EV Digest 5394
Topics covered in this issue include:
1) Re: Lead prices
by Neon John <[EMAIL PROTECTED]>
2) Re: AC vs DC; Newbie Question
by Wayne <[EMAIL PROTECTED]>
3) Re: Poor-Boy'N It
by Wayne <[EMAIL PROTECTED]>
4) Re: Otmar's motor speed sensor - Kostov's
by James Massey <[EMAIL PROTECTED]>
5) Re: Albright Contactor rework
by "Roland Wiench" <[EMAIL PROTECTED]>
6) Targa car, was: Re: longest range?
by James Massey <[EMAIL PROTECTED]>
7) battery monitor, what's up
by elaine chiu <[EMAIL PROTECTED]>
8) Re: Low rider floodie quest
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
9) Re: AGM + flooded together, quick and low cost per mile?
by [EMAIL PROTECTED] (Brad Baylor)
10) Re: Neon (Lamp, not John) Questions
by Victor Tikhonov <[EMAIL PROTECTED]>
11) Re: Otmar's speed sensor
by Jeff Shanab <[EMAIL PROTECTED]>
12) Re: Switched Capacitor Equalization of Long Strings WAS: Some
problemstosolve
by Victor Tikhonov <[EMAIL PROTECTED]>
13) RE: Albright Contactor rework
by "Bill Dennis" <[EMAIL PROTECTED]>
14) Re: Arctic Leash
by Victor Tikhonov <[EMAIL PROTECTED]>
15) New Panasonic car runs off two AA batteries
by "Dr. Polsinelli" <[EMAIL PROTECTED]>
16) Re: battery monitor, what's up
by Lee Hart <[EMAIL PROTECTED]>
17) Re: Targa car, was: Re: longest range?
by Victor Tikhonov <[EMAIL PROTECTED]>
18) article: PARATRANSIT, INC. AND HYBRID TECHNOLOGIES INC. (NASD OTCBB:
HYBT) ANNOUNCE JOINT VENTURE IN SACRAMENTO THAT WILL BE FIRST LITHIUM VEHICLES
USED FOR TAXIS
by Paul Wujek <[EMAIL PROTECTED]>
19) Re: article: PARATRANSIT, INC. AND HYBRID TECHNOLOGIES INC. (NASD OTCBB:
HYBT) ANNOUNCE JOINT VENTURE IN SACRAMENTO THAT WILL BE FIRST LITHIUM VEHICLES
USED FOR TAXIS
by "Ryan Stotts" <[EMAIL PROTECTED]>
20) Re: New Panasonic car runs off two AA batteries
by "Ryan Stotts" <[EMAIL PROTECTED]>
21) Low battery voltage limit and signage
by Jeff Shanab <[EMAIL PROTECTED]>
22) Aero Drag Significance ?
by "jmygann" <[EMAIL PROTECTED]>
23) Re: Albright Contactor rework
by Neon John <[EMAIL PROTECTED]>
24) Re: Albright Contactor rework
by Neon John <[EMAIL PROTECTED]>
25) Re: Switched Capacitor Equalization of Long Strings WAS: Some
problemstosolve
by Neon John <[EMAIL PROTECTED]>
--- Begin Message ---
On Fri, 21 Apr 2006 16:35:30 -0000, "Mike Phillips"
<[EMAIL PROTECTED]> wrote:
>I was curious why lead is getting so pricey. It's been a trend for
>some years. Here was a great page of information.
>
>http://www.batteriesdigest.com/id385.htm
All metals are way up, generally blamed on the chinese.
Scrap copper is higher than it's been in 20 years which has resulted
in two recent events - My friend Jerry, my friendly local electric
motor fixer-upper sold about 20k lbs of scrap copper windings that
he'd been storing for several years and then went on vacation :-) and
b) about 2 weeks ago someone stole a central air conditioner from the
flat roof of my restaurant building. Along with one of my grease
hood's vent fans and my ladder, after they cut the lock off.
Can you imagine lugging a 5 ton AC unit off a 20 ft high roof? The
cop that investigated my theft said that mine was the third he's done
in the last few weeks.
John
---
John De Armond
See my website for my current email address
http://www.johngsbbq.com
Cleveland, Occupied TN
Don't let your schooling interfere with your education-Mark Twain
--- End Message ---
--- Begin Message ---
So, to continue (and to express more thanks for the input regarding
AC vs DC; including side-bars...
After reading and "listening" it became apparent to me that I lack
the mechanical skills (I knew it all along) to do a conversion
justice. So, I got in touch with the local Tech School about them
doing a conversion for me...The head of the automotive department
answered saying that they were very interested in the project and
even offered a Ford Probe as a donor car (providing I would run a
decal saying who did the conversion)...My plan was to give them
credit regardless. I think the kids going to tech schools need as
much exposure to the future as we can provide...Who knows, maybe one
of them will open a conversion shop here in Central MO and become a
raging success!
Anyhoo...The Probe is a pretty heavy vehicle weighing in at just
under 2700 lbs (add 800+ and we're easily pushing 3500#). What's it
gonna take to get this beast moving? I had hoped to convert a GEO
Metro or Ford Festivia (or something of similar ilk) going up to 96,
maybe 120 v (DC), regen. Basically a small 40 to 50 mile
around-towner. However, the offer of the "free" donor may be an
offer too good to turn down. The only problem with the Probe of
which I'm aware is that it needs a tranny...Surely a 4 or 5 speed
manual can't be THAT prohibitively expensive...Or can it?
I'm waiting for word as to the year and model, original engine size
and so on but in the interm, what's your thoughts on the Probe as a
conversion...What's the best motor size, battery pack size? Any
other advise as to components?
I'm starting to get buzzed about this...Even the wife is on board
(she won't let me sell my grocery-getter just yet, but we'll cross
that bridge when the time comes)...
Again, many thanks for all your help and guidance...I hope I can
repay the list some day...
Wayne
If those of us who "can", "do" then those of us who "can't" won't
suffer as much from the high prices of excess.
--- End Message ---
--- Begin Message ---
I didn't forget y'all...Just got sidetracked...
I want to thank each and every one of you for your advise and
suggestions, comments and sidebars...
I got in touch with the local Tech School and, well, more to follow...
Thanks again,
Wayne
At 02:50 PM 4/4/2006, you wrote:
As a rank Newbie, I'm hoping to give myself a little OJT by
building/converting a riding lawn mower to electric. As this is an
merely a first attempt to physically climb the learning curve, cost
is an significant factor.
I've ordered "Convert It!" and "Build Your Own EV," but at the time
of this writing, neither has arrived.
I'll most likely use an old Murry/Sears junked rider, 36" or
something along those lines. I'll need a "range" of about 1/2 acre
that lays, for the most part, on a fairly gentle slope, say, 7-8%
(aprx 5 deg; Tan 5 deg*100) with one fairly steep section about
55-60% (aprx 30 deg) for 30-40 feet.
I'd like to use standard automotive batteries but if they won't do
the job, I'll spring for a set of more serious batteries. How many
batteries/total voltage/type/brand?
What would be a good, cheap drive motor and (pair of) blade
motors? The operative adjective being "cheap."
What would be the minimum speed regulating device? It would be
false economy for me to spring for sophisticated devices at this point.
As you can tell by these questions, 1've only my toe dipped in the
shallow end of a very deep learning pool.
I appreciate any and all assistance.
Wayne White
If those of us who "can", "do" then those of us who "can't" won't
suffer as much from the high prices of excess.
--- End Message ---
--- Begin Message ---
At 02:07 PM 21/04/06 -0700, Rich Rudman wrote:
<snip>
What I was envisioning is somthing that bolts onto the Fan end shaft so I
just install the sensor housing that Otmar sells. Since I have one...
The problem is I AM KEEPING THE DARN FAN.!!!!! I need all the cooling I can
get... and I know when and how it works. Hot days means I run in 1st up
against the Rev limiter... The vacume cleaner sounds tells me I am sucking
LOTS of air.. I don't have to be trained to not Lug my motors. ...I just
need the darn tach to work so I don't screw up.
G'day Rich, and all
Take the rotor with its fan on it to a machine shop that has a milling
machine and a dividing head. Get them to "castellate" the outer edge of the
fan main disk (if you layed it out straight it'd be
___---___---___---___--- ). I've had my aluminium "flywheel" (clutch
carrier) machined like this - although the machinist didn't follow the
instruction of 50% cut, 50% left, he only cut a tool width.
http://jcmassey.gallery.netspace.net.au/Daihatsu-pics-01/Image_093 - there
is a notch cut visible on top. I am going to be using an inductive
proximity switch, like what they use on rally cars to count the back of the
wheel studs for their trip meters. Yes, I know that you can use much
cheaper sensors - but an inductive prox is sealed, waterproof, dustproof,
doesn't have magnetic targets to fall off, simple to install...
If you want to use a magnetic sensor, drill some holes through the plate of
the fan close to the edge, and epoxy some supermagnets into the holes.
Just my $0.02
Regards
James
--- End Message ---
--- Begin Message ---
Hello All,
How about using a voltage divider across your battery pack to get the
voltage you need.
On my 180 volt pack, I install a 2k, 28K, 1 amp fuse and a control relay
with 250 VDC at 10 amp rated contacts across the battery pack. The relay is
used to open this voltage divider circuit when not needed.
The resistors are the aluminum body heat sink type RH style in the 50 watt
range. Just happen to have some of these in stock, so they are a little
larger than they need to be.
I tapped off between the 2k and 28k resistor which was about 15 volts to
drive a 0.01 amp 12 volt relay coil. When the battery pack voltage drops to
157 volts, I still have 12 volts off this circuit.
Roland
----- Original Message -----
From: "Neon John" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Friday, April 21, 2006 3:43 PM
Subject: Re: Albright Contactor rework
> On Fri, 21 Apr 2006 08:09:53 -0600, "Bill Dennis" <[EMAIL PROTECTED]>
> wrote:
>
> >Dang, I've got two of these wired into my EV already, wired with 48V. I
> >don't have the facilities or expertise to rewind them, either. I wonder
> >if
> >I should add a circuit to my KSI so that it won't all the contactors to
> >close until after the controller is precharged.
>
> All you need is a drill motor, a vice to clamp it in and some
> all-thread. The winding machine makes it easier but I've wound many a
> coil at my bench with nothing more than that. I'm going to put some
> photos on my website this weekend.
>
> About the KSI, I don't know. I'd certainly want to have someone close
> the contactors while I watched them. It may not be a problem, I just
> don't like to see high current contacts operate that slowly.
>
> I'm going to actually measure the motion on one because I have the
> stuff to do it but you can get a good idea of the closing speed if you
> have an o-scope and a current shunt. As the armature in the relay
> moves, it generates counter-emf and varies the reluctance of the
> magnetic circuit. Both oppose the build up of current. If you scope
> the current going to the coil, you'll see it start to build in the
> standard LR time-constant but as the armature starts moving, the
> current either levels off or actually decreases, depending on the
> design. When the armature slams home, the current continues to rise
> at the LR time constant. The actuation interval is quite obvious once
> you see the waveform.
>
> Interesting story about this phenomena in the nuclear plant. This
> current waveform is fairly well known among those dealing with
> electromagnetics but not generally known in the EE world. Inside the
> containment of Sequoyah NP are a couple of huge solenoid-operated
> valves. For a variety of reasons, mainly having to do with the
> extremely harsh environment (potentially 50 psi of steam, maybe 4-500
> deg F and potentially high radiation), instead of motor-operated
> valves, this application used huge solenoids. Several inches in
> diameter and over a foot long, operated on 250VDC.
>
> These valves were critical to the reactor's safety so there were two
> in series (hydraulically, not electrically.) The actual operation had
> to be verified periodically which involved either entering the
> containment and exposing workers to radiation or attaching an LVDT or
> similar transducer to the valve stem. The LVDT wasn't reliable and
> man-REMs are to be avoided whenever possible.
>
> We were noodling this over in the office one day. I'd just designed
> and had the shop build a hydraulic pulse generator. This thing would
> generate a 2200 psi square wave with a rise time of under 10ms. It
> used a special dual-coil solenoid valve that would open in about 1ms.
> One coil got a capacitor discharge into it to kick the plunger and the
> other coil was the holding coil. The coils were operating at the edge
> of the envelopes and I'd been measuring the speed using this current
> technique.
>
> Suddenly an idea dawned. I could verify those solenoid valves'
> operation without doing anything inside the containment. We grabbed a
> tech and hauled down to the instrument room, put a shunt in line,
> scoped it and had the control room operator cycle the valve a few
> times (during startup testing so the plant wasn't hot.) Viola!! The
> prettiest motion waveform one could ask for.
>
> Of course, in an NP, you don't just DO things, you have to kill a few
> trees first. Westinghouse and TVA Engineering Design had to get
> involved, do a bunch of analyses and a lot of testing - waveform vs
> actual motion and all that. But in the end, my procedure was adopted
> and AFIK is still in use. Those valves can be tested from the comfort
> of the air conditioned Aux Inst room.
>
> John
>
> >Y'all may remember the group purchase on the Albright SW200A-678
> >contactors with the 56 volt coils that was organized last year. I
> >bought 8 (and sure wish I'd bought more :-)
> >
> >I finally got time today to take the solenoid apart and compute the
> >new winding for 12 volt nominal service. Following is an excerpt from
> >my shop log book detailing the work.
> ---
> John De Armond
> See my website for my current email address
> http://www.johngsbbq.com
> Cleveland, Occupied TN
> Don't let your schooling interfere with your education-Mark Twain
>
>
--- End Message ---
--- Begin Message ---
At 03:06 PM 21/04/06 -0400, you wrote:
Steve,
On the 29 I'm be long distance racing my work truck 40 golf cart batteries
, for 3 hours and will be shooting for 135+ miles ( to beat that Rave EV )
I guess you don't have to worry too much about that. The longest I've ever
done is 132 miles. At 135+ miles,
G'day all
I had an .... intriguing conversation with someone yesterday. It's the time
of year for the Targa Tasmania road-rally again (annual event)
http://www.targa.org.au/ , a 2000km (1250 mile) or so road race, over 5
days, each day being 200 to 550kms (125 to 350 miles).
Question under discussion: what would it take to field a battery-electric
race car?
This person seemed genuine, understands racing sponsorship and understands
that ths would take an absolute mint of money so would need a top-notch
presentation to raise the sponsorship dollars. But is it doable? ProEV have
got around 120 miles on 70Ah I believe, and Kokam make 200Ah cells, so 340
miles at the same sort of voltage, 500kg of batteries. Take it up a bit
more, go to 650 or 700kg of batteries to get the race stages, and put it
all into a custom chassis, entirely designed around the battery. So, take
US$130,000 or so of battery, build a race car around it, or less than that
and charge from 415V 3-phase 30 amps for an hour in the middle of the day
to put enough back in to complete the stage. Or battery swap for a charged
pack carried in a support vehicle (since this would be a custom chassis,
the battery swapping system can be designed in).
Such a car would attract LOTS of attention, and would HAVE to perform
flawlessly.
Has anyone attempted or heard of a vehicle like this?
Thanks and regards
James
--- End Message ---
--- Begin Message ---
has anyone tried the what's up or doc watson monitor, as an
alternative to a link 10? http://www.rc-electronics-usa.com/ammeters/
rv-battery-monitor.html
I figure that I'd need to current divide, using appropriate low
value, high power resistors to send less than 100 amps to the unit.
also, is there a way to adapt a kill-a-watt from AC to DC easily?
thanks for info.
elaine
berkeley, CA
'76 citicar, converted '86 pickup truck
--- End Message ---
--- Begin Message ---
I saw your truck Mike. The racks are built for those bitty batteries. I
bet it wouldn't be to painfull to build new racks. LR.........
----- Original Message -----
From: "Mike Phillips" <[EMAIL PROTECTED]>
To: "Andre' Blanchard" <ev@listproc.sjsu.edu>
Sent: Friday, April 21, 2006 11:04 AM
Subject: Low rider floodie quest
Is there a floodie available that someone has tried that is not over
7" tall? My truck can only support 7" and shorter.
Mike
--- End Message ---
--- Begin Message ---
Thinking more about this, I realized there is no solid control over
how much power would get pulled from each string. The voltage
difference, sag, and amount of lead footed driving would determine how
much gets pulled from each.
If one drives really fast or lead foots it all the time, the Orbitals
would run down first, because of their smaller capacity. Drive real
slow, and the Orbitals might not get used much until the J150 string
is nearly empty.
Imagine 13 J150 and 11 Orbitals together. The bias would be even
stronger to pull from the J150 string. One could experiment and vary
the difference to tweak the bias to their typical driving style. The
idea being that the bulk would come from the lower cost per mile
Trojans. Of couse one would have to keep in mind that if the
difference is too great, the Trojans would discharge into the
Orbitals, possibly damaging them due to overcharge. And waste power.
Using 6 volt Trojans would give finer control over this.
It would be a good idea to have two separate e-meters to measure the
state of charge on each string. And the ability to switch off either
should one of them get to 80% DOD (or maybe 50% for the Orbitals since
they don't tolerate deep discharge as well).
Really thinking more about this- How about a motor controller that has
two power inputs, and two power stages with the outputs joined. It
could vary the amount pulled from each string in real time and "mix"
the outputs. The PWM inputs should be synced at the start of the PWM
cycle to properly buck, but the on times could be varied independently
depending on how much power you wanted to pull from each string. With
a setup like this, one could have equal voltage battery strings, but
easily vary the amount pulled from each. With some clever PWMing, one
could have widely varying pack voltages (PWM cycles start times not
synced, only one stage on at a time). Hmmm.. head hurting..
Brad Baylor
--- End Message ---
--- Begin Message ---
Bill,
In addition to this, know that the neon lamp is ~constant current
device when it breaks down (ignites) and the voltage on it is very low.
Resistor in series takes the slack. The ionized gas is conductive
and resistance of the lamp itself is far lower than that resistor.
So the resistor is picked such that it provides 1-2 mA into a short,
so the voltage on the lamp is pretty much ignored.
The same lamp will work just fine at 1,000V or 10,000V, it doesn't
see it ( it drops on the resistor) it only must see 1-2 mA through it.
HTH,
Victor
Tom Shay wrote:
A neon lamp lights when its voltage reaches about 60 volts. A 120V
rated neon lamp has a resistor in series to allow it to operate from a
120V source. It will be dimmer or brighter when the voltage is lowered
or raised from 120. Its life will be reduced at 160 volts unless the
series resistance is increased.
----- Original Message ----- From: "Bill Dennis" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Friday, April 21, 2006 8:22 AM
Subject: Neon (Lamp, not John) Questions
How do the voltage ratings on neon lamps work? If a lamps says that its
voltage rating is 120V, does this mean that it won't turn on until
120V, or
that it should never be connected to more than 120V?
If it means that the lamp won't turn on until 120V, then how firm is that
number? Will it be passing some current at 109V or 117V, but not be
passing
full current until 120V? Or will it be passing no current at all until
120V?
Finally, if it means that it won't turn on until 120V, then how do you
determine the upper range (e.g., with a 120V pack, will the lamp be
okay at
a fully-charged 160V)?
Thanks.
Bill Dennis
--- End Message ---
--- Begin Message ---
What if we did get those cheap,low power capacitive pickups. Could we
make a little external circuit to "condition" the signal to the hairball?
use the fan or a sheet metal disk.
ie 40 fan blades giving sharp pulses past a cap pickup of less than 10% duty
like so __|____|____|____... 40/rev
use a 555 timer triggered by a "divide by 10"
Perhaps use a 556 dual timer to get the pulses pre-treated for the
divide by 10 to minimize lost pulses
The reason I ask is because the original crank pully had such a sensor
and allows for belts nicely.
--- End Message ---
--- Begin Message ---
Lee Hart wrote:
Personally, I think they measure voltage because it is cheap and easy.
To measure actual state of charge, you'd need to watch current in/out of
the battery and accumulate amphours; or measure voltage and current and
infer state of charge from them by some empirical equation.
That's exactly right Lee. But the worst part is they are trying to
convince you that is all right method to get you to buy into it.
All fuel gauge chips (laptops, cell phones, camcorders) do it that way.
How accurate do you find them?
When I drop my cell phone, it's 4 bars charge level indicator is on
top bar in about 3 min, even though the battery is still near dead.
That is precisely because terminal voltage is used.
Ah count is proper method, but average consumer doesn't want to
pay for questionable benefits. I know my phone lasts for few days,
why bother with charge level bars?
EV battery doesn't last for days, this is why we use SOC meters,
(e-meter being most common device for now), not voltmeters.
As we just discussed in previous trend, you sure can use simple
voltmeter, (it's better than nothing), but you get what you paid for...
Victor
--- End Message ---
--- Begin Message ---
My original idea when I bought the 2 56V contactors was to connect each one
across half the traction pack. My fully-charged voltage is 150V, so 75V
seemed too high to drive the 56V coil, and I would have needed to put a
resistor in series with the coil to lower the voltage.
Since these contactors are guaranteed to pull in down to 37V, I got a 48V
power supply which I connected to the traction pack for input and to the
coils on output. I thought I was all set, until Neon John posted his data
about the contactors pulling in too slowly.
Bill Dennis
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Roland Wiench
Sent: Friday, April 21, 2006 4:40 PM
To: ev@listproc.sjsu.edu
Subject: Re: Albright Contactor rework
Hello All,
How about using a voltage divider across your battery pack to get the
voltage you need.
On my 180 volt pack, I install a 2k, 28K, 1 amp fuse and a control relay
with 250 VDC at 10 amp rated contacts across the battery pack. The relay is
used to open this voltage divider circuit when not needed.
The resistors are the aluminum body heat sink type RH style in the 50 watt
range. Just happen to have some of these in stock, so they are a little
larger than they need to be.
I tapped off between the 2k and 28k resistor which was about 15 volts to
drive a 0.01 amp 12 volt relay coil. When the battery pack voltage drops to
157 volts, I still have 12 volts off this circuit.
Roland
----- Original Message -----
From: "Neon John" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Friday, April 21, 2006 3:43 PM
Subject: Re: Albright Contactor rework
> On Fri, 21 Apr 2006 08:09:53 -0600, "Bill Dennis" <[EMAIL PROTECTED]>
> wrote:
>
> >Dang, I've got two of these wired into my EV already, wired with 48V. I
> >don't have the facilities or expertise to rewind them, either. I wonder
> >if
> >I should add a circuit to my KSI so that it won't all the contactors to
> >close until after the controller is precharged.
>
> All you need is a drill motor, a vice to clamp it in and some
> all-thread. The winding machine makes it easier but I've wound many a
> coil at my bench with nothing more than that. I'm going to put some
> photos on my website this weekend.
>
> About the KSI, I don't know. I'd certainly want to have someone close
> the contactors while I watched them. It may not be a problem, I just
> don't like to see high current contacts operate that slowly.
>
> I'm going to actually measure the motion on one because I have the
> stuff to do it but you can get a good idea of the closing speed if you
> have an o-scope and a current shunt. As the armature in the relay
> moves, it generates counter-emf and varies the reluctance of the
> magnetic circuit. Both oppose the build up of current. If you scope
> the current going to the coil, you'll see it start to build in the
> standard LR time-constant but as the armature starts moving, the
> current either levels off or actually decreases, depending on the
> design. When the armature slams home, the current continues to rise
> at the LR time constant. The actuation interval is quite obvious once
> you see the waveform.
>
> Interesting story about this phenomena in the nuclear plant. This
> current waveform is fairly well known among those dealing with
> electromagnetics but not generally known in the EE world. Inside the
> containment of Sequoyah NP are a couple of huge solenoid-operated
> valves. For a variety of reasons, mainly having to do with the
> extremely harsh environment (potentially 50 psi of steam, maybe 4-500
> deg F and potentially high radiation), instead of motor-operated
> valves, this application used huge solenoids. Several inches in
> diameter and over a foot long, operated on 250VDC.
>
> These valves were critical to the reactor's safety so there were two
> in series (hydraulically, not electrically.) The actual operation had
> to be verified periodically which involved either entering the
> containment and exposing workers to radiation or attaching an LVDT or
> similar transducer to the valve stem. The LVDT wasn't reliable and
> man-REMs are to be avoided whenever possible.
>
> We were noodling this over in the office one day. I'd just designed
> and had the shop build a hydraulic pulse generator. This thing would
> generate a 2200 psi square wave with a rise time of under 10ms. It
> used a special dual-coil solenoid valve that would open in about 1ms.
> One coil got a capacitor discharge into it to kick the plunger and the
> other coil was the holding coil. The coils were operating at the edge
> of the envelopes and I'd been measuring the speed using this current
> technique.
>
> Suddenly an idea dawned. I could verify those solenoid valves'
> operation without doing anything inside the containment. We grabbed a
> tech and hauled down to the instrument room, put a shunt in line,
> scoped it and had the control room operator cycle the valve a few
> times (during startup testing so the plant wasn't hot.) Viola!! The
> prettiest motion waveform one could ask for.
>
> Of course, in an NP, you don't just DO things, you have to kill a few
> trees first. Westinghouse and TVA Engineering Design had to get
> involved, do a bunch of analyses and a lot of testing - waveform vs
> actual motion and all that. But in the end, my procedure was adopted
> and AFIK is still in use. Those valves can be tested from the comfort
> of the air conditioned Aux Inst room.
>
> John
>
> >Y'all may remember the group purchase on the Albright SW200A-678
> >contactors with the 56 volt coils that was organized last year. I
> >bought 8 (and sure wish I'd bought more :-)
> >
> >I finally got time today to take the solenoid apart and compute the
> >new winding for 12 volt nominal service. Following is an excerpt from
> >my shop log book detailing the work.
> ---
> John De Armond
> See my website for my current email address
> http://www.johngsbbq.com
> Cleveland, Occupied TN
> Don't let your schooling interfere with your education-Mark Twain
>
>
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Simple common rule here: energy supplying half of a connector
is always female and energy receiving half - always male.
That way no energized parts are exposed.
Victor
Nick Austin wrote:
Public service announcement:
Never make an extension cord with two male ends!
If you plug one male end into the outlet, then you have live conductors
sitting on the other side ready to shock you!
Make a male inlet, and connect the female end of an extension cord into that.
Thanks!
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Eco-friendly car goes to the extreme
Panasonic has created a car that runs off… wait for it… two AA batteries!
AA battery car
We love Mother Nature as much as the next fella, but surely Panasonic’s
new electric concept car that runs off two AA batteries is tree-hugging
to the extreme. Next they’ll be coming up with a car that converts the
heat from your buttocks into raw horsepower (hold on a sec, we’re
calling the Patent Office). This isn’t a joke - the two AA battery
thing, that is. Panasonic’s OxyRide car weighs under 20kg and can carry
a passenger about a mile before running out of juice. Well, at least
it’d get you to the shops and back!
It’s highly unlikely that we’ll all be zipping around in
AA-battery-powered cars though, because this was really just an
elaborate stunt by Panasonic to showcase its new range of Digital Xtreme
Power AA batteries. Nonetheless, stunt or no stunt, it’s pretty impressive.
Link:
http://www.t3.co.uk/news/247/general/general/eco-friendly_car_goes_to_the_extreme
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elaine chiu wrote:
> has anyone tried the what's up or doc watson monitor, as an
> alternative to a link 10? http://www.rc-electronics-usa.com/ammeters/
> rv-battery-monitor.html
This is the first I've seen it mentioned on the EV list.
> also, is there a way to adapt a kill-a-watt from AC to DC easily?
Possibly; I have one but don't know if it works on DC, or what would be
needed to make it do so.
--
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
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James,
James Massey wrote:
Such a car would attract LOTS of attention, and would HAVE to perform
flawlessly.
Lots of attention is good but still don't pay bills.
Has anyone attempted or heard of a vehicle like this?
If you get sponsorship, my company will attempt, I don't see
*any* technical problems. All doable today.
If it has to be done in AU, can be arranged too. It won't be
cheap (may or may not fit in 130k) but will perform as
flawlessly as hardware manufacturers guarantee their hardware.
Problem is to get sponsorship *in order to* build it, not the
other way around. A secured guarantee to get paid from sponsors
after race is OK too (will allow to borrow money needed to build).
Classic issue...
Victor
Thanks and regards
James
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OT?
This is a PT Cruiser based plug-in hybrid with lithium batteries that
goes 150 mi. before the engine clicks in, looks the ICE would hardly
ever be used in normal driving:
http://www.hybridtechnologies.com/media.php
--
Paul Wujek ([EMAIL PROTECTED])
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I'll believe it when I see it. That company releases press releases
all the time and never delivers the goods.
Here is a prime example:
http://www.hybridtechnologies.com/media.php?mediaID=040831
Also, in that drop down box at the top of the page, look at that long
list. Have they ever actually built anything?
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Now load it up with even more AA's and make it really scoot!
----
Someone at school had a SWR meter/analyzer that used 10 AA batteries.
The battery box claims they are 1.5v each. Connected in series, the
device was claiming 16.1v. I was thinking my car battery at 12 and
these 10 little batteries at 16... pretty neat. I wondered what is
the highest series voltage that has ever been configured using AA's?
----
Bonus story!
We had this cart with a fully working demonstration air conditioning
unit on it. It required 28 volts DC to be hooked up to it to drive
the motor to drive the compressor. The unit was low on freon so the
(can't think of the name) switch wouldn't let the compressor run. The
instructor wanted to bypass it to see if the motor still worked... He
got a good sized wire and connected it to the hot side of the solenoid
and touched it to the motor terminal.. It audibly arced and I felt he
was lucky that it didn't weld the wire to the motor post. It did
leave a melt mark on the post and the end of the wire. The motor
plate said 90 amps.
I would have had the power turned off, connected the wire and then
used the switch on the cart to avoid doing what he did...
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I went to go get a license plate frame made for my EV and it was a
little too much driving around. I recently programmed the low voltage
battery limit to 250V on a 288V nominal (24 orbitals) pack. I am
thinking this is to conservative for two reasons.
I didn't light even one red led on the regs, this feture on the zilla is
very smooth and effective. It felt like the battery was gone, but
obviously not. I just needed a few short duration dips below that to get
home at speed. Instead of an embarrassing crawl at 20-25mph for the last
one block.
What is a good setting for this?
As I said, 24 orbitals, 3000lb before conversion, Zilla1K HV, 9 incher.
I am thinking that a dash mounted valet switch and a second set of
settings may be in orde, although I try to avoid such deep discharges, i
need to be able to over-ride and get out of my own way.
For those interested, I had these ideas for my license plate frames.
if you can read this
it is time to plug me in
You've just been passed <<<<< I chose this one
by an electric car <<<<< something for people to think
about at the stoplight.
Warning this car has
lots of potential
Happiness is 1000#
of warm lead
I've got lead poisoning
no smog, no oil changes
no gas, no problem
Would you still drive it
if exhaust came out the dash?
Hybrids? Hybrids? we don't
need no stinking hybrids
It's electric
Driver carries no gas
Resistance is useless
This car has lotsa potential
Resistance is useless
But fun to overcome
It takes ~12kwh to refine <<<they couldn't get the ~ or the word
"about"
a gallon of gas. Why bother? <<< it came out looking like a negative
number
28 Horsepower
wanna race?
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How important,significant is aero drag in an EV ?...
Cyclists say "Aerodynamic drag represents the largest resistance while
riding over level ground"
What is "knee point" ?
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First off, the 2K resistor is un-necessary and wastes energy. The
resistance of the relay coil can serve as the lower leg of the voltage
divider. Additionally, the upper resistor can be larger since it no
longer needs to feed two loads (the lower resistor and the relay
coil), saving an additional increment of power and heat.
There aren't too many relays out there that will pull in with 10 ma
through the coil. With more typical relay coil currents up in the 100
ma or more range and with power dissipation rising as the square of
current, one can very quickly end up with a range wasting, heat
generating heating element.
Even if the watt-hours used doesn't affect the range much, wasting
power and generating heat like this just offends my thrifty
engineering sensibilities. That's why I'll go to extra effort not to
use dropping resistors. A little 250ma DC/DC converter doesn't cost
any more than those "Goldie" power resistors you described, yet
dissipates almost no heat. If I didn't already have a DC/DC converter
for the 12 volt aux systems, I'd have no problem at all
double-sided-taping or cable-tieing a little converter to each relay
or contactor. I STILL use the peak/hold circuit whenever I can
because it generates enough force to overcome stiction, dirt in the
armature and other gremlins while generating minimal heat in the coil,
extending its life.
Not that it bothers others that much to be so wasteful. The standard
method of driving 28 volt status lights in power plants from the 250
VDC buss is with a big honking resistor on the back of each socket.
And, of course, sufficient fans to keep the control board internals
cool.
John
On Fri, 21 Apr 2006 17:40:27 -0600, "Roland Wiench" <[EMAIL PROTECTED]>
wrote:
>Hello All,
>
>How about using a voltage divider across your battery pack to get the
>voltage you need.
>
>On my 180 volt pack, I install a 2k, 28K, 1 amp fuse and a control relay
>with 250 VDC at 10 amp rated contacts across the battery pack. The relay is
>used to open this voltage divider circuit when not needed.
>
>The resistors are the aluminum body heat sink type RH style in the 50 watt
>range. Just happen to have some of these in stock, so they are a little
>larger than they need to be.
>
>I tapped off between the 2k and 28k resistor which was about 15 volts to
>drive a 0.01 amp 12 volt relay coil. When the battery pack voltage drops to
>157 volts, I still have 12 volts off this circuit.
---
John De Armond
See my website for my current email address
http://www.johngsbbq.com
Cleveland, Occupied TN
Don't let your schooling interfere with your education-Mark Twain
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On Fri, 21 Apr 2006 19:08:08 -0600, "Bill Dennis" <[EMAIL PROTECTED]>
wrote:
>My original idea when I bought the 2 56V contactors was to connect each one
>across half the traction pack. My fully-charged voltage is 150V, so 75V
>seemed too high to drive the 56V coil, and I would have needed to put a
>resistor in series with the coil to lower the voltage.
>
>Since these contactors are guaranteed to pull in down to 37V, I got a 48V
>power supply which I connected to the traction pack for input and to the
>coils on output. I thought I was all set, until Neon John posted his data
>about the contactors pulling in too slowly.
This is an excellent situation for a peak/hold off the 75 volt pack
half. Depending on how bumpy your terrain is, only 10-20% of the
rated current is necessary to hold the contactor in once it is
actuated. A resistor shunted by a capacitor will do the trick. Figure
the resistor for maybe 25-50 ma since the coil pulls 225ma at 51
volts.
The coil resistance is about 200 ohms. For 0.050 amps at 75 volts,
the total resistance should be 1500 ohms. Subtract the 200 ohms coil
resistance and your dropping resistance becomes 1300 ohms. power
dissipation = .050^2 * 1300 = 3.25 watts. A 5 watt sand resistor will
do the job.
For a 0.25 second time constant, shunt the resistor with:
0.25 = 1300C
C = 192uF.
I'd probably go up to 220uF, a standard value. I'd use a 50 volt part
for plenty of margin.
This setup will give the solenoid a little less than a half second
kick and then drop the current down to the holding level. As
important if you hook the main contactors up to the throttle
microswitch, the cap will discharge and the peak/hold circuit will be
ready for the next actuation in about another half-second. That's
plenty fast enough.
John
---
John De Armond
See my website for my current email address
http://www.johngsbbq.com
Cleveland, Occupied TN
Don't let your schooling interfere with your education-Mark Twain
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On Fri, 21 Apr 2006 18:12:54 -0700, Victor Tikhonov
<[EMAIL PROTECTED]> wrote:
>Lee Hart wrote:
>>
>> Personally, I think they measure voltage because it is cheap and easy.
>>
>> To measure actual state of charge, you'd need to watch current in/out of
>> the battery and accumulate amphours; or measure voltage and current and
>> infer state of charge from them by some empirical equation.
>
>That's exactly right Lee. But the worst part is they are trying to
>convince you that is all right method to get you to buy into it.
>
>All fuel gauge chips (laptops, cell phones, camcorders) do it that way.
>How accurate do you find them?
No they don't.
>
>When I drop my cell phone, it's 4 bars charge level indicator is on
>top bar in about 3 min, even though the battery is still near dead.
>That is precisely because terminal voltage is used.
Well, maybe your cheap-sh*t phone does - after all, you get what you
pay for - but most other phones don't.
>
>Ah count is proper method, but average consumer doesn't want to
>pay for questionable benefits. I know my phone lasts for few days,
>why bother with charge level bars?
Because it matters both to the user and to the battery charging
circuit if long life (which enables long warranties) is desired, which
it is.
The Maxim/Dallas DS1922/DS1923 Battery Gas Gauge chip is rather
ubiquitous because it works, because it can work with one additional
lead and because it's dirt-cheap. Here's an app note that will show
you how it's done.
http://www.maxim-ic.com/appnotes.cfm/appnote_number/3761
Larger batteries like those in laptops have this chip or something
similar embedded in the pack. Cellphone batteries are generally too
small for that and since it isn't expected that the customer will be
changing batteries frequently, the chip or in some instances the
algorithm implemented in the processor, is in the phone.
When you drop your phone and break contact, then re-establish contact,
the chip no longer knows the battery's SOC because that might not be
the same battery as before. It's reasonable to assume since the
device is receiving power and the voltage is high enough, that the
battery is charged, thus the full scale indication. If that is
incorrect, then the two can be re-synched during the next charge
cycle. Ultimately the world doesn't come to an end if the gas gauge
is a little off after such an insult to the system as dropping the
phone.
My phone will fully charge its battery in just a couple hours but it
takes most of the night to sync the gas gauge, probably because the
charging circuit relies on a long, low magnitude charge current to
bring the battery up to full charge safely.
My laptop batteries, each of which contains a gas gauge chip, stay
well-synched even when the batteries are changed out between
chargings. When the on-screen gas gauge says that it is down to 10%,
it's time to be saving all work and shutting down.
Dell's battery FAQ addresses the out-of-sync problem with instructions
to let the laptop run the battery all the way down until it shuts off,
then fully charge the battery. That always brings the gauge back in
sync.
I don't know which is worse, Vic, your crude stereotyping of people or
your apparent lack of knowledge on how consumer battery gas gauges
work. Doesn't bode well for that killer E-meter replacement you keep
promising......
John
---
John De Armond
See my website for my current email address
http://www.johngsbbq.com
Cleveland, Occupied TN
Don't let your schooling interfere with your education-Mark Twain
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