EV Digest 6073
Topics covered in this issue include:
1) RE: brrr cold zero F today
by "Don Cameron" <[EMAIL PROTECTED]>
2) Re: How watts per hour for typical car at 60 miles per hour on
freeway?
by GWMobile <[EMAIL PROTECTED]>
3) Re: Avcon problem
by "Mike Phillips" <[EMAIL PROTECTED]>
4) Re: 2X Alltrax = Curtis ?
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
5) Re: EV controllers? the 4th option...
by "Phil Marino" <[EMAIL PROTECTED]>
6) Re: brrr cold zero F today
by Dave Cover <[EMAIL PROTECTED]>
7) Re: NiMH batteries from GM Ovonics or Panasonic used in EV1, S10 and
Ranger etc.
by "Philippe Borges" <[EMAIL PROTECTED]>
8) Re: I can build your controller
by Rod Hower <[EMAIL PROTECTED]>
9) Chinese controllers
by JS <[EMAIL PROTECTED]>
10) Re: AGM battery charging
by "Paul G." <[EMAIL PROTECTED]>
11) Re: I can build your controller
by Danny Miller <[EMAIL PROTECTED]>
12) Re: brrr cold zero F today
by "Paul G." <[EMAIL PROTECTED]>
13) Re: I can build your controller
by Jack Murray <[EMAIL PROTECTED]>
14) Re: EV controllers? the 4th option...
by "Arthur W. Matteson" <[EMAIL PROTECTED]>
15) Re: Chinese controllers
by "Peter VanDerWal" <[EMAIL PROTECTED]>
16) Re: brrr cold zero F today
by "Joseph H. Strubhar" <[EMAIL PROTECTED]>
17) RE: I can build your controller
by Lock Hughes <[EMAIL PROTECTED]>
18) RE: Avcon problem
by Cor van de Water <[EMAIL PROTECTED]>
19) LiFePo4 Batteries
by "Tom Carpenter" <[EMAIL PROTECTED]>
20) Re: Chinese controllers
by "Roderick Wilde" <[EMAIL PROTECTED]>
21) RE: 2X Alltrax = Curtis ?
by Cor van de Water <[EMAIL PROTECTED]>
22) Re: 2X Alltrax = Curtis ?
by Jack Murray <[EMAIL PROTECTED]>
--- Begin Message ---
Michael, I notice with my ceramic heaters it works better with the fan
blowing at medium speed, instead of high speed. I have both my elements in
the same plane (parallel) and when I have only one turned on the heating is
not very effective as a lot of cold air comes through the other
(disconnected) element. Usually I have both turned on to clear the
windshield.
An option I have been considering for this winter is to have a 120VAC in car
heater. It would be plugged in and turned on about a 1/2 hour before I leave
in the morning.
Don Cameron, Victoria, BC, Canada
see the New Beetle EV project www.cameronsoftware.com/ev
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of mike golub
Sent: October 27, 2006 2:33 PM
To: [email protected]
Subject: brrr cold zero F today
I installed my heater today. It was 0 degrees F when I left the garage this
morning.
One of the pins broke off that Mr.Holmes black box "ceramic" element. So I'm
only powering 2/3rds of it.
I'm using it in a 1986 toyota pu with 120vdc, and curtis upgraded
1209B(120v-550amp) and the vechicle weighs 4100#.
OK so the windsheild was kept clear. That was the major issue. I had the fan
on full blast. The air didn't seem hot at all and I had to run it the entire
time.
Questions
1- Is it OK to use styrofoam to insulate the cab? The stuff is flammable,
but I wonder what type of fire danger there is? Perhaps coat with some fire
barrier stuff? Batt insulation is not flammable, but you need to keep it
dry.
2- If I add the second element. Do I mount it so the air goes through both
or do I just mount in the same plane as the other element. I wonder because
if I added a third one I'd run out of space?
thanks so much...
Michael Golub
Fairbanks, AK
____________________________________________________________________________
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Check out the New Yahoo! Mail - Fire up a more powerful email and get things
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--- End Message ---
--- Begin Message ---
You sleep late :-)
On Fri, 27 Oct 2006 1:23 pm, Michael wrote:
If your numbers are correct how does a car with a 100 mile range
consuming 15kw per hour at 60 mph get recharged overnight by a
receptacle outputting 1.9 kw continous?
Watts per hour is a watt hr.
10 kw for 60 mph driven for one hour is thus 10kw hrs of power.
Is that a trick question? "Overnight" may be 12 hours for many of us...
or
22.8 kWh.
What did I miss?
www.GlobalBoiling.com for daily updated facts about hurricanes,
globalwarming and the melting poles.
www.ElectricQuakes.com daily solar and earthquake data.
--- End Message ---
--- Begin Message ---
Has your avcon adapter worked ever?
Does it have the diode/resistor mounted inside to activate the charger?
Mike
--- In [EMAIL PROTECTED], JS <[EMAIL PROTECTED]> wrote:
>
> My first post:
>
> I visited 5 AVCON chargers, and was able to charge successfully
> from 3. The other two spoke "Charge time exceeded", and shut down
after
> 1 minute.
> They would reset for another minute by pushing the charge button.
>
> My charger is a ZIVAN NG3.
>
> 1. What is the cause?
>
> 2. What is the cure?
>
> John in Sylmar, CA 1981 Electrica Jet conversion with the AVCON
adapter box.
>
--- End Message ---
--- Begin Message ---
I'd love to be there with a video camera when you flip the switch to 96v.
LR..........
----- Original Message -----
From: "damon henry" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, October 27, 2006 12:54 PM
Subject: RE: 2X Alltrax = Curtis ?
> >I'd consider a 144V pack and a single 7245. Arrange the pack as 2 72V
> >strings and parallel them at lower speeds so the controller runs of the
> >72V pack and all batteries are discharged evenly. Above some speed,
> >switch the packs in series and leave the controller connected across
> >only the top 72V segment. This allows the controller to vary voltage to
> >the motor between 72V and 144V.
>
>
> Wow, this is a cool idea. I have been wanting to try a higher voltage on
my
> motorcycle. Since my controller is good for 24 - 48 volts, I could use
this
> techique and try up to 96 volts without buying a new controller.
>
> Damon
>
> _________________________________________________________________
> Find a local pizza place, music store, museum and more.then map the best
> route! http://local.live.com?FORM=MGA001
>
--- End Message ---
--- Begin Message ---
Wow -
Do you really mean $1600 for a 1221C ? $625 shipping is kind of a lot for
a 15 pound box.
Phil
Thanks for the info. A customer of mine just paid 1600 for the 1221C.
That
must have included tax & shipping. LR..........
----- Original Message -----
From: "Phil Marino" <[EMAIL PROTECTED]>
>
> KTA iists a 1221C at $975, the 1231C at $1425, and the Z1K-LV at $1975.
>
> So, the entry-level for a road-going controller is $975, not $1600.
>
> Phil
>
_________________________________________________________________
Add a Yahoo! contact to Windows Live Messenger for a chance to win a free
trip!
http://www.imagine-windowslive.com/minisites/yahoo/default.aspx?locale=en-us&hmtagline
--- End Message ---
--- Begin Message ---
--- mike golub <[EMAIL PROTECTED]> wrote:
> I installed my heater today. It was 0 degrees F when I
> left the garage this morning.
> One of the pins broke off that Mr.Holmes black box
> "ceramic" element.
I'm installing ceramic heaters too and I have a problem that relates to what
you described. In
both the elements I bought the wires are directed straight away from the top. I
need them to come
off at a 90 degree angle, basically parallel to the airflow through the heater.
But I can't bend
the tabs and the metal the wires need to connect to appears to be aluminum. How
do I solder or
bond copper wire to aluminum? Mike, do you have an easy way to reattach the
wire that broke off?
Thanks
Dave Cover
--- End Message ---
--- Begin Message ---
dt/dt don't work on these NIMH !
read below please about NIMH for EPIC Chrysler, they used a special
algorythme:
first step: Charge at C/3 -> dT°C/dt = 9°C/h
then overcharge by 10% of first step less 6Ah
...not easy !
---------------------------------
you can use too:
charging at C/5 or C/4 until having
1.2bar pressure, you just have to adapt one pressure sensor (as motorola MPX
series).
more easy and effective...
Other possibility is this one which looks like lead acid (crude but it works
also)
max initial current C/5, U given at 20°C ambiant
Type U temp Compensation time
Bulk 14.6V -17.5mV/°C -> U
Absorption 14.6V -17.5mV/°C 2h
Floating 14.1V -17.5mV/°C Permanent
you absoluely need liquid cooling during charge and also discharge (better
for life)
Temp security at 50°C max(charge/discharge) otherwise AH will go definitely
down.
These cells prefer not being charged to 100% and not being discharged to
less than 20%
best usage windows for maximum cyclic life is 20% min 80% max as lithium
in fact.
these are very fragile but good game with these maravelous cells :^)
thise is a copy of an email i send about saft NIMH:
cordialement,
Philippe
Et si le pot d'échappement sortait au centre du volant ?
quel carburant choisiriez-vous ?
http://vehiculeselectriques.free.fr
Forum de discussion sur les véhicules électriques
http://vehiculeselectriques.free.fr/Forum/index.php
----- Original Message -----
From: "Ray Wong" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, October 27, 2006 10:58 PM
Subject: Re: NiMH batteries from GM Ovonics or Panasonic used in EV1, S10
and Ranger etc.
> The Nimh are still near my bench with big lab power supplies and lab data
acquisition equipment and load banks. My auto EV project are not up and
running yet.
>
> I may end up using an Agilent 34970 to monitor the temperature and
control the constant current charger. I have a Link10 with RS232 to give me
some additional data but I think temperature monitoring may be the best way
to charge these batteries. Right now I charge at 20 amps until I see a rise
in temperature, then I back off the current for a top off period. If you
had a basic constant current charger and a stand alone Omega multi-input
temperature alarm, you could probably charge just fine. A backup timer
would be helpful. Maybe a low constant current equalize every once in a
while.
>
> I am sure the RAV4 EV has a good charge algorithm. Anyone know what
they do?
>
> If you avoid the reverse polarity on discharge and overheating due to
overcharging, then these cells will last a real long time. Mine are at
least 6 years old and probably quite a few hundred cycles, yet they seem to
give me almost a full rated charge once I removed the bad cells. I am sure
that a few more cells may fail after a few hundred more cycles but if they
get swapped out, the pack will be good for many more cycles.
>
> I have heard of up to 100,000 miles on these batteries with 80% of
capacity. IMHO, the 80% capacity can be kept higher if only a few bad cells
are replaced. The majority of the cells seem to be at full capacity.
>
> The Prius has NiMh batteries that are said to last longer than the
vehicle. They can do this by keeping the battery operating in a safe middle
zone, never discharge too much, never overcharge too much. Adding the EV
switch to a Prius will reduce the life of the battery considerably as you
are now discharging much further and risking a cell reversal.
>
>
> Ezesport
>
>
> [EMAIL PROTECTED] wrote:
> That is waht I was thinking also, there may be a cell or two dead and
with
> rearrangement, some work can be done.
> What BMS module did you use? Any details will be welcome, thanks
> JJ
>
> > I bought 18 of these M-95 from a Ranger pack that were considered dead.
> > It took a lot of time but I now have 16 good packs that test to around
> > 90ah at C/2.
> >
> > The battery pack can be rebuilt if you have spare cells. Most of the
> > time there was only one cell that died on each battery.
> >
> > Too bad there are not a lot of these around. Someone sold 17 of these
> > on ebay for $5500 just last week.
> >
> > Ezesport
> >
> >
> > Death to All Spammers wrote:
> > > Well, that don't make these anymore, so any you find (and where the
> > heck
> >> did you find any?) are probably 6-8 years old and may very well be
> > near
> >> the end of their useful life.
> >> Personally, I'd prefer ones that have been tested to insure they
> > still
> >> work. The untested, uncharged ones might yield somewhere in the
> >> neighborhood of zero.
> >>
> >
> > But think of what a find if you discovered a cache of several hundred
> > Panasonic 95AH cells - even if untested and never charged, it would be
> > worth evaluating each one for potential use, since they aren't suppose
> > to have the same calender issues. Then again, it's most likely a
> > pipedream.
> >
> >
> >
> >
> >
> > ---------------------------------
> > How low will we go? Check out Yahoo! Messenger's low PC-to-Phone call
> > rates.
>
>
>
>
>
> ---------------------------------
> Want to start your own business? Learn how on Yahoo! Small Business.
>
--- End Message ---
--- Begin Message ---
I work for Ametek-Rotron that produces many different
products including universal brush motors used in
vacuum cleaners, leaf blowers etc. We have had
Chinese companies reproduce our product even using our
own CAD drawings for reference! It's pretty easy to
duplicate a universal motor when your cousin 'Chen'
has all of the prints available at a factory down the
street. He then sells this product at less than our
material cost!
I also deal with Chinese vendors that make a very nice
product to our specifications at a very low cost (a
casting for my 60A, 28Volt BLDC motor control used on
transit busses for air conditioning/heating). I'm
very happy with the product I received at a cost
effective price.
I think we need to take a close look at the Zilla
design.
They can build it at a low cost and with the proper
business contracts reward Otmar with his current
profit margin. The end product is a lower cost
control.
If company 'B' down the street tries to duplicate the
Zilla they will need the software. I'm assuming Otmar
has protected his Atmel devices against copying.
So if you buy the Chinese copy you'll have the
insecurity of no support if there are problems. I
would prefer to buy a Chinese Zilla with royalties
paid to Otmar over a cheaper duplicate with no
guarantee they will ever give you support.
The only negative here is paying for labor in China
instead of people here in the states. I guess that is
the philosophical dilema here. If the cost difference
is enough to get many more EV's on the road, I would
go for the Chinese royalty based control. I guess the
people out of a job building a Zilla could concentrate
on building EV's in the states?
One more curveball to throw in. Rich Rudmans charger
or proposed control with analog only (no MCU) could be
easily duplicated since there is no proprietary
software. I guess if the market gets big enough this
is something Rich will have to consider.
Rod
--- End Message ---
--- Begin Message ---
While I try to buy American, and resent much of the Chinese competition,
I recognize they are potentially the world's worst polluter.
If they could supply a really cheap but reliable controller (and other
EV parts)
it would encourage them to build EVs for home use.
It could be an entry level controller here in the USA.
And we could keep the good high-tech stuff made here,
as long as possible.
If we cannot get the U.S. auto makers interested in EV
maybe China will.
John in Sylmar, CA
--- End Message ---
--- Begin Message ---
On Oct 27, 2006, at 7:13 AM, Storm Connors wrote:
It is a war surplus (actually 2 of them in series) which have huge
multitap transformers. I can set the voltage. The amperage adjusts
itself. I guess my concern is the drop in voltage. I did not expect it
and don't have any idea what would cause it.
Could the acceptance voltage be as high as 193.3v in a 144v pack?
No! That will cook an AGM after a while. That can be acceptable for an
equalize (at perhaps 1 amp per 25 ah of capacity for up to 1 hour), but
it shouldn't be done at higher amps or for longer times.
That charger can work, but you want to set the taps so the pack voltage
doesn't exceed 180 volts. Even this needs to be done with care because
you need to keep each battery under 15 volts (at least before you do an
equalize finish.) This is where old/mismatched batteries can be a pain.
They start coming up together but then some get past the bulk charge
phase before the others and the voltages start going all over the
place. That is when you have to be there, check each battery, and keep
the charger taps set to hold keep the pack charging without hurting the
batteries that want to go over voltage early.
Paul "neon" G.
--- End Message ---
--- Begin Message ---
I'm an electrical engineer with a lot of PIC microcontroller
experience. The controls, even being full-featured, are a no-brainer.
The power stage, high current traces, and mechanical connections are a
bit of a trick. Well, not really a mystery but it's not something I
have more than textbook knowledge of.
Danny
Rocketjosh wrote:
I have much respect for the others making Controllers, I have one problem,
however-I cant get a quality controller at a reasonable price nor a reasonable
time-frame. I see an opportunity to provide a more reliable source of quality
controllers.
I have no intention of taking any business away from anyone. I want to work
with someone that is well versed in controller design, and HELP them build
something. Neither Otmar nor Rich are interested, I offered my help directly to
them already. Why not leave the Design work to the experts and the
Manufacturing to the experts?
By the way. the reason I ask for some basic information (BOM, schematic, etc)
is to get an INITIAL estimate of cost. How much will the parts cost is sourced
overseas? If we find that the cost of the parts is encouraging, then we take
the next step.
Here is my proposal: Someone acts as the Electrical Engineer providing
specifications for the controller and support during prototype development and
testing. They get Royalties for every unit sold in return.
In the end, more EVs will be built as a result of our work. Isn't that our
ultimate goal after all?
Josh
David Roden <[EMAIL PROTECTED]> wrote: Josh wrote :
I work in the consumer electronics industry ... I have visited
many factories in China and work closely with overseas
manufacturers and suppliers.
Warning, rant ahead!
Great, just what we need, twenty cent an hour Chinese sweatshop labor to
bury the good folks on the list who make their living, such as it is,
building high quality EV components.
Josh, I'll give you the benefit of the doubt since (I think) you're a newbie
here, but how about a little concern for guys like Rich and Otmar, our
friends who work with list members to build what they want and produce a
high quality product? Rich at least has gone into debt to do this.
These guys are producing handbuilt products at mass-production prices, and
damn reasonable ones at that. I doubt that they're getting rich on it, but
they are doing us a real service. Take their living away from them and you
can forget them ever taking part in EVs as a business again.
Sorry if I seem a bit annoyed about this - I am. If we had nobody at all
building the components we need, it would be a different matter, but we are
lucky to have people who do - and whom we can literally call up for help and
support (try that with the guys in China).
I don't want a fight, and I don't want to seem ungrateful, but I really wish
you would take your Chinese manufacturing connections somewhere else and use
them for something else.
David Roden - Akron, Ohio, USA
EV List Assistant Administrator
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--- End Message ---
--- Begin Message ---
On Oct 27, 2006, at 2:32 PM, mike golub wrote:
I installed my heater today. It was 0 degrees F when I
left the garage this morning.
One of the pins broke off that Mr.Holmes black box
"ceramic" element. So I'm only powering 2/3rds of it.
I'm using it in a 1986 toyota pu with 120vdc, and
curtis upgraded 1209B(120v-550amp) and the vechicle
weighs 4100#.
OK so the windsheild was kept clear. That was the
major issue. I had the fan on full blast. The air
didn't seem hot at all and I had to run it the entire
time.
Well, get the whole element working first but expect to add another. If
you have a 5 tab heater then one broken pin could put 2 of the 4 rows
out of work (50%.) An end pin would put 25% of the same heater out of
work.
After the windshield is clear try slowing the fan speed. Ceramic
heaters can often put out more heat with less than a heater fan's
highest airflow. The ceramic elements are designed to have a some what
high resistance when cold, then it drops as they warm, then increases
rapidly as they get to hot. The airflow that causes the maximum amps to
flow will create the most heat (volts times amps equals watts - in this
case watts of heat.)
If you are seeing less than 20F outside temps you will need 2 ceramic
heaters (IMHO - and I like it warm.) Generally, they are placed side by
side. It lowers the airflow rate to help them operate at a temperature
that maximizes the amps they can draw. Its an EV efficiency side effect
(since the motor and controller are so much more efficient than an ICE
we don't have "free" waste heat.)
The VW Pickup I built (it now belongs to Don) was equipped with 2, 1500
watt, ceramic heaters. I found that to be great down to 30F and quite
acceptable for the colder days (not that we have that many in western
WA.) Above freezing I generally only ran 1 heater after using both to
initially warm the cab. I never ran the fan on high unless it was just
to defog the windshield. There was a lot more heat available on speed 1
or 2.
HTH,
Paul "neon" G.
--- End Message ---
--- Begin Message ---
Josh is only saying he has a contact in China to manufacture product,
The issue is having a design to produce.
The design, bom, schematics, firmware, etc, comes from a lot of expense
and hard work prototyping, debugging, and testing. High voltage and
current circuits are not trivial, they blow out traces on boards, I've
had boards catch on fire even, and risk bodily injury to debug them.
The fact that the Chinese do not take seriously US laws on intellectual
property (remember China is still a Communist country, some seem to
forget) would give me pause to release the designs to them.
I've had my R/C boards manufactured by a company in Los Angeles.
Jack
Danny Miller wrote:
I'm an electrical engineer with a lot of PIC microcontroller
experience. The controls, even being full-featured, are a no-brainer.
The power stage, high current traces, and mechanical connections are a
bit of a trick. Well, not really a mystery but it's not something I
have more than textbook knowledge of.
Danny
Rocketjosh wrote:
I have much respect for the others making Controllers, I have one
problem, however-I cant get a quality controller at a reasonable price
nor a reasonable time-frame. I see an opportunity to provide a more
reliable source of quality controllers.
I have no intention of taking any business away from anyone. I want to
work with someone that is well versed in controller design, and HELP
them build something. Neither Otmar nor Rich are interested, I offered
my help directly to them already. Why not leave the Design work to the
experts and the Manufacturing to the experts?
By the way. the reason I ask for some basic information (BOM,
schematic, etc) is to get an INITIAL estimate of cost. How much will
the parts cost is sourced overseas? If we find that the cost of the
parts is encouraging, then we take the next step.
Here is my proposal: Someone acts as the Electrical Engineer providing
specifications for the controller and support during prototype
development and testing. They get Royalties for every unit sold in
return.
In the end, more EVs will be built as a result of our work. Isn't that
our ultimate goal after all?
Josh
David Roden <[EMAIL PROTECTED]> wrote: Josh wrote :
I work in the consumer electronics industry ... I have visited many
factories in China and work closely with overseas manufacturers and
suppliers.
Warning, rant ahead!
Great, just what we need, twenty cent an hour Chinese sweatshop labor
to bury the good folks on the list who make their living, such as it
is, building high quality EV components.
Josh, I'll give you the benefit of the doubt since (I think) you're a
newbie here, but how about a little concern for guys like Rich and
Otmar, our friends who work with list members to build what they want
and produce a high quality product? Rich at least has gone into debt
to do this.
These guys are producing handbuilt products at mass-production prices,
and damn reasonable ones at that. I doubt that they're getting rich
on it, but they are doing us a real service. Take their living away
from them and you can forget them ever taking part in EVs as a
business again.
Sorry if I seem a bit annoyed about this - I am. If we had nobody at
all building the components we need, it would be a different matter,
but we are lucky to have people who do - and whom we can literally
call up for help and support (try that with the guys in China).
I don't want a fight, and I don't want to seem ungrateful, but I
really wish you would take your Chinese manufacturing connections
somewhere else and use them for something else.
David Roden - Akron, Ohio, USA
EV List Assistant Administrator
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Want to unsubscribe, stop the EV list mail while you're on vacation,
or switch to digest mode? See how: http://www.evdl.org/help/
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Note: mail sent to "evpost" or "etpost" addresses will not reach me.
To send a private message, please obtain my email address from
the webpage http://www.evdl.org/help/ .
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
---------------------------------
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--- End Message ---
--- Begin Message ---
I know some have been confused about why one would choose a module for a
DC controller that has "wasted" parts. This seems counter-intuitive.
The reason my [quickly progressing] semi-open-source DC motor controller
uses half-bridge modules is the following:
- Stray inductance! -
When you're working with levels of 500A, effects of stray inductance are
everywhere. If you used a single switch and an external diode, you'd
have no good way of clamping the switch voltage because the path would
be too long. This is a good way to explode a module at about 300V out
of the 600V rating, under the right [wrong] conditions.
When you look at many of the half-bridge modules, you'll notice that
they put the "P" and "N" terminals right next to each other, instead of
first and third as intuition would have it. The novice power engineer
remarks, "Hmm, that's strange!" In my design, I have a snubber
capacitor right across these terminals:
(505-SM2.2/630/5A1 from Mouser)
http://tinyurl.com/y9cpls
> This doesn't work with IGBTs. Even the best of them have twice the
> voltage drop of a good diode.
* A single tear falls from Arthur's face... *
IGBTs don't conduct in both directions. So the voltages don't even
matter. Even if an IGBT had a Vce(sat) of 0.1V, the direction of
current would be wrong. They can't be used as synchronous rectifiers at
all. Neither can BJTs (bipolar junction transistors). MOSFETs,
however, do conduct in both directions. This is the notion of a
pass-transistor in CMOS design.
Imagine plotting the V-I curve for each type of switching device.
You'll find: IGBTs/BJTs have one-quadrant conduction; MOSFETs have
two-quadrant conduction; SCRs have one-quadrant conduction; TRIACs have
two-quadrant conduction (though not the same two quadrants as the
MOSFET).
There are many resources on the Internet for learning about
semiconductor operation (although not so much on power electronics).
All three of my graduate courses deal with semiconductors, and I'd be
happy to send "slides" to anyone.
- Arthur
On Fri, 2006-10-27 at 12:38 -0500, Lee Hart wrote:
> Cor van de Water wrote:
> > I think we were mainly focusing on DC controllers...
> > Your module suggestions are for AC drive...
>
> The modules don't actually care, AC or DC. A DC controller is basically
> a "half bridge" AC controller.
>
> > The only reason to use this module for DC would be
> > to use one (switching) transistor plus the freewheel
> > diode from the other transistor to get the two power
> > parts in one package (and not use the other two).
>
> I suggested MOSFET modules, where you have a MOSFET for both the switch
> and freewheel. MOSFETs are faster and can have a lower on-state voltage
> drop than diodes. Replacing the diode with a MOSFET improves efficiency
> and reduces heating.
>
> This doesn't work with IGBTs. Even the best of them have twice the
> voltage drop of a good diode.
--- End Message ---
--- Begin Message ---
China is probably already the leading producer and consumer of electric
vehicles. I doubt they need much encouragement, or any help building
controllers.
> While I try to buy American, and resent much of the Chinese competition,
> I recognize they are potentially the world's worst polluter.
>
> If they could supply a really cheap but reliable controller (and other
> EV parts)
> it would encourage them to build EVs for home use.
>
> It could be an entry level controller here in the USA.
> And we could keep the good high-tech stuff made here,
> as long as possible.
>
> If we cannot get the U.S. auto makers interested in EV
> maybe China will.
>
> John in Sylmar, CA
>
>
--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.
--- End Message ---
--- Begin Message ---
How about a flag terminal, one that crimps on the wire at a 90 degree angle
to the tab?
Joseph H. Strubhar
E-mail: [EMAIL PROTECTED]
Web: www.gremcoinc.com
----- Original Message -----
From: "Dave Cover" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, October 27, 2006 3:42 PM
Subject: Re: brrr cold zero F today
> --- mike golub <[EMAIL PROTECTED]> wrote:
>
> > I installed my heater today. It was 0 degrees F when I
> > left the garage this morning.
> > One of the pins broke off that Mr.Holmes black box
> > "ceramic" element.
>
> I'm installing ceramic heaters too and I have a problem that relates to
what you described. In
> both the elements I bought the wires are directed straight away from the
top. I need them to come
> off at a 90 degree angle, basically parallel to the airflow through the
heater. But I can't bend
> the tabs and the metal the wires need to connect to appears to be
aluminum. How do I solder or
> bond copper wire to aluminum? Mike, do you have an easy way to reattach
the wire that broke off?
>
> Thanks
>
> Dave Cover
>
>
>
>
> --
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.1.408 / Virus Database: 268.13.17/505 - Release Date:
10/27/2006
>
>
--- End Message ---
--- Begin Message ---
I like to think of Yong Kang, Zhejiang. Last time I checked, over 300
companies all making EV's (assembling, or manufacturing parts for
e-scoots, and both. When they're not making pots and pans, or wire
brushes...)
This with a population of about 1/2 Mil.
China's "Hardware Capital" by reputation. For centuries.
Also, China's capital for amputations by industrial accident.
I always suggest folks buying the Chinese e-scoots check the box, for
extra parts.
:)
tks
Lock
Toronto
Human/Electric Hybrid Pedestrian
--- Don Cameron <[EMAIL PROTECTED]> wrote:
> Josh, since I am not an EE I cannot offer much except my vote of
> support.
> Notwithstanding Dave's concerns about China, you might find the list
> a
> little negative at times, finding problems rather than solutions. It
> might
> be a bit of an uphill struggle. However, persevere and you should be
> rewarded with customers who simply want to get their conversions done
> and on
> the road.
>
>
>
>
> Don Cameron, Victoria, BC, Canada
>
> see the New Beetle EV project www.cameronsoftware.com/ev
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
> On
> Behalf Of Rocketjosh
> Sent: October 27, 2006 11:31 AM
> To: [email protected]
> Subject: Re: I can build your controller
>
> I have much respect for the others making Controllers, I have one
> problem,
> however-I cant get a quality controller at a reasonable price nor a
> reasonable time-frame. I see an opportunity to provide a more
> reliable
> source of quality controllers.
>
> I have no intention of taking any business away from anyone. I want
> to work
> with someone that is well versed in controller design, and HELP them
> build
> something. Neither Otmar nor Rich are interested, I offered my help
> directly
> to them already. Why not leave the Design work to the experts and the
> Manufacturing to the experts?
>
> By the way. the reason I ask for some basic information (BOM,
> schematic,
> etc) is to get an INITIAL estimate of cost. How much will the parts
> cost is
> sourced overseas? If we find that the cost of the parts is
> encouraging, then
> we take the next step.
>
> Here is my proposal: Someone acts as the Electrical Engineer
> providing
> specifications for the controller and support during prototype
> development
> and testing. They get Royalties for every unit sold in return.
>
> In the end, more EVs will be built as a result of our work. Isn't
> that our
> ultimate goal after all?
>
> Josh
>
> David Roden <[EMAIL PROTECTED]> wrote: Josh wrote :
>
> > I work in the consumer electronics industry ... I have visited many
>
> > factories in China and work closely with overseas manufacturers and
>
> > suppliers.
>
> Warning, rant ahead!
>
> Great, just what we need, twenty cent an hour Chinese sweatshop labor
> to
> bury the good folks on the list who make their living, such as it is,
> building high quality EV components.
>
> Josh, I'll give you the benefit of the doubt since (I think) you're a
> newbie
> here, but how about a little concern for guys like Rich and Otmar,
> our
> friends who work with list members to build what they want and
> produce a
> high quality product? Rich at least has gone into debt to do this.
>
> These guys are producing handbuilt products at mass-production
> prices, and
> damn reasonable ones at that. I doubt that they're getting rich on
> it, but
> they are doing us a real service. Take their living away from them
> and you
> can forget them ever taking part in EVs as a business again.
>
> Sorry if I seem a bit annoyed about this - I am. If we had nobody at
> all
> building the components we need, it would be a different matter, but
> we are
> lucky to have people who do - and whom we can literally call up for
> help and
> support (try that with the guys in China).
>
> I don't want a fight, and I don't want to seem ungrateful, but I
> really wish
> you would take your Chinese manufacturing connections somewhere else
> and use
> them for something else.
>
>
> David Roden - Akron, Ohio, USA
> EV List Assistant Administrator
>
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> Want to
> unsubscribe, stop the EV list mail while you're on vacation, or
> switch to
> digest mode? See how: http://www.evdl.org/help/ = = = = = = = = = =
> = = = =
> = = = = = = = = = = = = = = = = = = =
> Note: mail sent to "evpost" or "etpost" addresses will not reach me.
>
> To send a private message, please obtain my email address from the
> webpage
> http://www.evdl.org/help/ .
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
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>
>
>
> ---------------------------------
> Get your email and more, right on the new Yahoo.com
>
>
__________________________________________________
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--- End Message ---
--- Begin Message ---
Most likely dirty contacts.
I think Bruce told the same story,
wiggling the connecctor and/or
scraping the contacts can help.
Success,
Cor van de Water
Systems Architect
Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [EMAIL PROTECTED]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-610-423-5743
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of JS
Sent: Friday, October 27, 2006 11:34 AM
To: [email protected]
Subject: Avcon problem
My first post:
I visited 5 AVCON chargers, and was able to charge successfully
from 3. The other two spoke "Charge time exceeded", and shut down after
1 minute.
They would reset for another minute by pushing the charge button.
My charger is a ZIVAN NG3.
1. What is the cause?
2. What is the cure?
John in Sylmar, CA 1981 Electrica Jet conversion with the AVCON adapter box.
--- End Message ---
--- Begin Message ---
Has any one read or seen the LiFePo4 batteries on the power stream sight?????
Tom
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: "JS" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, October 27, 2006 4:32 PM
Subject: Chinese controllers
While I try to buy American, and resent much of the Chinese competition,
I recognize they are potentially the world's worst polluter.
If they could supply a really cheap but reliable controller (and other EV
parts)
it would encourage them to build EVs for home use.
It could be an entry level controller here in the USA.
And we could keep the good high-tech stuff made here,
as long as possible.
If we cannot get the U.S. auto makers interested in EV
maybe China will.
John in Sylmar, CA
--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.408 / Virus Database: 268.13.16/504 - Release Date:
10/27/2006
--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.408 / Virus Database: 268.13.16/504 - Release Date: 10/27/2006
--- End Message ---
--- Begin Message ---
Please do not try this at home.
Some people have tried adding an extra 12V battery in
series with a 36V controller and gotten away with it,
but if you double the pack voltage, the following
can happen to the controller:
- the voltage (back-EMF) on the motor is lower than
half the pack voltage, so the controller gets more
volts than what it's built for and dies
(example: at 72V the back-EMF due to the motor RPM
may be 40V, when switched to 144V this means 104V
divided between controller and motor, when you
release the throttle, the controller goes boom.
- the controller sees a negative motor voltage, because
for the controller at 72V the motor is connected to -72
which can cause a polarised device in the controller to
fail.
- Dependent on the controller design, the freewheel diode
may be conducting continuously without throttle, sending
full 72V and high current to the motor, with throttle
you will be switched to 144V but the continuous current
may be overloading the freewheel diode(s).
- If controller goes in current limit, the voltage on
the motor can easily drop below 72V, so the controller
sees more than 72V.
- Probably there are other issues that depend on the
design of the controller, so only inspection of it
can tell you if this idea is even feasible.
You do have a big chance of blowing up your controller,
it is on you if you want to test it or use a controller
fit for the job.
Success,
Cor van de Water
Systems Architect
Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [EMAIL PROTECTED]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-610-423-5743
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of damon henry
Sent: Friday, October 27, 2006 12:55 PM
To: [email protected]
Subject: RE: 2X Alltrax = Curtis ?
>I'd consider a 144V pack and a single 7245. Arrange the pack as 2 72V
>strings and parallel them at lower speeds so the controller runs of the
>72V pack and all batteries are discharged evenly. Above some speed,
>switch the packs in series and leave the controller connected across
>only the top 72V segment. This allows the controller to vary voltage to
>the motor between 72V and 144V.
Wow, this is a cool idea. I have been wanting to try a higher voltage on my
motorcycle. Since my controller is good for 24 - 48 volts, I could use this
techique and try up to 96 volts without buying a new controller.
Damon
_________________________________________________________________
Find a local pizza place, music store, museum and more...then map the best
route! http://local.live.com?FORM=MGA001
--- End Message ---
--- Begin Message ---
Well I didn't try it, but after thinking it through the fets will see
the full voltage differential even if the control circuits do not, and
will blow, so that is enough to convince me.
However, one option is to have the controller by-passed with some
contactors for a full-on at higher voltage for top speed. A "turbo"
button so to speak. Is it worth all the trouble? maybe, probably
blow-up at least one controller debugging it.
Jack
Cor van de Water wrote:
Please do not try this at home.
Some people have tried adding an extra 12V battery in
series with a 36V controller and gotten away with it,
but if you double the pack voltage, the following
can happen to the controller:
- the voltage (back-EMF) on the motor is lower than
half the pack voltage, so the controller gets more
volts than what it's built for and dies
(example: at 72V the back-EMF due to the motor RPM
may be 40V, when switched to 144V this means 104V
divided between controller and motor, when you
release the throttle, the controller goes boom.
- the controller sees a negative motor voltage, because
for the controller at 72V the motor is connected to -72
which can cause a polarised device in the controller to
fail.
- Dependent on the controller design, the freewheel diode
may be conducting continuously without throttle, sending
full 72V and high current to the motor, with throttle
you will be switched to 144V but the continuous current
may be overloading the freewheel diode(s).
- If controller goes in current limit, the voltage on
the motor can easily drop below 72V, so the controller
sees more than 72V.
- Probably there are other issues that depend on the
design of the controller, so only inspection of it
can tell you if this idea is even feasible.
You do have a big chance of blowing up your controller,
it is on you if you want to test it or use a controller
fit for the job.
Success,
Cor van de Water
Systems Architect
Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [EMAIL PROTECTED]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-610-423-5743
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of damon henry
Sent: Friday, October 27, 2006 12:55 PM
To: [email protected]
Subject: RE: 2X Alltrax = Curtis ?
I'd consider a 144V pack and a single 7245. Arrange the pack as 2 72V
strings and parallel them at lower speeds so the controller runs of the
72V pack and all batteries are discharged evenly. Above some speed,
switch the packs in series and leave the controller connected across
only the top 72V segment. This allows the controller to vary voltage to
the motor between 72V and 144V.
Wow, this is a cool idea. I have been wanting to try a higher voltage on my
motorcycle. Since my controller is good for 24 - 48 volts, I could use this
techique and try up to 96 volts without buying a new controller.
Damon
_________________________________________________________________
Find a local pizza place, music store, museum and more...then map the best
route! http://local.live.com?FORM=MGA001
--- End Message ---
