EV Digest 7028

Topics covered in this issue include:

  1) RE: Battery Terminals need advice!
        by "Mick Abraham" <[EMAIL PROTECTED]>
  2) Electric Cobra is planning to start tour in Mid August (with Luck)
        by "Michael T Kadie" <[EMAIL PROTECTED]>
  3) Re: Questions for those in the-know...
        by "storm connors" <[EMAIL PROTECTED]>
  4) Re: Prius Electronics
        by "(-Phil-)" <[EMAIL PROTECTED]>
  5) Re: Another, fairer comparison
        by "Timothy Balcer" <[EMAIL PROTECTED]>
  6) The flow of current
        by "Phelps" <[EMAIL PROTECTED]>
  7) Re: DC/AC converter (EV to Grid/Home)
        by "(-Phil-)" <[EMAIL PROTECTED]>
  8) Re: Make it
        by "(-Phil-)" <[EMAIL PROTECTED]>
  9) Re: The flow of current
        by "Dmitri" <[EMAIL PROTECTED]>
 10) Re: The flow of current
        by "Roland Wiench" <[EMAIL PROTECTED]>
 11) Re: hey can anyone help me with batteries and construction
        by "(-Phil-)" <[EMAIL PROTECTED]>
 12) Re: CVT (was Manly EV's,  RE: EV are for girls blog)
        by "(-Phil-)" <[EMAIL PROTECTED]>
 13) Re: vroombox and EV ?
        by "(-Phil-)" <[EMAIL PROTECTED]>
 14) Re: VOLTS vs AMPS
        by "(-Phil-)" <[EMAIL PROTECTED]>
 15) Re: Questions for those in the-know...
        by "Joseph T. " <[EMAIL PROTECTED]>
 16) Re: Make it
        by "(-Phil-)" <[EMAIL PROTECTED]>
 17) How to run appliances off your EV pack (was: 12vdc/120vac inverter)
        by "(-Phil-)" <[EMAIL PROTECTED]>
 18) PC, ATX power supply as a DC/DC converter?
        by Michael Barkley <[EMAIL PROTECTED]>
 19) The insanity of rolling your own controller (was: VOLTS vs AMPS & RE: Make 
It)
        by "(-Phil-)" <[EMAIL PROTECTED]>
 20) Re: PC, ATX power supply as a DC/DC converter?
        by "Mark Ward" <[EMAIL PROTECTED]>
 21) Re: Controler
        by "(-Phil-)" <[EMAIL PROTECTED]>
 22) Re: How to run appliances off your EV pack (was: 12vdc/120vac inverter)
        by Bob Bath <[EMAIL PROTECTED]>
--- Begin Message ---
Mark Ward wrote:
>  I was a bit surprised when I ordered some 4/0 battery terminals thinking
> they would be all copper with plating.  They arrived today (24 of them)
and to my surprise the heads themselves are made of lead.
>
> I see this as a problem since they cannot be soldered on and if they are
> overcrimped it might crush the connector part made of plated copper away
> causing a bad connection later.  I also see some potential for the torque
> backing off over time.

Mick says: My favorite lugs have a copper tinned barrel for connection to
the cable, combined with a lead clamp for the fat Ford style barrel posts.
Not all batteries are set up with these type posts but if yours are, they
provide a lot of surface area for the high amp connections to land on.
Contact me off list if you'd like to see a JPEG image of the bi-metallic
lugs, and I can also develop price quotes.

Mick says: If you instead need a lug with an eyelet that you can send a
5/16" bolt through, I also do a bit with these. Copper which is solder
tinned is easiest to find, but the tinned plating eventually dissolves in
the presence of flooded lead acid electrolyte. Some copper lugs are plated
with lead, which is more impervious to sulfuric acid, but the lead plating
is softer and also less conductive initially than a solder tinned lug.

Mick says: With any copper barreled lug, I do a double crimp with some mongo
crimpers which are made for this purpose. Then I heat up a heavy wall
military spec heat shrink tubing that is glue filled. I heat it until the
glue oozes out and am relatively assured then that even air will not enter
the finished connection. I've done post mortems on old cables by cutting
these open and they look pretty good even when the lug itself is all
corroded up and when the rest of the cable looks bad. Soldering into an all
copper lug is OK of course but it's more time consuming and must be done
right with lots of preheat.

Mick says: On a few occasions I've tried to crimp onto lugs with lead
barrels, but the results have not been great. If my crimpers could micro
adjust that would help but invariably one setting is too loose and the next
setting splits the barrel. A hammer style crimper as mentioned by others
might be better for this reason as you can give it just one whack at a time.

Mick Abraham, Proprietor
www.abrahamsolar.com

--- End Message ---
--- Begin Message ---
Well the national electric drag racing finals (August 17-18) are coming up
and I'm going to try and start my cross country tour and starting with a
drive from San Diego to Portland.  It is going to be cutting it close, but
with luck I'm going to make it.   http://ssi-racing.com/tour.asp

So now I'm trying to find / reconnect with people to co-ordinate with, hence
this letter :)

I'm going to keep this generic so that it can be passed on, so that I don't
miss something, and because I'm lazy.

So I'm now looking for people along the way (read you and yours) to help me
set up meetings / presentations for the car, press (I feel I've earned my 15
minutes), affordable lodgings, cruises with other electric cars and cobras
(nice contrast I think) , and of course sponsorship (I have enough money to
pull off the tour, but I'd like to pull it off and give away free tee-shirts
along the way).

Thank you for your support, or insert random rude comment here if you prefer

Michael Kadie
[EMAIL PROTECTED]
619-807-7025

PS in way of self promotion I've put the car up on Discovery Why It's Cool
to try to get it on TV : forum
http://community.discovery.com/eve/forums/a/frm/f/9111927088 - select
electric 65 coupe I encourage people to make comments on my car, as that is
what I can do to help my cause :)

--- End Message ---
--- Begin Message ---
Three phase ac will require deep pockets! :-)  No heater seems an odd
requirement given that they are so easy to do with a ceramic element
replacing the heater core. I guess we could help more if we knew what
you want. How far, how fast, how much $. Bob Bath has step by step CD
on the Honda conversion, but it is for DC not AC.

On 7/15/07, Joshua Cummins <[EMAIL PROTECTED]> wrote:
Hello, the name is Josh and I am service tech for a prominent electric motor
company in the midwest. I have decicded to pool my resources and build my
own electric car. Can anyone point me in the direction of three-phase
inverters, transformers, batteries, photo-cells, control modules and the
like that are being used. Here is the intended setup.

1996 Honda Civic Hatchback
480 volt, three phase motor (0-120hz)
No A/C, NO heater
will use 2 of 5 gears from honda transmission
clutch assy. will be replaced with a static coupling
would also like to incorporate optoelectric cells for recharge
transducer controlled "throttle"

But on a bigger picture, lets collaborate friends, lets start the revolution
thats 40 years late!

_________________________________________________________________
Don't get caught with egg on your face. Play Chicktionary!
http://club.live.com/chicktionary.aspx?icid=chick_hotmailtextlink2




--
http://www.austinev.org/evalbum/1059

--- End Message ---
--- Begin Message --- Get the Denso compressor, but leave the electronics alone. Order yourself a 240v 3-phase VFD of suitable amperage off of ebay. Much easier to hack!

I've studied the torn-apart Prius inverter, it would be a monumental reverse-engineering job just to get that part working.

It shares the board with the 200v to 500v DC/DC converter and the 200v to 12v as well. Lots of stuff, and custom IC's!

Here's the best link I could find:
http://www.techonline.com/product/underthehood/199501618

Definitely interesting reading for all the curious techies!

-Phil
----- Original Message ----- From: "Jeff Shanab" <[EMAIL PROTECTED]>
To: "Electric Vehicle Discussion List" <ev@listproc.sjsu.edu>
Sent: Sunday, July 08, 2007 9:45 AM
Subject: Prius Electronics


I am wanting to put A/C in my EV.
I have decided that the 2nd gen prius system is the way to go. It runs
off of the pack the motor sees 201.6V 3phase AC and is buried in the
inverter.
I wanted to know if I could extract that part of the inverter out and if
it will run on the 288V pack I have.

I found this:
http://www.techno-fandom.org/~hobbit/cars/ginv/index.html

Others may find this interesting to. I really like the way these(and
ford, and brusa) implement their water cooling.



--- End Message ---
--- Begin Message ---
Let me just respond to a few things.. I'll stay away from Nukes and
climate change :)

First, distributed power systems and incentives for renewables and
solar would go a heck of a long way towards reducing demands on the
grid anywhere, including CA. Germany has demonstrated great leadership
in this area and is proving that solar is not only viable, it is
profitable. Of course, it isn't profitable for a few wealthy
concerns.. which is why the large concerns dismiss their results and
bad talk the idea of incentives. I'm just glad I live in a state that
reimburses 50% of wind and solar installations. Once we get clear of
our debt, we're putting in a combination setup that should make us
almost entirely energy independent. That's a darn good feeling :)

Secondly, there are a lot of reports that talk about peak and non peak
capacity, some weighing in one direction, some in the other. What I
think it comes down to simply is that there is spare capacity in much
of the country (if not all of it), and that can be used at night to
charge up EVs. As far as pollution goes, you would have less pollution
since it can be controlled more easily at plants than out of a million
tailpipes. Either way, emissions would be reduced overall, and energy
use would be reduced. That valuable fuel could be used for heavy
transport, plastics, and other more important uses than getting me to
the grocery store.

I don't think any of us disagree that EVs are a good idea.. why would
we be here then? Ultimately, I believe it is more important to simply
acknowledge that there are many more ways than one to get the same
goals accomplished, and if we just keep open our diversity, we'll find
a middle ground and come up with a balanced solution that everyone can
be happy or ticked off with equally. ;-)

--T

--- End Message ---
--- Begin Message ---
If my motor is rated for 300 amps at 30 volts..

If I increase the voltage ..To 36 volts will the amount of amps that it uses
decrease as the voltage increases..

Or will the amps remain constant?

Thanks Mitchell

--- End Message ---
--- Begin Message --- You just need an H-bridge of MOSFETs driven by a relatively simple 60hz (240hz / 4) circuit to get "modified sine" output. (or driven much faster to get a more pure sine via PWM) Crack open any modern 12V DC to 120v AC inverter, you'll see 2 stages, the first is a boost converter that takes 12V DC to around 140V DC, then a second H-bridge stage that takes the DC back into AC. You could either hack an inverter of the required capacity by directly injecting the DC, or just copy their 2nd stage design and scale it up.

It's also relatively easy to do with a microcontroller and an output stage. The low frequencies involved (for modified sine) makes the MOSFET drive circuitry much more forgiving.

There are some high-performance MOSFETs on the market now, so it should be possible to make a compact box to do this with a low component count.

-Phil
----- Original Message ----- From: "Jim, Saturn Guy" <[EMAIL PROTECTED]>
To: "EVlist" <ev@listproc.sjsu.edu>
Sent: Saturday, June 23, 2007 6:33 PM
Subject: DC/AC converter (EV to Grid/Home)


Hello all. I just joined the list and have spent hours reading through some of the archives. I would like to pick your brains a bit and ask if anyone has built a DC/AC converter for an Electric Vehicle. I converted a 94 Saturn SL1 and have been driving it since January of this year. I would like to build an on-board DC/AC converter that runs off the 126 volt pack of my EV and puts out 110v ac to run vital parts of the house in the event of power outage. All that energy stored and only have it for the EV feels limited. So, has anyone built or bought one? I've found nothing out there as of yet, but the web feels almost as vast as space its self. If you don't have a specific spot you're aiming for, you could be out there wandering aimlessly for ever. Thank you to whom ever reads this post. I know all of your time is important and I do appreciate it.

 Thank you
 Jim Dawson


---------------------------------
No need to miss a message. Get email on-the-go
with Yahoo! Mail for Mobile. Get started.

--- End Message ---
--- Begin Message --- The difference is the amount of power it must handle. I've built many small motor controllers, and found it relatively easy to design controllers to handle low power levels. When you get to the level needed to handle EV amperage, the engineering gets much more critical and difficult. Almost always you end up blowing up a lot of power stages before you get your design right, and they are costly!

-Phil
----- Original Message ----- From: "Rob Hogenmiller" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Saturday, June 23, 2007 7:59 PM
Subject: Re: Make it


I've been checking out these speed controllers for electric vehicles. I'm somewhat dissapointed in what I've come across. When I raced shifterkarts we had speed controllers for our vehicles we could select A, B, C, or D programs each setting could be programmed on a computer to deliver different types of power curves.

http://www.swedetechracingengines.com/parts_accessories/pictures/spi_548x480-047c.jpg

I think they were around $250

I have messaged the gentleman that makes them to see if he would have interest in building them for EV's.

God bless


----- Original Message ----- From: "Phil Marino" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Saturday, June 23, 2007 12:20 PM
Subject: RE: Make it





From: "Phelps" <[EMAIL PROTECTED]>
Reply-To: ev@listproc.sjsu.edu
To: <ev@listproc.sjsu.edu>
Subject: Make it
Date: Sat, 23 Jun 2007 13:00:11 -0400 (Eastern Daylight Time)


Seeing how a controller is only a on off switch that has a frequency that
varries .. The faster it goes the faster you go ..

I am sure this can be reproduced without spending 700 bucks..

The question I need to know is at what rate dose the average controllers on
and off frequency change to and from.
In time sec .and How many time in a sec . To archive O to max speed

Most controllers ( the Curtis C series is an exception) use a constant switching frequency. The duty cycle ( % of the time that the "switch" is closed) is varied to control the power to the motor. That is what controls how fast you go.

Switching hundreds of amps at hundreds of volts reliably may be more difficult ( and expensive) than you think.

If you succeed at building a good controller for less than $700, please let us know.

Phil Marino



Mitchell


_________________________________________________________________
PC Magazine's 2007 editors' choice for best Web mail-award-winning Windows Live Hotmail. http://imagine-windowslive.com/hotmail/?locale=en-us&ocid=TXT_TAGHM_migration_HM_mini_pcmag_0507





--- End Message ---
--- Begin Message ---
It will increase, but it can be controlled with a controller.

----- Original Message ----- From: "Phelps" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Sunday, July 15, 2007 1:03 PM
Subject: The flow of current



If my motor is rated for 300 amps at 30 volts..

If I increase the voltage ..To 36 volts will the amount of amps that it uses
decrease as the voltage increases..

Or will the amps remain constant?

Thanks Mitchell


--- End Message ---
--- Begin Message ---
Hello Phelps,

Motors are inductive loads, where the ampere will rise with increase voltage 
unlike resistance loads as a heater, where if you have a 240 v heater 
element at 8 amps, it will become 4 amps at 120 v.

A motor that it windings are rated for 240 v may use 10 amps where A motor 
has its windings rated for 120 V may use 20 amps for the same hp.  But using 
different voltages on the same windings rated for some other voltage the 
ampere may increase as follows:

Here is the results of a 180 VDC motor test I did using different voltages 
at no load:

Battery Pack    Actual Volts    Amperes      Rpm

12                 12.6            5         634
18                 18.9            6        1013
24                 25.4            6.2      1390
30                 31.8            6.4      1773
36                 37.8            6.6      2143
42                 44.5            6.8      2521
48                 51.2            7.0      2985
54                 57.5            7.5      3270
60                 63.7            8        3715

There is a maximum voltage and ampere rating you can go over on a motor. 
This is call the Service Factor (SF).  If 115V motor has a rated SF of 115% 
and the motor has a ampere rating of 200 ampere for continuous running, then 
200A x 1.15 = 230 amps.  The 115V motor can run on 115V x 1.15 = 132.25 V.

On the label for the motor,  there should be a Service Factor which may say 
SF 1.25 for a DC motor.  I don't why the ADC and Warp motors do not have 
motor label that list the specifications of the motor.

My General Electric motor does.  It list the DC motor as 165 volts at 175 
amps at 32 HP with a SF of 1.25 meaning the over voltage can be about 208 
volts and the over ampere can be 218 amperes continuous.

Roland





----- Original Message ----- 
From: "Phelps" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Sunday, July 15, 2007 11:03 AM
Subject: The flow of current


>
> If my motor is rated for 300 amps at 30 volts..
>
> If I increase the voltage ..To 36 volts will the amount of amps that it 
> uses
> decrease as the voltage increases..
>
> Or will the amps remain constant?
>
> Thanks Mitchell
>
> 

--- End Message ---
--- Begin Message ---
I'll stab at a few:

1 horsepower = 745.699 watts

Of course in a Generator, there are efficiency losses, so typically you will see a 20kw engine powering a 15kw gen head.

Regenerative braking (aka "regen") is recovery of the vehicles rolling energy instead of wasting it. It usually involves a more complex control system. It basically turns the motor into a generator briefly when you are wanting to slow down, and charges the battery instead of just discarding this energy as heat in the brake linings.

You cannot charge anything from your vehicle that doesn't cost you at least that much energy going in. An attempt as such is labeled "over unity" or "perpetual motion" because it violates the first law of thermodynamics. See:
http://en.wikipedia.org/wiki/Conservation_of_energy
also:
http://en.wikipedia.org/wiki/Perpetual_motion

Note that discussion of anything along these lines is prohibited on this discussion list. So don't ask any more about it. There is plenty of information on the web about it and why it won't work. If it did, we'd never have to worry about energy ever again, and range would be a non-issue.

Building controllers is a very complex and difficult thing. Any attempt at building a PWM controller for EV use will likely cost you more in the end then buying one. Trust me, I have done it!

If you have a lot of years of experience in electrical engineering, it will still cost your ass, (don't ask how I know), so any attempt by someone without these years of experience will almost without exception be a disaster. Don't even try. Best bet is to spend your effort in other areas and buy a good controller or if you can't just go "old style" with a contactor controller, or even a block of wood with nails in it. =)

-Phil
----- Original Message ----- From: "gulabrao ingle" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Sunday, June 24, 2007 9:11 AM
Subject: hey can anyone help me with batteries and construction


Hi,

I recently joined the list 2 days ago,
Well i am planning a conversion of my own here in Mumbai, India
I am looking for a car in my budget in and around Mumbai,
I have shortlisted a few candidates for the conversion,

I have a few questions and clarifications I would like to ask before I
actually jump into the conversion, anyone can reply to me on my email
personally or through the list( if the question sound unrelated to this EV
topic discussion list)

1. what is the minimum amount of horse power is required to run a 15 kw
generator ?
2. which batteries are better, 10 12volt lead acid or 20 6v lead acid for
range ?
3. does motor size and power rating affect the range of an full electric
vehicle ?
4. what voltage and current rating of motor should i look for a vehicle of
gross weight of 900 kgs to go 100 km
5. should i try rebuilding certain parts of the vehicle in fibreglass , what
implications will it have ?
6. what specification of controller should i look for this project ? (hey
anyone in India on this list have a working controller or can help me get a
controller)
7. what is regenrative braking , how does it work and what mechanisms have
to be there to put it in to my car.?
8. can alternators connected to the 4 wheels and motor of my car produce
enough juice to charge a second set of lead acids while i am driving ?
9. where can I get kits for the controller ? is it possible to get them ,
either import or get them somehow in Mumbai ?
10. what kind of batteries are best for getting the maximum range apart from li-ion and li polymer ? and what is their cost and price ? which is the best
deal overall for say a range of 100 miles with speeds over    100 kmph ?
11. do I need to do some modifications on the electronics level to get the
most range from my setup ?

I hope you answer some of these questions and do not ignore this mail like
my last post.

Thanks
Gulabrao

I could really appreciate if I can find some local help and guidance through
this list or a mentor whom I can rely upon.


--- End Message ---
--- Begin Message --- Some of the earlier (before PWM) electric golf carts used a snowmobile-style variable pulley belt-drive CVT. With PWM, these have pretty much disappeared because they have high losses. (friction)

-Phil
----- Original Message ----- From: "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Sunday, June 24, 2007 12:50 PM
Subject: CVT (was Manly EV's, RE: EV are for girls blog)


On 24 Jun 2007 at 9:26, Loni wrote:

Has even one person here tried [CVT] yet? Anybody?

This is kind of vague, but here goes.

I know of at least one Formula Lightning racer which tried it some years
back.  They used a Honda transaxle, IIRC.  No idea what the results were.

At least one person in CA also was doing some work with CVTs in EVs in
the 1980s.  I could probably find his name if I went back through my old
issues of Current EVents, but that would take more time than I have free at
the moment, sorry.  Maybe one of the west coast old-timers will remember
who it was, and how it worked out.

My view is that the torque band of most motors is so much wider than an ICE
that the higher losses in a CVT result in a net loss over a conventional
transmission.  Seems to me that most motors really need only 2-3 ratios to
be happy.  I'm not an engineer, though.

David Roden
EVDL Administrator
http://www.evdl.org/



--- End Message ---
--- Begin Message --- Yes, all you'd probably have to do is output a tach and vacuum signal. The tach signal is easy if you already have an encoder. Then I imagine connecting the manifold vacuum input to a current shunt instead would achieve a similar result.

It might be a better idea to connect the tach input to a pot-controlled frequency generator so you can manually "goose it" at lights and such.

If someone sends me one, I'll make an add-on microcontroller board that provides the right inputs to make it work. =)

-Phil
----- Original Message ----- From: "Florian Schmidt" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Sunday, June 24, 2007 2:17 PM
Subject: vroombox and EV ?


Thinking about the pedestrians that don´t hear an EV coming, i was wondering if it´s possible to install the vroombox in an EV.

What do you think ?

http://www.vroombox.com/vroombox/
--
Psssst! Schon vom neuen GMX MultiMessenger gehört?
Der kanns mit allen: http://www.gmx.net/de/go/multimessenger



--- End Message ---
--- Begin Message ---
No, neither by itself means anything.

"Real world" power is Watts.  746 of them is a horsepower.

Amps X volts = watts.  It's that simple.

A given motor will usually turn faster with more volts, and need more amps when more load is placed on it.

A vehicle with 100 volts using 100 amps is just as powerful and fast as a vehicle using 1000 volts and only 10 amps. It's the limitations of battery technology and control electronics that cause us to seek a compromise.

-Phil
----- Original Message ----- From: "Rob Hogenmiller" <[EMAIL PROTECTED]>
To: "EV Discussion" <ev@listproc.sjsu.edu>
Sent: Sunday, June 24, 2007 7:23 PM
Subject: VOLTS vs AMPS


So far I've come to the conclusion that VOLTS is the major power contributor, the higher the VOLTS the more power the motor can make the vehicle go.

AMPS seem to be how long the vehicle can go, the more AMPS the batteries have the longer the vehicle can drive before being charged.

There also seems to be some correlation with the AMPS in regards to power.

Does anyone have any quick comments or suggestive reading.

God bless


--- End Message ---
--- Begin Message ---
   Metricmind.com is a website that sells AC components. But be
warned, AC is very expensive. Also, I'm not sure you can fit enough
batteries into your Civic to make 480 volts. Lithium based batteries
may be needed if you want to have 480 volts.

On 7/15/07, storm connors <[EMAIL PROTECTED]> wrote:
Three phase ac will require deep pockets! :-)  No heater seems an odd
requirement given that they are so easy to do with a ceramic element
replacing the heater core. I guess we could help more if we knew what
you want. How far, how fast, how much $. Bob Bath has step by step CD
on the Honda conversion, but it is for DC not AC.

On 7/15/07, Joshua Cummins <[EMAIL PROTECTED]> wrote:
> Hello, the name is Josh and I am service tech for a prominent electric motor
> company in the midwest. I have decicded to pool my resources and build my
> own electric car. Can anyone point me in the direction of three-phase
> inverters, transformers, batteries, photo-cells, control modules and the
> like that are being used. Here is the intended setup.
>
> 1996 Honda Civic Hatchback
> 480 volt, three phase motor (0-120hz)
> No A/C, NO heater
> will use 2 of 5 gears from honda transmission
> clutch assy. will be replaced with a static coupling
> would also like to incorporate optoelectric cells for recharge
> transducer controlled "throttle"
>
> But on a bigger picture, lets collaborate friends, lets start the revolution
> thats 40 years late!
>
> _________________________________________________________________
> Don't get caught with egg on your face. Play Chicktionary!
> http://club.live.com/chicktionary.aspx?icid=chick_hotmailtextlink2
>
>


--
http://www.austinev.org/evalbum/1059



--- End Message ---
--- Begin Message --- You can't regen into a fully charged pack. (or rather, you shouldn't!) The sevcon my be aborting regen because it sees the pack is fully charged. Try running it down a bit first.

Regen will be more effective at higher speeds. At a crawl it will not do much of anything. It cannot be used to "hold" the vehicle on a hill, as the motor must be moving to generate anything.

You may be geared too tall for effective low-speed regen. If you want to do a lot of city driving, gear your final drive lower. Your performance will be much better, and regen will be more effective and continue to brake at lower vehicle speeds.

-Phil
----- Original Message ----- From: "Garret Maki" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Monday, June 25, 2007 6:39 AM
Subject: RE: Make it


Has anyone else used regen on a Sevcon Millipak Perm. Mag. Controller?

I have an electric motorcycle with an Etek motor and Sevcon Millipak
controller with variable regen.  It is only providing slight slowing,
not any serious braking power.
So far I have just tried back and forth in front of my house, with a
nearly fully charged pack.  I do see the pack voltage go up a volt or
two under regen braking.  At 30 MPH I can clearly tell it is adding some
drag, coming to a stop it rolls easily with regen brake fully engaged.
I have the braking set to 100% on the controller.

I am thinking I am missing something, because the amount of braking I am
getting doesn't seem to agree with accounts of other people with other
systems hardly needing to use the mechanical brakes.

Anyone else have experience with this controller for regen?

-Garret Maki
Boulder Colorado



--- End Message ---
--- Begin Message --- No, I'm not suggesting you use 12v to power it. This would be double-conversion in any event.

You crack open the inverter and inject your pack voltage after the first DC-DC boost stage.

It's easy to calculate the load at 12v.  Amps X volts = Watts.

3000 Watts divided by 12 volts is 250 amps. This is not including efficiency losses. It'll likely be around 270A for a cheap inverter.

There are no EV DC-DC converters that will get anywhere close to this.

The other option is to run your loads directly off the DC pack voltage. Many modern AC loads will also with DC directly:
Computers, both Laptops and desktops
TV sets (more modern ones)
Electric heaters (without fan motors!)
Compact Fluorescent lamps
Incandescent lamps
Inverter driven Microwave ovens

Just about anything WITHOUT a iron-core in it somewhere is generally ok. This means all of these are a no-no on DC:
heavy wall-wart powered stuff (light ones like laptops use are ok)
AC motors
refrigeration equipment
Air compressors
Small things like Clock-radios (usually contain a transformer)

Things that might be OK with motors are those things with brushed motors, such as an angle grinder or many vacuum cleaners, etc.

If you wish to experiment, buy a glass fuse assortment and make up a little cable with an in-line fuse holder and standard outlet on the end. Look at the nameplate of the appliance, choose a fuse close to the amperage rating and install it in the fuseholder. This is for safety. (Disclaimer: Running devices designed for AC on DC can be unsafe for the device, yourself, and the surrounding environment!) Plug the appliance in. If it doesn't work, or work correctly, try reversing the polarity quickly. If it still doesn't work, unplug it right away to avoid possible damage. If it does appear to work, then test all the functions, if it appears to be normal you can add it to your list. Note that some power supplies will not start correctly on one polarity, so try both.

Make sure nothing gets hot when run for a bit. I've run many compact fluorescent lights, computers, TV sets, etc, off of a 144v volt pack successfully.

If you find you can run most of your load this way, then you may be able to get by with a small inverter off your 12v system for the few things which don't like DC.


-Phil
----- Original Message ----- From: "Bill & Nancy" <[EMAIL PROTECTED]>
To: "(-Phil-)" <[EMAIL PROTECTED]>
Sent: Sunday, July 15, 2007 11:47 AM
Subject: 12vdc/120vac inverter


Hi Phil,
I have been looking at this situation myelf. I was looking for a 3000 watt inverter and found several using the above search words. I found some staring at around $400 to $2000. Most sites don't list the amperage pull on the 12volt battery. One site listed the amperage draw on their unit as 192 amps. The dc/dc for most ev's only put out 30-45 amps, so the battery would be unable to hold it's charge nore than an hour. Let me know if you figure a way around this limitation.
Bill


--- End Message ---
--- Begin Message ---
Wow, you think I could use a simple ATX-PC power
supply with my battery pack, and use the 12 volts out
for my accessories?  Never thought about doing that,
off to see if I can keep from blowing up some power
supplies..... Cause I really need a DC/DC converter
for my headlights.

> The other option is to run your loads directly off
> the DC pack voltage. 
> Many modern AC loads will also with DC directly:
> Computers, both Laptops and desktops
> TV sets (more modern ones)
> Electric heaters (without fan motors!)
> Compact Fluorescent lamps
> Incandescent lamps
> Inverter driven Microwave ovens
> 




M. Barkley
   
  www.texomaev.com
   
  http://www.austinev.org/evalbum/1135

--- End Message ---
--- Begin Message --- The Caps are Low ESR. Put those crappy ones in there and they won't last long, nor will your 36 BUZ30A's and gate drive transistors!

Keep in mind you gotta pay for the engineering. Even if you yourself tear apart a Curtis and copy it, your time is worth something, isn't it? I am an experienced reverse-engineer and I do contract reverse engineering often to make a living. I'm guessing it would take me at least a week to reverse-engineer a Curtis fully from scratch and begin laying out a PCB. I've repaired several so far, and had to do a moderate amount of RE already for that reason, as Curtis doesn't share schematics.

If I'm making a measly $25 an hour like McDonalds managers do, that week is still about $1000, and I still haven't even ordered the parts!

Oh, and this is for copying a lowly Curtis with it's 20 year old design! Why would I want to do that? =)

-Phil
----- Original Message ----- From: "Ian Hooper" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Monday, June 25, 2007 10:00 AM
Subject: Re: VOLTS vs AMPS & RE: Make It


OK, I wasn't picking on their component choice so much as saying you can build your own speed controller for a lot less than it costs to *buy* a Curtis. The retail price of the 1221s is about $1100, correct? For power stage component cost, going on quantities of 1000 units, prices from digikey are:

32x 220uF 200VDC electro caps @ $0.87ea = $27.84

36x BUZ30A @ $1.13ea = $40.68

12x 300V 60A diodes @ $1.08ea = $12.96 (couldn't find SR4180R-C, this is actually the higher-rated STTH60P03SWs)

TOTAL = $81.48

So, $1100 seems a bit much to me. I realise these three components aren't the only expense, but still..

As for component selection, they're fine I guess but I tend to think it's more elegant to go with a smaller number of higher-rated semis, such as the IXFK120N20 (200V 120A 0.017ohm MOSFET) @ ~$10ea or the STTH60L06C 80A diodes @ ~$2ea, even though it may end up costing a tad more.

-Ian

On 25/06/2007, at 10:10 PM, Lee Hart wrote:

Ian Hooper wrote:
Out of interest, I'm building a motor speed controller at present and I will have to agree that it can be done quite a lot cheaper than the price of the Curtis units. They are a 20 year old design now, and semiconductor technology (both transistors and microcontrollers) has improved quite a lot in the last few decades. e.g you can now get individual MOSFETs with about 1/10th the on-resistance of those used in the Curtis controllers.

Really? A Curtis 1221 controller's power section has 32 220uf 200vdc electrolytic capacitors, 36 BUZ30A 200v 21a 0.1 ohm MOSFETs, and 12 200v 40a SR4180R-C diodes. Look up the prices, and add up the cost. Now tell me what you would use in their place that's any cheaper.

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in    --    Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377,  leeahart_at_earthlink.net





--- End Message ---
--- Begin Message --- A pc power supply requires modifications to make it put out 13.8 volts. It can be done and there are numerous articles on how to do this. If you don't, your lights and wipers and other accessories will bog down due to voltage drops in your system. 12v will not recharge your battery on your EV either if you are using one.

Mark Ward
95 Saab 900SE "Saabrina"
www.saabrina.blogspot.com


----- Original Message ----- From: "Michael Barkley" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Sunday, July 15, 2007 2:45 PM
Subject: PC, ATX power supply as a DC/DC converter?


Wow, you think I could use a simple ATX-PC power
supply with my battery pack, and use the 12 volts out
for my accessories?  Never thought about doing that,
off to see if I can keep from blowing up some power
supplies..... Cause I really need a DC/DC converter
for my headlights.

The other option is to run your loads directly off
the DC pack voltage.
Many modern AC loads will also with DC directly:
Computers, both Laptops and desktops
TV sets (more modern ones)
Electric heaters (without fan motors!)
Compact Fluorescent lamps
Incandescent lamps
Inverter driven Microwave ovens





M. Barkley

 www.texomaev.com

 http://www.austinev.org/evalbum/1135


--- End Message ---
--- Begin Message ---
They do, all the time!  Ask around...

The general reason they don't is because they are not switching any high voltages. If the brush timing is correct, and the current is balanced between the armature and field, then there is very little potential difference between the adjacent spots on the commutator when the brushes cross.

If you open a large AC switch, you'll notice that some of the time there is a big arc, and other times there is little or no arc. This is because some of the time you happen to open the switch when the AC waveform is near zero crossing, and other times when it's not. The AC has the beauty of crossing zero 120 times a second, so switch arcs usually only last that long before self-extinguishing for lack of current.

-Phil
----- Original Message ----- From: "Phelps" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Monday, June 25, 2007 5:31 PM
Subject: Re: Controler


Ok .. I got a stupid question.. I got the welder point a few times now and
have been thinking about it .. Why don't out eclectic motors brushes weld
and melt when we run our E Vs??/

And what ever the reason is that they don't.. Why can not that be the same
kind of contact for a switch?
Mitchell

-------Original Message-------
From: Andre' Blanchard
Date: 06/25/07 19:43:30
To: ev@listproc.sjsu.edu
Subject: Re: Controler

At 05:17 PM 6/25/2007, you wrote:
If you want to build a mechanically driven drum switch circuits for motor
controller, it is best to get a early addition copy of The Standard
Handbook
for Electrical Engineers from the year 1933 or so.

You will not be able to down load this handbook, but you may luck out and
get a copy from the public library. The new later handbooks will set you
back more than a cost of a controller and they are not that detail.

It has complete design section on any type of controller you want to build.

There even sections on how to different type of batteries are made, how
motors are made and different winding configurations.

With this handbook, all you need is a shop with machine tools, the raw
material, and it will show you how in detail to design and build any
electronic and electrical systems.

Roland

I did not find the entire books but I did find part of it.

Section 13 from the Standard Handbook for Electrical Engineers 1908
http://books.google.com/books?id=tkAFAAAAMAAJ

Some other books
http://books.google.com/books?id=SsIJAAAAIAAJ
http://books.google.com/books?id=UOjpsFsWSrAC
http://books.google.com/books?id=iDASAAAAIAAJ
http://books.google.com/books?id=cgsAAAAAMAAJ
http://books.google.com/books?id=UP8HAAAAMAAJ
http://books.google.com/books?id=P_m7webHng8C
http://books.google.com/books?id=5WGfE9UR_AEC
http://books.google.com/books?id=ZlCLIxkECvwC

__________
Andre' B. Clear Lake, Wi.





--- End Message ---
--- Begin Message ---
Guys, it's remarkable you're checking into this right
now, as I was just doing the same thing this week.

Obviously, the higher the voltage, the lower the
current draw.  Thus l would _love_ an inverter that
went up to the voltage of my pack, 144V, and could
pull 6A to power my fridge, plus another few amps for
lights, fans, etc. in a rolling blackout or brownout
event.

Xantrex: ProSine model up to 24V, yields 1800W.  Would
be around $1800-2500 IIRC.

Dear Mr. Bath,
 
Thank you for contacting Solatron Technologies for
your power inverting needs.  I spoke to our Technical
Manager regarding your desire to power the home with
the electric car battery during utility power outages.
 He stated that although this is possible if you are
able to rewire the 144 volt electric car battery to a
48 volt system, if the power outages are frequent or
long lasting, he would recommend a separate battery
bank altogether.
 
A separate battery bank would allow for charging via
an inverter and the utility grid power.  Once the
utility power was down, the inverter system would pull
power back from the batteries directly to a sub panel
dedicated to the emergency loads only. 
 
If you can confirm the size/type batteries being used
on the electric car and that they can be rewired to a
48 volt system, we can make a recommendation on a
complete inverter system.  Most likely, you would want
to utilize the Xantrex SW5548 inverter, which is
priced at $2,750.
 
I look forward to hearing back from you.
 
Sincerely,
 
Diana Howell

PV Powered: Uses the grid to get what the sine wave
"looks" like.  Thus, it is useless in this
application.

Outback: Still waiting to hear from.

Hope that helps, 

--- "(-Phil-)" <[EMAIL PROTECTED]> wrote:

> No, I'm not suggesting you use 12v to power it. 
> This would be 
> double-conversion in any event.
> 
> You crack open the inverter and inject your pack
> voltage after the first 
> DC-DC boost stage.
> 
> It's easy to calculate the load at 12v.  Amps X
> volts = Watts.
> 
> 3000 Watts divided by 12 volts is 250 amps.  This is
> not including 
> efficiency losses.  It'll likely be around 270A for
> a cheap inverter.
> 
> There are no EV DC-DC converters that will get
> anywhere close to this.
> 
> The other option is to run your loads directly off
> the DC pack voltage. 
> Many modern AC loads will also with DC directly:
> Computers, both Laptops and desktops
> TV sets (more modern ones)
> Electric heaters (without fan motors!)
> Compact Fluorescent lamps
> Incandescent lamps
> Inverter driven Microwave ovens
> 
> Just about anything WITHOUT a iron-core in it
> somewhere is generally ok. 
> This means all of these are a no-no on DC:
> heavy wall-wart powered stuff (light ones like
> laptops use are ok)
> AC motors
> refrigeration equipment
> Air compressors
> Small things like Clock-radios (usually contain a
> transformer)
> 
> Things that might be OK with motors are those things
> with brushed motors, 
> such as an angle grinder or many vacuum cleaners,
> etc.
> 
> If you wish to experiment, buy a glass fuse
> assortment and make up a little 
> cable with an in-line fuse holder and standard
> outlet on the end.  Look at 
> the nameplate of the appliance, choose a fuse close
> to the amperage rating 
> and install it in the fuseholder.  This is for
> safety.  (Disclaimer: Running 
> devices designed for AC on DC can be unsafe for the
> device, yourself, and 
> the surrounding environment!)  Plug the appliance
> in.  If it doesn't work, 
> or work correctly, try reversing the polarity
> quickly.  If it still doesn't 
> work, unplug it right away to avoid possible damage.
>  If it does appear to 
> work, then test all the functions, if it appears to
> be normal you can add it 
> to your list.  Note that some power supplies will
> not start correctly on one 
> polarity, so try both.
> 
> Make sure nothing gets hot when run for a bit.  I've
> run many compact 
> fluorescent lights, computers, TV sets, etc, off of
> a 144v volt pack 
> successfully.
> 
> If you find you can run most of your load this way,
> then you may be able to 
> get by with a small inverter off your 12v system for
> the few things which 
> don't like DC.
> 
> 
> -Phil
> ----- Original Message ----- 
> From: "Bill & Nancy" <[EMAIL PROTECTED]>
> To: "(-Phil-)" <[EMAIL PROTECTED]>
> Sent: Sunday, July 15, 2007 11:47 AM
> Subject: 12vdc/120vac inverter
> 
> 
> > Hi Phil,
> > I have been looking at this situation myelf. I was
> looking for a 3000 watt 
> > inverter and found several using the above search
> words. I found some 
> > staring at around $400 to $2000.
> > Most sites don't list the amperage pull on the
> 12volt battery. One site 
> > listed the amperage draw on their unit as 192
> amps. The dc/dc for most 
> > ev's only put out 30-45 amps, so the battery would
> be unable to hold it's 
> > charge nore than an hour. Let me know if you
> figure a way around this 
> > limitation.
> > Bill
> > 
> 
> 


Converting a gen. 5 Honda Civic?  My $20 video/DVD
has my '92 sedan, as well as a del Sol and hatch too! 
Learn more at:
www.budget.net/~bbath/CivicWithACord.html
                          ____ 
                     __/__|__\ __        
  =D-------/    -  -         \  
                     'O'-----'O'-'
Would you still drive your car if the tailpipe came out of the steering wheel? 
Are you saving any gas for your kids?


 
____________________________________________________________________________________
Looking for earth-friendly autos? 
Browse Top Cars by "Green Rating" at Yahoo! Autos' Green Center.
http://autos.yahoo.com/green_center/

--- End Message ---

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