy thanks Lee yet again).
--- End Message ---
--- Begin Message ---
At 09:31 AM 28/01/05 -0800, Lee Hart wrote:
This is true if there is *nothing* connected between pack+ and pack-.
But (for example) I have a little switching power supply across my pack
to provide power for the E-meter. It only draws a few ma, but...
<snip> Hah! I got bit when I went to put the fuse back! Full pack voltage
(132vdc in my case).
Moral: *Always* disconnect your safety switches and fuses, even if you
don't think you need to!
Which is why I'm putting pull-out fuses in pack+, pack- and mid-pack. The
more convenient it is to pull the disconnects, the more likely it is to
happen.
The mid-pack fuses are mostly due to having two independent strings,
connected at pack+ and pack-. A serious imbalance between strings (a
serious module failure) dictates a minimum of a fuse that is relative to
the two strings (a fuse that when blown disconnects one string from the
other). And since I have enough fuses and holders, then two went in (for
the half-voltage safety reason).
James.
--- End Message ---
--- Begin Message ---
On Fri, 28 Jan 2005 14:21:07 -0800, Otmar <[EMAIL PROTECTED]> wrote:
>I'm not at all familiar with XML. I've heard the term a few times,
>but I've never read up on any details.
>
>I suspect I could allocate half a K of ROM to such a interface. Do
>you think XML is the kind of thing that could be implemented in 500
>bytes of ROM?
No, definitely not. XML is one of those faddish solutions that is mostly
looking for a problem. Think "very verbose, slobbery HTML".
XML is, IMHO, little more than a conspiracy to sell faster hardware, more
memory and more bandwidth. Definitely NOT applicable here.
Here's a little sample from NewsBin Pro's filter file:
<?xml version='1.0' encoding="ISO-8859-1" standalone="yes"?>
<Root>
<DEFAULT>
<MaxSpammer>10</MaxSpammer>
<MaxSize>0</MaxSize>
<MinSize>0</MinSize>
<FileAccept>
</FileAccept>
<FileReject>
</FileReject>
<SubjectAccept>
</SubjectAccept>
<SubjectReject>
<R>air america radio</R>
<R>allen robert</R>
</SubjectReject>
<UseFileReject>0</UseFileReject>
<UseFileAccept>0</UseFileAccept>
<UseSubjectReject>1</UseSubjectReject>
<UseSubjectAccept>0</UseSubjectAccept>
</DEFAULT>
</root>
FWIW, the techinque I use with embedded systems I design where both a
terminal and machine interface is necessary is to assign a unique number
to each output line and each command. Something like this:
<1> file menu
<2> open file
<3> save file
<4> delete file
<5> rename file.
Each command is also assigned a globally unique number. If there is a
user on the terminal, he can either enter the first letter of the command
or the number. frequently used commands that are down several menu levels
can be executed directly by number. I provide a command to change the
dialog from "verbose" (human readable) to "compact" (numbers only).
An application on the other end of the interface can either parse the
numbers and ignore the text or can put the interface into "compact" mode.
This is nice when the bandwidth of the interface is close to being used
up.
In the embedded system you end up with one large table of sentences and
another of responses that can be indexed into very quickly.
There are, of course, a lot of weaknesses to this simple protocol.
Dropped or munged characters, for example. As fast as the processors are
even in a Palm, I have not found that to be a problem at 9600 or lower.
John
---
John De Armond
[EMAIL PROTECTED]
http://bellsouthpwp.net/j/o/johngd/
Cleveland, Occupied TN
--- End Message ---
--- Begin Message ---
What I find is useful, if the controller or device could simply output
well-published ASCII information, then it is easy for a palm, PocketPC,
computer, etc. to read. XML is a little overkill for the output of a
device.
As an example, lets say the controller output the amount of volts and amps.
In simple ASCII format (the <cr> and <lf> are bytes to indicate the ASCII
code for the next line), it may look like:
V240<cr><lf>
A110<cr><lf>
V240<cr><lf>
A105<cr><lf>
V240<cr><lf>
A100<cr><lf>
.
.
.
In XML, it might look like:
<controller><volts value=240 /><amps value=110></controller>
<controller><volts value=240 /><amps value=105></controller>
<controller><volts value=240 /><amps value=100></controller>
.
.
.
XML is much nicer to read, and much easier for PC or PocketPC or Palms to
read, but at 9600 baud it will be slow. An this is only for two parameters.
Now if you do run into memory constraints, scrap the ASCII and go straight
for binary output. A lot of devices do this and it is not too bad.
Continuing with the above example, in hex:
56 00 F0
41 00 6E
56 00 F0
41 00 69
56 00 F0
41 00 64
.
.
.
These are 3 bytes records. The first byte identifies the record (56 is the
ascii hex for V, 41 is the ascii hex for A), then followed by a two byte
integer for the volts and amps. For negative value you can use either 1s or
2s complement.
Regaurless of which way you go (XML, ASCII or binary), then this will make
it easier for anyone to interface to your device, and you will not have to
manage or create a user interface.
Don
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Otmar
Sent: January 28, 2005 2:21 PM
To: [email protected]
Subject: RE: Zilla interface future.
At 1:43 PM -0800 1-28-05, Steve Marks wrote:
>Is throughput an issue through the Zilla's serial port?
Depends what scale you are thinking of. It runs at 9600 baud. Faster would
be a problem.
>Could you
>support an XML based interface in addition to the current teletype
>interface? That way GUIs could be developed irrespective of the
>current interface's design and it wouldn't fall on you to support them.
>Changes to your teletype interface wouldn't have to affect the behavior
>of the GUIs, unless they broke the XML interface which can be avoided
>with a good design. This is what I meant by formalizing the interface.
I'm not at all familiar with XML. I've heard the term a few times, but I've
never read up on any details.
I suspect I could allocate half a K of ROM to such a interface. Do you think
XML is the kind of thing that could be implemented in 500 bytes of ROM?
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
Wow, a whole half a K! I feel like a king! =o)
Actually, I suppose it *could* be implemented in half a K. The largest
consumer of memory would probably just be the tag names.
I'm using the term XML here pretty loosely. Basically, I just mean
marked up text. For instance, the following might be a stream of XML
that an application could send the Zilla to tell it to set the Motor Amp
Limit to 800 amps, the Battery Voltage Limit to 170 volts and return
with the current Motor Voltage Limit:
<SET><MAL>800</MAL><BVL>170</BVL></SET><GET><MVL/></GET>
To which the Zilla might respond:
<MVL>150</MVL>
For this interface you'd need storage space for the SET, GET, MAL, BVL
and MVL tags plus some simple parsing code. Depending on the number of
tags and how terse you can keep their text, it might just fit in that
space.
Note, since every XML operation begins with a '<' character, your
teletype interface could simply forward any string received to the XML
parser if it began with '<' and process the others the same as it does
now. The result would be two separate interfaces simultaneously
available. The XML interface could even be tested through the teletype
interface by having the user type the XML in directly, though I can't
imagine the graffiti stroke that does <, / and > ;o)
Steve
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Otmar
Sent: Friday, January 28, 2005 2:21 PM
To: [email protected]
Subject: RE: Zilla interface future.
At 1:43 PM -0800 1-28-05, Steve Marks wrote:
>Is throughput an issue through the Zilla's serial port?
Depends what scale you are thinking of. It runs at 9600 baud. Faster
would be a problem.
>Could you
>support an XML based interface in addition to the current teletype
>interface? That way GUIs could be developed irrespective of the
current
>interface's design and it wouldn't fall on you to support them.
Changes
>to your teletype interface wouldn't have to affect the behavior of the
>GUIs, unless they broke the XML interface which can be avoided with a
>good design. This is what I meant by formalizing the interface.
I'm not at all familiar with XML. I've heard the term a few times,
but I've never read up on any details.
I suspect I could allocate half a K of ROM to such a interface. Do
you think XML is the kind of thing that could be implemented in 500
bytes of ROM?
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
The information contained in this email message is being transmitted to and is
intended for the use of only the individual(s) to whom it is addressed. If the
reader of this message is not the intended recipient, you are hereby advised
that any dissemination, distribution or copying of this message is strictly
prohibited. If you have received this message in error, please immediately
delete.
--- End Message ---
--- Begin Message ---
I have never believed that the capacity of LiIon
decreases regardless of usage because I have a
9-year-old Sony camcorder with LiIon batteries that
are still good. So, I did a test.
I have 2 batteries -- 1 high capacity and 1 original.
I did not use the original batteries very often. Over
the past 9 years, I would say it has been used only
about 10-20 cycles. This battery is a SONY NP-F330
7.2V 5.0Wh (translate to about 0.694Ah). Today, I did
a discharge test using a light bulb to 3V per cell.
This is what I got.
0.6487Ah or 4.671Wh over 138mins
It still has 93% of its original capacity! I think it
is just another LiIon myth.
Ed Ang
__________________________________
Do you Yahoo!?
Take Yahoo! Mail with you! Get it on your mobile phone.
http://mobile.yahoo.com/maildemo
--- End Message ---
--- Begin Message ---
This is one of the best sides of EVs. Why waste 100 kW to moving when
you can get it out from speakers... *WHATAM*... and windshiled blops out
by the air pressure... And then....
WHAT !! I cant hear you !!..
I SAID DID YOU SEE THE THAT !! WOW!!
WHAT!!! I STILL CANT HEAR YOU!!
(And both guys have EV grin for LIFE.. No matter brain and ear damages..
other one lacks already and other has no reason since the first thing is
missing..)
I might have earlier mentioned the Subaru Elcat EV. Basicly it is quite
crappy car but would make a perfect stereo on wheels... Sound like a
project to me...
-Jukka
fevt.com
p.s.- And again I see why to install 200 pcs 5000 F ultracaps to car ;)
p.p.s.- Could someone please make a car that goes by sound to next
Woodburn ? Gotta see it run...
Ryan Bohm kirjoitti:
Hi Everyone,
John Wayland - this post is for you! :)
This is way out in dream-land, but a quiz just got canceled at school which
gave my brain some free-time. If you wanted to put in an awesome stereo
system, you'd have to get beefier DC/DC's...or why couldn't someone put out a
high-voltage audio amp? Anyone know of something like that? I could see a
niche market there - EV's with kicking stereo systems. It would be the new fad
:) Every low-rider would be selling their rig to get an EV. Who cares if it
only goes 20 miles, it blows all the other stereo systems away!
-Ryan
--- End Message ---
--- Begin Message ---
Just for kicks, I'm going to throw this out to see if anything exists
that can meet it.
13,000 wh deliverable to @80% DOD, voltage sag to no less than 260 volts
300+ nominal voltage
300a peak discharge for 15 seconds, voltage sag to no less than 80%
100a continuous discharge
operate as above from -10 to 50 degrees C
800 pounds maximum weight
$1.75 per amp-hour maximum cost, including BMS, etc.
David Thompson
--- End Message ---
--- Begin Message ---
Sorry to hear about your ETEK failure.
Does anyone happen to have photos of the insides of these motors?
How about a proper dis-assembly method?
I've been thinking about ETEK cooling methods, the most obvious
method being a fan attached to the brush housing, as Roderick warns.
This method is a must have, and good for everyday commuting. but...
What if you were to pre-cool the motor! Say by packing dry ice
(solid CO2 at -109 F (-78 C)) arround the motor! Of course you
need proper ventilation so that the sublimating CO2 gasses don't
build up in a passanger compartment. How well would this work?
I'm thinking that for starters the motor will have to
rise about 200 degrees before it even begins to get hot.
Also, does the lower temp increase the conductivity of
the windings, so you start out with better effeciency?
How would these low temps effect the megnetics of the motor?
L8r
Ryan
--- End Message ---
