EV Digest 4613
Topics covered in this issue include:
1) Re: e-meter type gadget wish list wanted.
by Ryan Stotts <[EMAIL PROTECTED]>
2) Re: Best method. 50% / 30 sec CC (was: Correct AGM finish
charge)
by "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
3) RE: e-meter type gadget wish list wanted.
by "Don Cameron" <[EMAIL PROTECTED]>
4) RE: Russco vs Zivan vs PFC
by "Don Cameron" <[EMAIL PROTECTED]>
5) Re: Russco vs Zivan vs PFC
by Ryan Stotts <[EMAIL PROTECTED]>
6) Re: Best method. 50% / 30 sec CC (was: Correct AGM finish charge)
by Ryan Stotts <[EMAIL PROTECTED]>
7) Sept. 3rd Electric Breakfast in Portland! (was woodburn)
by John Wayland <[EMAIL PROTECTED]>
8) Re: e-meter type gadget wish list wanted.
by Ryan Stotts <[EMAIL PROTECTED]>
9) Re: Sept. 3rd Electric Breakfast in Portland! (was woodburn)
by Ryan Stotts <[EMAIL PROTECTED]>
10) Re: Russco vs Zivan vs PFC
by Ryan Stotts <[EMAIL PROTECTED]>
11) Re: e-meter type gadget wish list wanted.
by Mike Chancey <[EMAIL PROTECTED]>
12) Re: Sept. 3rd Electric Breakfast in Portland! (was woodburn)
by keith vansickle <[EMAIL PROTECTED]>
13) Re: Plus and Minus Together
by James Massey <[EMAIL PROTECTED]>
14) Re: e-meter type gadget wish list wanted.
by Ryan Stotts <[EMAIL PROTECTED]>
15) RE: Who's Using Marathon NiCads?
by "Bill Dennis" <[EMAIL PROTECTED]>
16) Re: Plus and Minus Together
by Ryan Stotts <[EMAIL PROTECTED]>
17) Battery design
by "Michaela Merz" <[EMAIL PROTECTED]>
18) Re: Valence Lithium-ion
by "Andrea Bachus Kohler" <[EMAIL PROTECTED]>
19) Re:
by Lee Hart <[EMAIL PROTECTED]>
20) Re: Alternative batteries/mower
by Lee Hart <[EMAIL PROTECTED]>
21) Re: Warp 9 / S10 / Zilla Controller
by Lee Hart <[EMAIL PROTECTED]>
22) Re: 8 volt battery - was Re: Help me decide!
by Lee Hart <[EMAIL PROTECTED]>
23) Re: Help me decide!
by Lee Hart <[EMAIL PROTECTED]>
24) Re: Help me decide!
by Lee Hart <[EMAIL PROTECTED]>
25) Re: Help me decide!
by Ryan Stotts <[EMAIL PROTECTED]>
26) Re: e-meter type gadget wish list wanted.
by "STEVE CLUNN" <[EMAIL PROTECTED]>
27) Solectria E-10 manual?
by Jacob <[EMAIL PROTECTED]>
28) RE: Russco vs Zivan vs PFC
by "John G. Lussmyer" <[EMAIL PROTECTED]>
--- Begin Message ---
Rod Hower wrote:
> >>Be able to see Volts and Amps simultaneously.
> EVdash already does this via the Emeter RS-232 comm link.
A lot of new people on the list as of late(That's a good thing.).
Here's the link to EVDash for those interested:
http://www.ohler.com/palm/EVDash.html
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--- Begin Message ---
At 02:20 AM 8/22/2005, you wrote:
Bill Dube wrote:
> This is a 30% to 50% reduction in performance.
Well that puts a completely different perspective on it.. Something
that makes my eyes get big. :)
If you aren't 100% charged on the starting line, your maximum HP
is significantly reduced. The internal resistance of the pack is very
strongly influenced by state of charge and the health of every cell in the
pack.
> bursting batteries at some point.
How does this happen?
There are two ways for it to happen.
1) You discharge one of the cells below 100%. The cell polarity reverses
and it begins absorbing energy instead of producing energy (while you are
drawing lots of current from the pack.) The electrolyte boils and the
battery bursts.
2) You repeatedly over charge a cell (or reverse it mildly several times)
and make it go dry. While drawing lots of current from the pack, the
voltage across this dry cell gets high enough to strike an arc (like ~100
volts). The cell bursts into flames.
Now this series string of deep cycle batteries appears to be a subtly
different beast entirely apparently. Why is that anyways? What's so
different about it?
1) It costs a lot more.
2) There are many cells in different thermal environments getting the same
current.
3) The terminal voltage is a very weak function of an individual cell
voltage and the charger just "runs over" that cell.
4) You care about the A-hr capacity.
_ /| Bill "Wisenheimer" Dube'
\'o.O' <[EMAIL PROTECTED]>
=(___)=
U
Check out the bike -> http://www.KillaCycle.com
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--- Begin Message ---
Here is what I like about the E-Meter:
High Importance
- low cost
- RS232 output
- fuel gauge/percentage of "full"
- settable battery capacity/Peukerts
- great technical support
Medium Importance
- high visibility of user interface in most light conditions
- battery remote temp display
Here is what I do not like about the EMeter
High Importance
- "sleep" mode power consumption is too high
-- very sensitive to installation mistakes
- Ugly user interface (80s style)
- $80 prescaler required for high voltage systems
- poor user guide
Medium Importance
- high voltage is brought into the cabin
- digital meter for instantaneous volts and amps is not too useful - better
to have fake analog
- RS232 not isolated
Things on the "wild side"
- built in GPS
- record all data for downloading after a trip
- keep track of regen
- have a "gauge" which indicates how efficient the person is driving (??)
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 Victor Tikhonov
Sent: August 22, 2005 6:25 PM
To: [email protected]
Subject: e-meter type gadget wish list wanted.
I don't own an e-meter so can't tell what people like or dislike about it. I
know it has RS232 isolation issues, and that's all I know.
Can owners tell me what they don't like about their e-meter, how you'd
rather seeit designed or operated?
Which features are lacking and which you consider redundant?
I'm working on an alternative to an e-meter and am at the point where I can
implement changes most frequently requested.
Basically, could you create a short wish list what do you want such a gadget
to do. Don't let current design bias you - alternative can but doesn't have
to be similar.
Thanks all in advance,
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
This does not sound correct. If the battery pack is isolated from the car
(which is a good thing). When a PFC charger is turned on, the negative side
of the pack is grounded to the case of the charger and connected to the AC
input ground. If the case of the charger is attached to the chassis/body of
the car, then the chassis/body becomes attached to the negative side of the
pack.
When the charger is turned off, the pack is not attached to the ground of
the car.
I have confirmed with Rich that this is the non-isolated behaviour of the
PFC chargers.
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 John G. Lussmyer
Sent: August 22, 2005 6:26 PM
To: [email protected]
Subject: Re: Russco vs Zivan vs PFC
At 06:00 PM 8/22/2005, Ryan Stotts wrote:
>I have the wall and the car and the charger is installed in the car.
>I plug the charger into the wall and now the car is connected to the
>power grid. What would the difference be between an isolated charger
>and a non isolated charger? Because in my mind right now, I don't see
>how either would be any different.
Well, if your Pack is tied to the Car Body, you have a problem.
But since sane people do NOT do that, it's not nearly as severed. A PFC-20
mounted in the car (to the body) will have the AC Ground line connected to
the body.
There IS a connection from a HOT AC line to one end of the pack, but since
your pack isn't connected to the body, it's relatively safe.
It's a nice idea to use a GFCI outlet, which will trigger to show you when
you are getting too much leakage current from your pack....
--
John G. Lussmyer mailto:[EMAIL PROTECTED]
Dragons soar and Tigers prowl while I dream....
http://www.CasaDelGato.com
--- End Message ---
--- Begin Message ---
Christopher Robison wrote:
> Imagine standing on your garage floor in your bare feet. Now imagine
> touching your car. Doing this safely implies that there is no significant
> potential difference between the body of the car and the floor.
Similar to some cars with certain tires and/or seats that cause static
build up and when one stands on the ground and touches the door and
gets shocked?
> By grounding the body of your car, you
> can be assured that it is also zero volts.
Ok, so the charger is now wired to the car body as per the
instructions, so the car body is using that "earth ground/third prong"
in the wall outlet and if there is a voltage leak, it will handle it
and not me when I go to open the door?
Now what is the difference between the current model of "unisolated"
chargers and the model that might be released that is supposedly
isolated? How are the two chargers different? How will they be
installed differently?
> They are MUCH more sensitive, with the idea of preventing electrocution,
> not protecting wiring.
So when I have the charger cranked to be pulling 49 or 50 amps from my
50 amp breaker, am I going to be getting "nuisance trips" because of
the GFCI? Do they even make an outlet for that amperage?
It's been said time and time again on this list "don't work on the
pack while it's being charged". I'll defiantly not work on the car
while it's plugged into the wall.. Like checking to make sure all the
lugs and terminals are tight...
--- End Message ---
--- Begin Message ---
Bill Dube wrote:
> 3) The terminal voltage is a very weak function of an individual cell
> voltage and the charger just "runs over" that cell.
Now *that* is an extremely little known subtle detail that makes all
the difference. I never knew about that. I never imagined that to be
so. But now, it all makes sense. It makes a clear case for needing
to have regs installed.
Thanks for taking the time and effort to clear that up. More
appreciated then words can express.
--- End Message ---
--- Begin Message ---
Hello to All,
Ken Trough wrote:
The Woodburn drags are Sep 4th (Sunday) The John Wayland Invitational
is the Friday before (Sep 2nd) Since one event is Friday night and one
is Sunday, that means we'll be bumming around Portland on Saturday,
most likely. Were probably not going to be the only ones.
Should we try to organize an informal EV get together for Saturday in
Portland?
Yes, it's race time here in Portland...the sun's out, it's hot, and next
weekend's going to be fun!
It starts out with the first annual 'Wayland Invitational' where
everyone with a street legal electric powered drag machine, be it a
bike, a truck, or a car, is invited to join my friends and I at PIR for
some late night 1/4 mile drag racing against the muscle cars, rice
burners, and hot bikes. Sunday it's the terrific Woodburn drags.
Is there anyone local who wants to host a BBQ or something?
I'm way ahead of you, Ken. The next morning after the Friday night
drags, and the subject of this post, is the planned electric breakfast
at the Village Inn restaurant a few blocks from the Wayland home at
102nd & Stark St. Everyone is invited to meet up with us at 9:00 in the
morning, Saturday, for a great breakfast together. Cheryl (not my wife,
another Cheryl) who runs the restaurant, is a big EV fan and is used to
having the likes of father Time, Madman Rudman, Tim Brehm, Marko
Mongillo, and other EVers there all the time. The restaurant has hosted
food gatherings for wayward EVers before, so I thought it only natural
to start a new tradition of a 'day between the races' breakfast meet-up.
She's going to have the billboard displaying something about 'come see
the electric cars', and hopefully, I can convince in-town Woodburn bound
EVers to drag their racing EVs to the restaurant parking lot where we'll
be putting on a little show. So far, it looks like White Zombie, Blue
Meanie, the Heavy Metal Garden Tractor, Fiamp, Goldie, and I'm sure one
of Father Time's machines will be there..the more the better.
I figure Wayland will be busy repairing or re-tuning his rides after
Friday night's runs, so he probably doesn't need a bunch of
distractions at his place.
You are figuring wrong. Even if things go bang the night before, I've
still gotta eat!
Hope to see everyone next weekend!
See Ya....John 'Plasma Boy' Wayland
http://www.plasmaboyracing.com
--- End Message ---
--- Begin Message ---
Don Cameron wrote:
> Things on the "wild side"
> - built in GPS
> - record all data for downloading after a trip
> - keep track of regen
> - have a "gauge" which indicates how efficient the person is driving (??)
In that case, I would like for there to be two models of this new
e-meter. A simple basic version, and the version listed above.
I'm going to buy the $100 model. You can buy the Victor Special $1000 model. ;)
--- End Message ---
--- Begin Message ---
John Wayland wrote:
> at the Village Inn restaurant a few blocks from the Wayland home at
> 102nd & Stark St.
How many outdoor outlets do they have?
--- End Message ---
--- Begin Message ---
Don Cameron wrote:
> If the case of the charger is attached to the chassis/body of
> the car, then the chassis/body becomes attached to the negative side of the
> pack.
Is that what's desired?
> When the charger is turned off, the pack is not attached to the ground of
> the car.
How does that happen when I have the charger hard wired to the body?
--- End Message ---
--- Begin Message ---
> At 06:25 PM 8/22/2005, Victor Tikhonov wrote:
> >Can owners tell me what they don't like about their
> e-meter,
> >how you'd rather seeit designed or operated?
> >
> >Which features are lacking and which you consider
> redundant?
My wish list:
A robust and positive electrical connector not subject to vibration like
the Link 10/E meter set screws.
The ability to drive a conventional analog fuel gage so the uninitiated can
drive the EV.
The ability to be interfaced with the speedometer/odometer pulse signal to
then display miles remaining at current state of charge at current rate of
discharge.
The ability to retain stage of charge info even if the power supply is
interrupted for a short period of time (say less than five minutes).
Remote the display/interface portion from the high voltage portion to
insure isolation and keep high voltage circuits out of the passenger
compartment.
If interface to palm or laptop is included or optional, move up to the more
common USB or perhaps wireless rather than the now obsolete serial port.
An over-ridable low charge cutoff circuit to disable or cutback the
controller of the EV if the battery voltage or state of charge is too low.
Installation safe hookup so reversing a connection only causes it to not
work until corrected rather than causing smoke to escape.
Thanks,
Mike Chancey,
'88 Civic EV
'95 Solectria Force
Kansas City, Missouri
EV List Photo Album at: http://evalbum.com
My Electric Car at: http://www.geocities.com/electric_honda
Mid-America EAA chapter at: http://maeaa.org
Join the EV List at: http://www.madkatz.com/ev/evlist.html
--- End Message ---
--- Begin Message ---
hellow to all you Portlanders :-)
what hotel do you recommend??
others going where are you staying??
Anyone getting into portland airport Fri afternoon
want to share a rental car???
--- John Wayland <[EMAIL PROTECTED]> wrote:
> Hello to All,
>
> Ken Trough wrote:
>
> > The Woodburn drags are Sep 4th (Sunday) The John
> Wayland Invitational
> > is the Friday before (Sep 2nd) Since one event is
> Friday night and one
> > is Sunday, that means we'll be bumming around
> Portland on Saturday,
> > most likely. Were probably not going to be the
> only ones.
> > Should we try to organize an informal EV get
> together for Saturday in
> > Portland?
>
> Yes, it's race time here in Portland...the sun's
> out, it's hot, and next
> weekend's going to be fun!
> It starts out with the first annual 'Wayland
> Invitational' where
> everyone with a street legal electric powered drag
> machine, be it a
> bike, a truck, or a car, is invited to join my
> friends and I at PIR for
> some late night 1/4 mile drag racing against the
> muscle cars, rice
> burners, and hot bikes. Sunday it's the terrific
> Woodburn drags.
>
> > Is there anyone local who wants to host a BBQ or
> something?
>
> I'm way ahead of you, Ken. The next morning after
> the Friday night
> drags, and the subject of this post, is the planned
> electric breakfast
> at the Village Inn restaurant a few blocks from the
> Wayland home at
> 102nd & Stark St. Everyone is invited to meet up
> with us at 9:00 in the
> morning, Saturday, for a great breakfast together.
> Cheryl (not my wife,
> another Cheryl) who runs the restaurant, is a big EV
> fan and is used to
> having the likes of father Time, Madman Rudman, Tim
> Brehm, Marko
> Mongillo, and other EVers there all the time. The
> restaurant has hosted
> food gatherings for wayward EVers before, so I
> thought it only natural
> to start a new tradition of a 'day between the
> races' breakfast meet-up.
> She's going to have the billboard displaying
> something about 'come see
> the electric cars', and hopefully, I can convince
> in-town Woodburn bound
> EVers to drag their racing EVs to the restaurant
> parking lot where we'll
> be putting on a little show. So far, it looks like
> White Zombie, Blue
> Meanie, the Heavy Metal Garden Tractor, Fiamp,
> Goldie, and I'm sure one
> of Father Time's machines will be there..the more
> the better.
>
> > I figure Wayland will be busy repairing or
> re-tuning his rides after
> > Friday night's runs, so he probably doesn't need a
> bunch of
> > distractions at his place.
>
> You are figuring wrong. Even if things go bang the
> night before, I've
> still gotta eat!
>
> Hope to see everyone next weekend!
>
> See Ya....John 'Plasma Boy' Wayland
>
> http://www.plasmaboyracing.com
>
>
>
____________________________________________________
Start your day with Yahoo! - make it your home page
http://www.yahoo.com/r/hs
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--- Begin Message ---
AAAAAARRRGGGGHHHHHHHHH!!!!!!!!
Around each wire is a pulsing magnetic field, induced from the electrical
current in the wire. How much pulsing in the battery wires depends on the
smoothing caused by the wire inductance and the controllers' input capacitors.
On an AC system the pulsing in the battery cables is quite small, due to
the motor having one or more windings being powered all the time, but in a
DC system can be much larger - but I can't quote the magnitude (I actually
have no idea what it'd be in an EV). In an AC system the motor wires seem
come screened as standard.
When you lay the wires together - and preferrably have a slow twist (one
rotation every 18" seems to be about right in industrial applications) the
magnetic fields are of opposite polarity and cancel each other out.
If you don't do anything about the magnetic fields around the traction
cabling, the result can be anywhere from no AM radio reception (usually no
great loss) to an EV that is undriveable due to interference into tacho
sensor circuits etc.
Of course most of the EMI (electromagnetic interference) can be expected to
come from the motor loop wires, but every wire with a changing current will
emit EMI to some extent. It just needs to be kept under control. For
example, getting a 'click' from the stereo when turning on or off the
heater is no big deal.
As for me, I got a piece of screened motor cable (designed for 3-phase
variable-frequency drive use) for my traction wiring, but that's just my
excessive way...
Tape or use sections of glue-lined heatshrink to stop the wires chafing,
and have a fuse in the system of each block of batteries and you should be
OK (not have your EV go up in smoke).
James
--- End Message ---
--- Begin Message ---
Mike Chancey wrote:
> The ability to drive a conventional analog fuel gage
Excellent idea! (one of those "why didn't I think of that!!!" ideas)
Some info on the ohms to move the gauge between full and empty:
http://www.autometer.com/download_instruction/382G.pdf
http://www.autometer.com/download_instruction/421B.pdf
To go along with these new e-meter products, how about a stand alone
product that all it does is be an e-meter type device that drives an
existing fuel gauge?
> The ability to be interfaced with the speedometer/odometer pulse signal to
> then display miles remaining at current state of charge at current rate of
> discharge.
I like it!
> Remote the display/interface portion from the high voltage portion to
> insure isolation and keep high voltage circuits out of the passenger
> compartment.
Excellent.
> If interface to palm or laptop is included or optional, move up to the more
> common USB or perhaps wireless rather than the now obsolete serial port.
Yes, seriously.
--- End Message ---
--- Begin Message ---
Why the tap? Did the screws not want to thread properly in the stock
terminals? Thanks.
Bill Dennis
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Seth Allen
Sent: Monday, August 22, 2005 6:12 PM
To: [email protected]
Subject: Re: Who's Using Marathon NiCads?
If they are like mine, get a squirt bottle for distilled water and some
sharp 10-32 taps.
Seth
On Aug 22, 2005, at 2:29 PM, Bill Dennis wrote:
> I'm putting together a string of 100 right now. Currently I'm in the
> process of talking them out of their packages and cleaning the
> terminals,
> and am building the battery box. I should be to the point of charging
> them
> for the first time in a few weeks. I'll keep you posted. Also, you
> might
> want to join the BB600 board run by John Lussmyer.
>
> Bill Dennis
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
> Behalf Of [EMAIL PROTECTED]
> Sent: Monday, August 22, 2005 11:05 AM
> To: [email protected]
> Subject: Who's Using Marathon NiCads?
>
> Is anyone here using the Marathon NiCad cells? If so, hows it going?
>
> -Sam
>
>
>
--- End Message ---
--- Begin Message ---
James Massey wrote:
> When you lay the wires together - and preferrably have a slow twist (one
> rotation every 18" seems to be about right in industrial applications) the
> magnetic fields are of opposite polarity and cancel each other out.
Is this for AC or DC setups or both?
> Of course most of the EMI (electromagnetic interference) can be expected to
> come from the motor loop wires,
Can I get some sort of shielding sleeve to put those cables in?
--- End Message ---
--- Begin Message ---
Hello everybody:
After lots of thinking, googling and searching, I finally made up my mind.
I found a nice '97 Chevy S-10 (a steal for 1500 Bucks) and will convert it
within the next few month.
I will try to avoid Lead-Acid batteries because I don't like the weight
and the disadvantages.
So - I'd like to talk about the necessary power (in terms of Ah/c3 or Kwh)
needed to get a highway speed range of about 60 Miles. I would think the
S-10 needs about 350 Wh, 400 Wh or maybe 450 Wh to go 60 Mph - or about 4
KW/h to 4.5 KW/h for 10 Miles - so , I am talking about 24 Kw/h to 27 Kw/h
needed to get 60 Miles. I guess that I would have to use some NiCads to
get into that range.
Anybody did an S-10 with Nicads before? Somebody (commercially) willing
and able to provide technology, batteries and charger?
mm.
--- End Message ---
--- Begin Message ---
On 8/22/05, Osmo Sarin wrote:
Hello there,
I´m a newbie from Finland, trying to learn the VERY basics... I thought
Wh = V * Ah, but that´s not the case in this Valence datasheet?
U1:
Wh = 550
V*Ah = 512
Just as 12.8V is nominal, so is the 40Ah rating. Call it engineering vs.
marketing. The units under C/5 testing actually deliver 43 Ah at 23C, hence
the 12.8V x 43Ah = 550 Wh. Since the unit is labeled as a 40Ah module,
12.8V x 40Ah = 512 Wh. Yes, it would have been easier to call the U1 a 43Ah
battery and all the math would have work out. However, offering a 40Ah
(nice round number) means the customer will never be disappointed when the
battery offers more than rated (rare in the battery industry).
Marc Kohler
--- End Message ---
--- Begin Message ---
Chip Sandy wrote:
> Forgive me if this seems like an insane post... I would like to build
> (or preferably buy) an EV... I only make $9.45 an hour and have ZERO
> funds... I live in an apartment, and lack the facilities... classic
> sports car look... companies or organizations who offer sponsorship
> to people who want to do this...
You have no money, you want a sports car, and want someone else to pay
for it? You're right; it is insane. Let us know if you find a way to do
it; there are at least a million others who want to do the same! :-)
I'd start by lowering your expectations. How far is your commute to work
or school? Would an electric bicycle do it? How about an electric
motorcycle? These are cheaper to buy and easier to build, and you can
bring it inside your apartment to store, charge, or work on it.
Moving up to a real car would require the cooperation of your landlord.
You need a place to plug it in, and maybe permission to work on it in
the parking lot.
My first EV only cost about $2000. It was a 1974 Datsun pickup, with a
dozen golf cart batteries in back, a surplus aircraft generator for the
motor, and a home-made charger and controller. It was something a
beginner who is reasonably handy with tools can build.
I built my current EV when I was living in an apartment with no charging
facilities and on-street parking. The total cost was about $5000. I had
to hire people to do most of the mechanical work as I had no place to
work, but was lucky enough to have a friend whose garage I could use to
do some of the work myself.
So it can be done! But you have to substitute a lot of time and
ingenuity for a garage and money.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
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--- Begin Message ---
STEVE CLUNN wrote:
> My Lawn mower project... It looks like the hydraulic drive system
> is wasting a lot of power.
I've been talking to Ernie Parker, an instructor at Hennepin Community
College in Minneapolis. He and his students have built dozens of
hydraulic vehicles. Steve, he would be a good person to talk to to see
if there are any ways to improve your mower's efficiency.
According to him, most of the mass-produced hydraulics have pretty poor
efficiency. Given that they naturally have oil cooling, designers don't
worry much about efficiency.
But when efficiency matters, there are certain units and techniques that
will get you over 90% efficiency, which is competitive with electric
motors. Neon John mentioned a lot of the basics, though in your
prepackaged hydrostatic drive unit there's probably not much that can be
changed.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Lee Hart wrote:
>> Put your money into the most important parts first. I'd say first
>> priority is batteries, then the charger, then instrumentation,
>> the motor, and the controller last.
bo zo wrote:
> I'm kinda in disagerrment with your purchase order... I think Batts
> would be the last to buy, you want them as fresh as possable.
Sorry; I didn't mean that you buy them in this order. Of course you want
to buy a perishable item like batteries last.
I was describing them in the order of importance. What I meant is that
good batteries are the most important part of your EV, so you want to
make sure you get the right ones. Picking the wrong batteries will make
your EV an expensive failure. So it is most important to get them right.
Once you know what batteries you are using, then get the best charger
you can afford. It will pay you pack in longer battery life.
Next, you should pick your instrumentation, so you can tell what is
going on. Without good instrumentation, you are "flying blind" and
almost certain to murder your expensive batteries.
The motor and controller come last, because mistakes here are not likely
to be as serious. You can "get by" pretty well with the wrong motor.
Your EV may be a bit slower or heavier than you like, but it will work.
And you can always sell or trade the motor for a better one without
losing much.
I put the controller last because frankly, there aren't many choices and
they are all "good enough" for a first EV. You may not win any races
with the wrong controller, but your EV will work fine as a daily driver
with any of them.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
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Ryan Stotts wrote:
> Tell me about these newfangled "42-volt" (36 really?)
Correct. What they call "42v" is actually a 36v battery.
I haven't seen any of the batteries they expect to use for this
application. But I suspect they will just be a low amphour capacity
lead-acid battery with 18 cells in.
Now, if they decide to also make the vehicle a hybrid and draw large
peak currents for regenerative braking and/or fast accelleration, they
will need a much larger than normal battery -- something the size and
weight of the Toyota Prius or Honda hybrids. But the auto companies are
such copycats -- I'll bet if they want hybrid-like performance, they
will abandon the "42v" scheme and copy the high-voltage 100+volt hybrids
already offered by Honda and Toyota.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
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Sam Harper wrote:
> I've used motherboards submersed in mineral oil for heat dissipation
> because mineral oil doesn't conduct electricity. Would this work in
> a motor?
The oil wouldn't affect the magnetics, but you'd have to keep it off the
brushes and commutator somehow. Oil in the airgap between rotor and
stator would also add significant amounts of drag at high rpm. So
overall it wouldn't be a good idea.
However, motors often have holes in them to allow the passage of oil or
water for cooling.
>> One option might be to use hydraulic wheel motors.
> But the etek's only $375
That's cheaper than I thought it was.
> (plus the cost of a gear box), and you only have to add the
> controller, not a hydraulic pump capable of turning four of them.
> Nor do you have to have the weight of the hydraulic fluid,
> reservoir, and tubing.
True enough. However, the hydraulic motor needs no gearbox, and includes
the wheel bearings. The hydraulic fluid is also your coolant, and
eliminates any drive shafts, universal joints, etc. The hydraulic pump
to run the motors will cost about as much as the wheel motors, and you
still need the big motor to run it.
So overall, I can't tell which solution works out best in practice. It's
just an idea.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
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>> How about a Lynch, Lemco, or Etek motor and 4QD or Sevcon controller?
>> This should match the efficiency of the expensive AC drives and still
>> cost less.
Peter VanDerWal wrote:
> The Etek is not even in the running, it's at least 5% lower in
> efficiency than the Lynch/Lemco. IIRC the Lynch motor runs at less
> than 90% efficiency when set for neutral timing. I'm not sure how
> efficient the 4QD or Sevcon controllers are, but the motor alone
> is already behind.
These motors are all about 85-90% efficient, battery to shaft. That is
essentially the same as an AC drive, battery to shaft. You have to
remember that the AC drives generally require liquid cooling, and they
leave out the power used for the cooling system. The DC systems are
generally air-cooled, and cooling losses are already included in their
stated efficiency.
Also, the AC drives require an inverter. Most use IGBTs which have a 4-6
volt drop per phase (2-3v per IGBT, 2 in series per phase). The brushed
DC motors can be run straight to the battery with no controller at all,
if you worship efficiency.
And, most AC drives use induction motors, which always lose several more
percent efficiency to slip.
So all I'm saying is that brushed DC motors can have essentially the
same efficiency as an AC drive, if you're willing to spend the same
amount of money.
> Assuming we are doing a full size conversion, like the original
> message, youll need at least 15-20 kw continuous output. Thats
> at least three Sevcon controller $1800, and two Lemco motors $3700,
At least two Lemcos and Sevcon controllers (Sevcon has models big enough
to do it with two, but not one controller).
A better choice would be to get a larger brushed high-efficiency motor.
A scaled-up version of the Lynch motor would be even more efficient.
However, I don't know of one offhand (though they clearly could be
built).
> plus circuit breakers, contactors, etc. Add it all up and youre
> right at the price for a more capable (and more efficient) Siemens
> system.
All these parts have to exist in both systems. No "wins" for AC vs. DC
here.
>> If cost matters more than efficiency, how about any of the sepex
>> motors and controllers now used in golf cars? Or a Curtis 1221R
>> and ADC series motor? Or Zapi H2 controller and Kostov series motor?
> But they don't match the efficiency of the AC drive systems do they?
Why harp on efficiency? Are you building a solar car? I'm thinking more
of practicality. You can build a *practical* EV with either an AC or DC
drive system. Assuming you spend the same amount on each, their
efficiency can be close enough to the same that you can't tell without
careful measurements.
>> Eteks and other PM motors don't have (or need) interpoles because
>> they never run at weak field. The optimum brush position moves
>> because of armature reaction, which occurs with a high armature
>> current and low field strength.
> Hold on a second...this is Lee talking right? Come on Lee, you know
> better. The optimum brush position DOES move on PMDC motors when
> switching from motor to regen. I know this from my own experiments and
> LEMCO has it clearly posted on their website.
{My, are you in a bad mood today :-)
I didn't say armature reaction was zero in a PM motor. I just said they
don't put interpoles on PM motors. This is because armature reaction
isn't big enough to justify interpoles.
But, you can still run a high enough armature current to cause the
optimum brush position to shift. For this reason, they do build PM
motors with advanced, retarded or neutral brush positions depending on
direction of rotation and whether it will be used as a motor and/or
generator.
I suppose if you are trying to eke out that last tiny bit of efficiency,
you could add interpoles or dynamically adjustable brush rigging. But
I've never heard of anyone desperate enough to bother.
>> Traction motors with interpoles are fairly common.
> GE doesn't make traction motors any more.
That would surprise me. I'll have to check. Perhaps with all GE's
financial troubles and merger mania they've sold that division and it's
still operating under another name.
> As far as I know you can't buy an ADC motor with interpoles.
True. They are a low-end supplier.
> I can't find anyone who carries new Kostov motors, are they still
> in business?
Again, they probably do. But I don't know who imports them.
> Who sells Westinghouse motors?
Westinghouse, I suppose.
> Are they available/affordable for the hobbyist?
I'm a hobbyist; I bought 4 of them a few years ago for $500 each.
> And please, you don't serious consider the Jack & Heinz and efficient
> motor do you?
I didn't say it was efficient, but it wasn't designed to be. It is an
aircraft motor, designed for extremely high power-to-weight ratio.
> It doesn't do us any good to point out motors that we, as hobbyists,
> can't buy...
All the examples I gave are readily available to any hobbyist.
> ...or that cost more than better systems (i.e. AC)
The Siemens AC system is about the only affordable AC option for
hobbyists. I applaud Victor Tikhonov offering them for sale. But they
are surplus, too; not current production.
>> I maintain that the efficiency difference between AC and DC systems is
>> largely artificial.
> Come on Lee, can you say "Brushes"? ... as long as motors have
> brushes, they will lag behind brushless AC motors by a couple percent.
The voltage drop of a brush is 1-2 volts. The voltage drop of an IGBT is
2-3 volts. Brushes have *lower* losses than the IGBTs. Why do you think
brushes are so small and have essentially no heating, and IGBTs require
huge heatsinks and elaborate cooling systems? Because they make more
heat!
>> For example, if you budget $2000 for motor and controller, you can
>> get a plain old series motor and PWM controller. Or a plain old 60hz
>> AC induction motor and industrial motor controller. Both will be
>> about 80% efficient, and neither has regen.
> Are you talking used or just small?
Small, new. I was thinking of an ADC 6.7" motor and Curtis 1221C
controller.
> The available low voltage controllers tend to be less efficient
> than the high voltage ones.
The low-voltage controllers use MOSFETs; the high-voltage ones use IGBTs
(both AC and DC). And both have essentially the same efficiency.
> And, of course, any voltage drop across a brush is going to be
> higher than no voltage drop with no brushes (i.e. AC motors).
All motors are AC motors, and all need some kind of switch. All switches
have a voltage drop. The brush of a DC motor is the same as the
transistor in an AC motor. Neither has any intrinsic advantage, and both
can be made arbitrarily small if you are so inclined.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
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Lee wrote:
> And, most AC drives use induction motors, which always lose several more
> percent efficiency to slip.
Reminds me of automatic transmissions(slip). Is it possible to have a
"rotor lock" or stalled rotor situation with an AC motor?
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on all the data logging programs I've seen that the e meter and newer
version use , when using them you can't see what your logging without
stopping the logger watch can't be started once stopped . So if you want to
see what's been recorded while its happening you can't .
----- Original Message -----
From: "Victor Tikhonov" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Monday, August 22, 2005 8:25 PM
Subject: e-meter type gadget wish list wanted.
I don't own an e-meter so can't tell what people like or dislike
about it. I know it has RS232 isolation issues, and that's all I
know.
Can owners tell me what they don't like about their e-meter,
how you'd rather seeit designed or operated?
Which features are lacking and which you consider redundant?
I'm working on an alternative to an e-meter and am at the
point where I can implement changes most frequently requested.
Basically, could you create a short wish list what do you
want such a gadget to do. Don't let current design bias you -
alternative can but doesn't have to be similar.
Thanks all in advance,
--
Victor
'91 ACRX - something different
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Hi all, if any one of you has a Solectria E-10 owners manual, I'd happily
pay you to copy it (including your time) and have it shipped. Thanks
Jacob Harris
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I don't think you quite followed rich's explanation.
I have one of these charges and would be HORRIFIED (as well as DEAD)
to find that's it's case was tied to the pack and the AC line.
One side of the PACK is tied to AC line, NOT the Case of the Charger!
The Case is tied to the Ground wire from the outlet.
At 07:40 PM 8/22/2005, Don Cameron wrote:
This does not sound correct. If the battery pack is isolated from the car
(which is a good thing). When a PFC charger is turned on, the negative side
of the pack is grounded to the case of the charger and connected to the AC
input ground. If the case of the charger is attached to the chassis/body of
the car, then the chassis/body becomes attached to the negative side of the
pack.
When the charger is turned off, the pack is not attached to the ground of
the car.
I have confirmed with Rich that this is the non-isolated behaviour of the
PFC chargers.
--
John G. Lussmyer mailto:[EMAIL PROTECTED]
Dragons soar and Tigers prowl while I dream....
http://www.CasaDelGato.com
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