EV Digest 4619
Topics covered in this issue include:
1) Re: e-meter type gadget wish list wanted.
by Ryan Stotts <[EMAIL PROTECTED]>
2) Re: e-meter type gadget wish list wanted.
by Rush <[EMAIL PROTECTED]>
3) Re: Power Steering
by "Tom Shay" <[EMAIL PROTECTED]>
4) Re: Russco vs Zivan vs PFC
by Lee Hart <[EMAIL PROTECTED]>
5) Re: e-meter type gadget wish list wanted.
by Lee Hart <[EMAIL PROTECTED]>
6) Re: Correct AGM finish charge (Was: Re: PFC-30)
by Lee Hart <[EMAIL PROTECTED]>
7) Re: Alternative batteries
by Lee Hart <[EMAIL PROTECTED]>
8) Re: Buck controller for little motors
by Lee Hart <[EMAIL PROTECTED]>
9) RE: Power Steering
by "Don Cameron" <[EMAIL PROTECTED]>
10) RE: PFC Ground and Pack Negative (was RE: Russco vs Zivan vs PF)
by "Don Cameron" <[EMAIL PROTECTED]>
11) Re: Power Steering
by Seth Allen <[EMAIL PROTECTED]>
12) Re: e-meter type gadget wish list wanted.
by Michael Hurley <[EMAIL PROTECTED]>
13) Re: Alternative batteries
by Ryan Stotts <[EMAIL PROTECTED]>
14) Re: e-meter type gadget wish list wanted.
by Rod Hower <[EMAIL PROTECTED]>
15) Re: e-meter type gadget wish list wanted.
by Mark Farver <[EMAIL PROTECTED]>
16) Re: e-meter type gadget wish list wanted.
by Victor Tikhonov <[EMAIL PROTECTED]>
17) Re: e-meter type gadget wish list wanted.
by Danny Miller <[EMAIL PROTECTED]>
18) Re: Power Steering
by "STEVE CLUNN" <[EMAIL PROTECTED]>
19) Re: Power Steering
by Ryan Stotts <[EMAIL PROTECTED]>
--- Begin Message ---
Victor Tikhonov wrote:
> > The ability to be interfaced with the speedometer/odometer pulse signal
> > to then display miles remaining at current state of charge at current
> > rate of discharge.
> Done. What kind of speed sensors these are? Do speedometrers send out
> 12V pulses?
A little bit of info on the speedometer sender unit:
http://www.autometer.com/download_instruction/616A.pdf
--- End Message ---
--- Begin Message ---
Victor,
If you don't already know about 1-wire devices by Dallas Semiconductor, you
might want to check them out.
"1-Wire® devices lower system cost and simplify design with an interface
protocol that supplies control, signaling, and power over a single-wire
connection. A variety of identification, sensor, control, and memory functions
are available in traditional IC packages, ultra-small CSPs, and
stainless-steel-clad iButtons®. "
at http://www.maxim-ic.com/1-Wire.cfm
I know of them from a Radiant Heating monitoring application at
http://www.ourcoolhouse.com/monitor/monitor.htm and his software/hardware page
http://www.ourcoolhouse.com/scada.htm. I would have paid for a monitoring
system like that when I poured my shop slab.
They are also used in weather stations for temp, wind speed, humidity, solar
radiation etc.
There are also V sensors, but used in cellphones, so I don't know if they can
be used for HV applications.
Rush
Tucson AZ
www.ironandwood.org
--- End Message ---
--- Begin Message ---
Vehicles with power steering are hard to steer with the power off because
the gear box or rack-and-pinion has a different gear ratio than a manual
steering unit. For example, on my 1983 Ranger pickup, the manual box
required almost six turns of the wheel from lock-to-lock compared to
3 1/2 turns for a power steering box. As you'd expect, the power steering
was quite hard to steer when the truck was not moving and the pump was
turned off. When the truck was moving, steering effort was moderate.
I had a seperate motor for driving the power steering pump and turned it off
when I didn't need it to conserve battery energy and because the pump-motor
setup was noisy.
----- Original Message -----
From: "Nick Austin" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, August 23, 2005 3:18 PM
Subject: Re: Power Steering
On Tue, Aug 23, 2005 at 06:13:51PM -0400, Cwarman wrote:
I dont see much mention of power steering pump when doing a conversion.
I have a 1997 Chevy S10 im tonight pulling the engine out and i left
that portion on for now because wasnt sure if thats something ill need
or not. Im under the impression that a vehicle made for powersteering
but is unistalled or off turns WAY harder than a truck that is made
without powersteering, is this true ? Any suggestions ?
CWarman
One option to consider is electric power steering, this fits in well with
an EV :)
http://www.nsxprime.com/FAQ/Technical/eps.htm
--- End Message ---
--- Begin Message ---
Ryan Stotts wrote:
> Similar to some cars with certain tires and/or seats that cause static
> build up and when one stands on the ground and touches the door and
> gets shocked?
Yes; except this isn't a harmless momentary static electric shock. This
is a continuous current that can be high enough to kill you.
> Ok, so the charger is now wired to the car body as per the
> instructions, so the car body is using that "earth ground/third
> prong" in the wall outlet, and if there is a voltage leak, it
> will handle it and not me when I go to open the door?
Correct. The fault current goes to ground via the 3rd safety ground
wire, not through you!
> Now what is the difference between the current model of "unisolated"
> chargers and the model that might be released that is supposedly
> isolated? How are the two chargers different? How will they be
> installed differently?
A non-isolated charger (K&W, Russco, PFC-xx) has a direct path from the
AC powerline to its DC output. So if you touch one of its outputs (i.e.
any battery terminal) and ground, you get a shock. If your skin
resistance is low enough, you die!
You can prevent this by plugging such a charger into a GFCI-protected
outlet. The GFCI measures the leakage current to ground, and if it
exceeds about 5ma (0.005 amps) it shuts off the AC power. 5ma is enough
to give you a nasty shock, and make you jump convulsively; but it's not
enough to kill a normal healthy person.
> So when I have the charger cranked to be pulling 49 or 50 amps from
> my 50 amp breaker, am I going to be getting "nuisance trips" because
> of the GFCI? Do they even make an outlet for that amperage?
The trouble is, there can be lots of reasons for a leakage path to
ground besides a person touching a battery terminal and ground. The tops
of the batteries could be wet or dirty, or there could be carbon dust in
the motor, or your controller, DC/DC, heater, etc. have capacitors or
other parts to ground. These can cause the GFCI to trip even if you
aren't touching anything. At it worst, these "nuisance trips" will
prevent you from charging at all.
This is why an isolated charger is preferred. Under normal conditions
(with no faults in your wiring), you can touch ground and any battery
terminal while charging and won't get a shock. In fact, a dead short
between any battery terminal and ground will do nothing.
> It's been said time and time again on this list "don't work on the
> pack while it's being charged". I'll defiantly not work on the car
> while it's plugged into the wall.
Good! Doing this is just asking for trouble! Even if you *do* have an
isolated charger, you can still have wet or dirty batteries etc. that
have connected some point in your pack to ground. When you touch another
point in the pack and ground, you get a shock due to the voltage
difference between these two.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Victor wrote:
>> Can owners tell me what they don't like about their e-meter,
>> how you'd rather see it designed or operated?
Ryan Stotts replied:
> I don't own one yet either, but from all I've read about it, it
> seems like a finicky, fickle, delicate device. It's also somewhat
> expensive. Just how accurate is it anyways?
The E-meter/Link-10 actually *is* a pretty robust and accurate device.
It is certainly a lot better than your typical cheap digital multimeter!
That's why it is relatively expensive. I think the designers of would-be
replacements will have their hands full getting something to work as
well in the presence of the huge amounts of noise in an EV and over the
automotive temperature range.
I think its "reliability" problems are mainly operator miswiring errors.
Remember that it was designed for 12v systems. Its power, voltage sense,
and current sense inputs can easily withstand anything you can do to it
at 12v. But we wire them into high-voltage EVs -- and accidentally
connect the 50mv current sense leads to a 300v pack! No wonder it dies.
To fix this sort of problem, a new design is needed. Rather than depend
on external "band-aid" fixes like the voltage prescaler, DC/DC power
supply, and fuses to protect a 12v meter in a 300v system, it needs to
be a design requirement right up front that "no miswiring in a 500v
system will cause any harm."
I like the 2" round form factor; it's easy to cut a round hole in a dash
to mount it. But I'd prefer that it mount from the front (perhaps with
spring clips on the sides), so you don't have to fish around behind the
panel with the mounting ring.
Als, it should have a connector on the back to connect the wires; not
that fiddly screw terminal block. Yes, I know they wanted screw terminal
so Joe Idiot could wire it with nothing but his swiss army knife. But
they could have used screw terminals on some standard centers so we
could screw a pin header into it, and then plug a Molex or other
connector onto them.
The LED display is ok, but dated. It makes it draw way too much power. I
want a display that is readable at night, in direct sunlight, has a wide
viewing angle, and is large enough to read easily. Modern LEDs can do
this; old ones cannot. LCDs are a (cheap) possibility, but usually have
low contrast and are harder to read under adverse conditions.
I'd eliminate the separate 12 supply, and power it directly from the HV
pack. That requires a reasonably efficient wide-range DC/DC; but that's
do-able nowdays.
Of course it should have an isolated data port; RS-232 or whatever. But
I object to screwy proprietary formats. Give me plain ASCII, not CANbus
or SecretBus.
I think I would prefer a 2-box approach; one box contains all the
high-voltage stuff; shunt, amplifier, prescaler, power supply, and A/D.
This box is equivalent to two ordinary digital multimeters with serial
output; they just send the current and voltage data. The other box is
the display, operator controls, and serial port (and probably the
"brains" to make it work). It integrates this data to give you amphours,
average voltage, state of charge, or whatever.
As for *what* it displays... The E-meter's volts/amps/amphours/time
display is ok for engineers, but useless for the daily driver. The 5-LED
bargraph is just barely adequate as a "fuel" gauge. Probably its best
use for the casual driver is to set the 7-segment display to show "Time
Remaining (minutes at present load current)" or "SOC (0-100%)".
To me, the basic 7-seg display is adequate (save the fancy 9" VGA color
graphic display for the few who want to pay for it). But I would use a
10-bar bargraph for a higher resolution "fuel" gauge. Having it output a
signal to drive a normal car's gas gauge is clever, but I suspect it
will be a difficult problem due to the large differences between cars.
But, I would like a way for the equations that actually decide what gets
displayed to be downloadable. Think of the display head like a
programmable calculator; it accepts data from the volts/amps box, time
from its internal clock, and calculates whatever you want (average
voltage, amphours, Peukert corrected amphours, etc.).
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Lots of great information in this thread! I especially liked Bill Dube's
"Battleship" analogy.
Ryan Stotts wrote:
> We need an absolute end all, be all algorithm to get maximum life from
> our AGM's.
The problem is, even if we knew what this algorithm was, no one would
follow it! It would cost too much, or get in the way of other
priorities.
Here's an example closer to home: We all know what *we* should do to
live the longest possible life (eat right, exercise, don't smoke,
control your weight, avoid pollution and dangerous situations, etc.).
But we don't do that, either! Human nature...
> Is this absolutely going to require the purchase of regs?
No. Regs are just one tool to accomplish it. You could also use "smart"
modular chargers, or a battery balancing system that transfers charge
between batteries, or swap batteries to keep a matched set, or use a
battery type that tolerates imbalances better.
Like the "Battleship" game, the best charging strategy is *not* to
blindly follow some fixed sequence (i.e. always call A1, B2, C3, etc.
until you get to the opposite corner). Instead, you need an adaptive
strategy that watches the results, and gets modified accordingly (call
A1, B2, C3 etc until you get a "hit"; then call squares immediately
up/down/left/right of the hit).
A stupid charger blindly follows the same algorithm no matter how the
battery responds. The smarter the charger, the more it monitors and
adapts to the battery's actual condition.
If you really want to find the correct algorithm, then use your battery
pack like a "Battleship" game. Try different charging strategies on
different batteries. Monitor their individual performance, and look for
"hits" and "misses". Some strategies will clearly not work as well; the
batteries will be undercharging (too low a voltage, or low capacity) or
overcharging (higher voltage, getting hotter, gassing, venting). Have
several batteries using each method, so you can tell if a difference is
due to your charging method or from intrinsic variations between
batteries.
As the pack ages, regular checks will tell you which system seems to be
providing the longest life. Like drug trials, you can discontinue any
system that is clearly inferior before it murders the patient (for
instance, your "control" group with no regulation of any kind is likely
to be a killer).
What you'll find is that different EVs will have different "winning"
strategies, due to different driving patterns, different battery types.
There is no "perfect" charging algorithm that is always right.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Lee Hart wrote:
>> flooded lead-acids last about 1/3 as long as nicads; but are
>> 6:1 cheaper. This means they beat even nicads in cost per mile.
Victor Tikhonov wrote:
> I believe this statement needs clarification.
> When you say "last" do you mean calendar life or miles?
Fair enough; I was assuming a "commuter" EV that is driven about 30
miles/day which is 10k miles/year. Flooded lead-acid golf cart batteries
would last about 2 years or 20k miles per set. 20 batteries at $50 each
is (20 x $50) / 20k = $0.05/mile.
Flooded nicads would last about 100k miles or 10 years in the same
service, or 5 times longer. But the nicads cost 6 times as much ($300),
so your battery cost is (20 x $300) / 100k = $0.06/mile. Thus, the
floodeds have the lower cost per mile.
Now, if you drive a lot less than this (say 1k miles/year), the floodeds
would die of old age rather than cycle life. You'd need a new set after
5 years or 5k miles. Your cost is (20 x $50) / 5k = $0.20/mile.
In contrast, the nicads could last 20 years or 40k miles at this rate.
Their cost is (20 x $300) / 40k = $0.15/mile. Now the nicads are less
expensive.
You might also have decided to use more expensive lead-acids like AGMs,
or gotten a bargain on used nicads; these would tip the scales in favor
of nicads.
Or, a new EV owner might murder his/her first pack from ignorance or
abuse; in that case the cheaper batteries the better.
> But most people, realizing that, don't have (or not willing to
> spend) money for 10 at once, so buying one [flooded battery pack],
> then one more, one more, etc. Same as most of us pay monthly
> for homes way overpaying at the end.
I think I understand. Few people want to spend $10,000 for batteries and
charge "up front", especially when they don't know how their EV will
actually work out, or how long their interest in EVs will last. So they
buy cheap batteries and a cheap charger, even when they know that will
cost them more in the long run.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Chris Zach wrote:
> My Elec-trak is now powered by 30 40ah NiCDs. Which is great, however
> running taps on the pack is a bad idea. I have a number of 18 volt
> appliances that I want to run off the tractor power supply.
>
> The question is how do I step 36 volts down to 18 volts DC? I could go
> with a DC-DC converter, but I need something that can peak at around
> 20-40 amps at 18 volts. I could go with a 36 volt motor turning an 18
> volt motor; that's one possibility.
>
> Could I just use a Curtis controller somehow?
What sort of "appliances" are you running? If motors and lights, then
sure; a Curtis or any other small motor controller would be perfect. If
the load requires smooth regulated 18v, then you'd need something with a
filtered DC output, like an electronic DC/DC converter.
You probably don't need an isolated output, right? So if you use a DC/DC
converter, it doesn't really need to be 36v in, 18v out at 40amps.
Instead, you can use an isolated 18v in / 18v out 20amp converter. Power
it from the upper 18v half of the 36v pack. Its output is wired in
parallel with the lower 18v of the pack. Thus half the load current
comes directly from the lower batteries, and the other half from the
DC/DC. This way you only need a 18v x 20a = 360w peak converter.
In fact, if your average 18v load is low, then you could use a DC/DC
just big enough for the average load. The peak 18v load is supplied by
the lower 18v half of the pack, and then recharged during the light-load
times by the DC/DC.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
I think the pump was about $200 from MazToy Auto Recyclers in Portland (I
think you can find them cheaper). I needed to have a few hoses made for
about $70. The hoses mated it to the VW rack. I used an existing 100Amp
relay from the Beetle to turn on the pump when ignition was turned on. I
used the VW power steering reservoir and added a cooler rather than all that
crazy tubing.
Check the archives for "MR2", you will see lots of postings from Sheer, Ryan
and others about their use of the MR2 pump.
Don
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Cwarman
Sent: August 23, 2005 4:16 PM
To: ev@listproc.sjsu.edu
Subject: Re: Power Steering
Hey Don,
How much was the Toyota MR2 power steering pump ? Or did you find one at a
junk yard ? And this Mr2 pump completely replaced everything from your
original pump setup. Ive started to tear down the S10 today and i wasnt
sure about the powersteering pump so i didnt disconnect entirely and left it
under the hood.
Thanks
Cwarman
Don Cameron wrote:
>Few options:
>
>1. go without and use skinnier tires, more inflation and a bigger
>steering wheel.
>
>2. use the tailshaft (if exists) of the drive motor to power a pump,
>this does not help when at a stoplight though, as the drive motor is
stopped.
>Somewhat common.
>
>3. use an automatic transmission, and then the drive motor will always run.
>Use the drive motor to drive the pump. Randy at CanEV did this for a
>customer who wanted an automatic transmission.
>
>4. use a separate motor to power a hydraulic pump. Somewhat common.
>
>5. use an electric power steering rack. These can be from scrapped
>cars
>(NSX) or ordered from Europe. May require extensive modification.
>Very rare (if at all?)
>
>6. use a electro-hydraulic power steering pump from a Toyota MR2. A
>number of the AC systems use this option. This is what I use on the New
>Beetle and works just great.
>
>Don
>
>
>
>
>Victoria, BC, Canada
>
>See the New Beetle EV Conversion Web Site at
>www.cameronsoftware.com/ev/
>
>-----Original Message-----
>From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
>Behalf Of Cwarman
>Sent: August 23, 2005 3:14 PM
>To: ev@listproc.sjsu.edu
>Subject: Power Steering
>
>I dont see much mention of power steering pump when doing a conversion.
>I have a 1997 Chevy S10 im tonight pulling the engine out and i left
>that portion on for now because wasnt sure if thats something ill need
>or not. Im under the impression that a vehicle made for powersteering
>but is unistalled or off turns WAY harder than a truck that is made
>without powersteering, is this true ? Any suggestions ?
>
>CWarman
>
>
>
>>
>>
>>
>>
>
>
>.
>
>
>
--- End Message ---
--- Begin Message ---
Rich, I will give you a call with meter in hand (hopefully you will have
time). We did this a few months back. Something is not right - but we will
get it solved.
Don
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Rich Rudman
Sent: August 23, 2005 4:51 PM
To: ev@listproc.sjsu.edu
Subject: Re: PFC Ground and Pack Negative (was RE: Russco vs Zivan vs PF)
Don...
If the pack Neg and the Car chassis ARE connected... with a solid
connection...ie a SHORT the charger would blow up instantly.
So this is not happening... You have a leak or some kind of induced voltage
coupling into your chassis.
OR no real earth ground back to your outlet.
What I want in a leaky enviroment is the charger case insulated from the Car
chassis, But VERY solidly plug bonded to AC ground and earth, using the
Green wire in the AC Cord feed.
This gives a short circuit path from the charger case to the breaker box and
GFI. This gives you safety should the charger have a issue. This is basicly
required by common sense if not the law.
The DC side should be isolated from the AC side. the two should not touch.
IF they do... you loose the charger.
That said, the DC negative is seprated from the AC by only the rectifiers in
the charger. Like all the other non isolated chargers. Manzanita, Russco,
K&W and all the third world and variac chargers and home builts.
The Positive is the line that gets controlled, throttled, and bucked or
boosted. It is current regulated and voltage controlled. It's the line we
actually do something with. This is protected from shorting by the current
control loops and feedbacks inherent in the design of the charger.
If your pack is properley isolated from chassis, you have no issues, if your
pack is shorted to chassis or you have controller and motor path leaks to
chassis, you will get leakage currents to chassis.
If you charger's case or AC ground is bonded to the chassis of your car...
it will go hot to the touch. If you have a solid ground path, it will not go
hot, but as the leakage gets worse and becomes a hard fault the current
flowing through the leak will become great enough to cause damage sooner or
later.
So keep the pack isolated from the chassis. If's good practice and you need
it anyways.
To limit the current that could flow you need to connect the car chassis to
earth ground in a way that does not pass enough current to cause equipment
damage, but still pass off a few milliamps of leakage current. This gets
really tough when moving 100s of amps of current since transformer actions
can couple a few milliamps to chassis just by having the feed cables get
close to a loop of conductor of some sort. With 3 or so Kw of 120 Hz
ripple....this is getting tough to do with the little chargers also.
What works to give a bleed off path and current limit and indication of
a fault is to have the car chassis connect to the Earth ground by the greed
grounding wire on the DC connector. route this wire through a incandesent
light builb. It will drain the annoyance currents and light up if you have a
hard fault.
Again if your pack and drive is correctly isolated bolting the charger to
the chassis is a safe measure. Adding a negative side contactor to open
negative side of the controller while charging is in progress is the easiest
way to drop the drive system out of the potential leakage loop.
Most DC evs have carbon dust in the motor case, and one lead is hot to
battery even if the drive is unpowered. Key off opens the positve rail, and
if the negative rail also opens it's pretty easy to get zero leakage with
clean batteries.
Rich Rudman
Manzanita Micro
----- Original Message -----
From: "Don Cameron" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, August 23, 2005 2:43 PM
Subject: PFC Ground and Pack Negative (was RE: Russco vs Zivan vs PF)
> Here is what is happening with my PFC:
>
> 1. the PFC case is connected to the the car chassis as per the
instructions
>
> 2. only when the switch is turned on, the case and the car chassis becomes
> pack negative
>
> If the green wire ground is connected to the car chassis, therefore the
pack
> negative is connected to ground.
>
>
>
> I was on the phone to Rich about this a few months back. He indicated that
> this is normal behaviour. Are you telling me there is something wrong
here?
> If so, please clarify how I should test and correct.
>
> Don
>
>
>
>
>
>
>
>
>
>
>
> Victoria, BC, Canada
>
> See the New Beetle EV Conversion Web Site at www.cameronsoftware.com/ev/
> <outbind://18/www.cameronsoftware.com/ev/>
>
> -----Original Message-----
>
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
> <mailto:[EMAIL PROTECTED]> ] On Behalf Of Joe Smalley
>
> Sent: August 22, 2005 10:51 PM
>
> To: ev@listproc.sjsu.edu
>
> Subject: Re: Russco vs Zivan vs PFC
>
> The incoming AC line goes to a full wave bridge rectifier. The negative
side
> of the bridge is connected to Pack Negative.
>
> When the 120 VAC line swings negative, pack negative goes down to -170
volts
> DC for a few milliseconds in a half sine waveform.
>
> When the 120 VAC line swings positive, pack negative sits at -1 Volts DC
for
>
> 8 milliseconds.
>
> The green wire in the AC cord and the DC cord are both connected to
chassis
> ground in the charger.
>
> Neither AC line nor DC line are connected to green wire ground.
>
> The green wire ground is there to safely ground the chassis and blow the
> feed breaker in case there is an isolation breach in the battery pack,
> controller, motor, or charger.
>
> Joe Smalley
>
> Rural Kitsap County WA
>
> Fiesta 48 volts
>
> NEDRA 48 volt street conversion record holder [EMAIL PROTECTED]
>
> ----- Original Message -----
>
> From: "Don Cameron" <[EMAIL PROTECTED]>
>
> To: <ev@listproc.sjsu.edu>
>
> Sent: Monday, August 22, 2005 7:40 PM
>
> Subject: RE: Russco vs Zivan vs PFC
>
>
>
> > This does not sound correct. If the battery pack is isolated from the
>
> > car (which is a good thing). When a PFC charger is turned on, the
>
> > negative
>
> side
>
> > of the pack is grounded to the case of the charger and connected to
>
> > the AC input ground. If the case of the charger is attached to the
>
> > chassis/body
>
> of
>
> > the car, then the chassis/body becomes attached to the negative side
>
> > of
>
> the
>
> > pack.
>
> >
>
> > When the charger is turned off, the pack is not attached to the ground
>
> > of the car.
>
> >
>
> > I have confirmed with Rich that this is the non-isolated behaviour of
>
> > the PFC chargers.
>
> >
>
> > Don
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> >
>
> > Victoria, BC, Canada
>
> >
>
> > See the New Beetle EV Conversion Web Site at
>
> > www.cameronsoftware.com/ev/ <outbind://18/www.cameronsoftware.com/ev/>
>
> >
>
> > -----Original Message-----
>
> > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
> <mailto:[EMAIL PROTECTED]> ]
>
> > On Behalf Of John G. Lussmyer
>
> > Sent: August 22, 2005 6:26 PM
>
> > To: ev@listproc.sjsu.edu
>
> > Subject: Re: Russco vs Zivan vs PFC
>
> >
>
> > At 06:00 PM 8/22/2005, Ryan Stotts wrote:
>
> > >I have the wall and the car and the charger is installed in the car.
>
> > >I plug the charger into the wall and now the car is connected to the
>
> > >power grid. What would the difference be between an isolated charger
>
> > >and a non isolated charger? Because in my mind right now, I don't
>
> > >see how either would be any different.
>
> >
>
> > Well, if your Pack is tied to the Car Body, you have a problem.
>
> > But since sane people do NOT do that, it's not nearly as severed. A
>
> PFC-20
>
> > mounted in the car (to the body) will have the AC Ground line
>
> > connected to the body.
>
> > There IS a connection from a HOT AC line to one end of the pack, but
>
> > since your pack isn't connected to the body, it's relatively safe.
>
> > It's a nice idea to use a GFCI outlet, which will trigger to show you
>
> > when you are getting too much leakage current from your pack....
>
> >
>
> > --
>
> > John G. Lussmyer mailto:[EMAIL PROTECTED]
> <mailto:[EMAIL PROTECTED]>
>
> > Dragons soar and Tigers prowl while I dream....
>
> > http://www.CasaDelGato.com <http://www.casadelgato.com/>
>
> >
>
--- End Message ---
--- Begin Message ---
If you had a way of recapturing vehicle kinetic energy and storing
pressurized hydraulic fluid, either thru simple switches or a
microcontroller, then that would be nice, huh? Like with a tailshaft
mounted pump that recirculated fluid but comes out of bypass and fills
an accumulator to a high pressure when the brake light comes on. And
maintains minimum pressure at other times. Or some variant on this
logic? Just an idea. I know it is not too difficult to implement with a
microcontroller and separate PS pump, but maybe relay logic could do
for the series-wound DC crowd. Or the hairball-equipped?
Seth
On Aug 23, 2005, at 7:56 PM, Tom Shay wrote:
Vehicles with power steering are hard to steer with the power off
because
the gear box or rack-and-pinion has a different gear ratio than a
manual
steering unit. For example, on my 1983 Ranger pickup, the manual box
required almost six turns of the wheel from lock-to-lock compared to
3 1/2 turns for a power steering box. As you'd expect, the power
steering
was quite hard to steer when the truck was not moving and the pump was
turned off. When the truck was moving, steering effort was moderate.
I had a seperate motor for driving the power steering pump and turned
it off
when I didn't need it to conserve battery energy and because the
pump-motor
setup was noisy.
----- Original Message ----- From: "Nick Austin" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, August 23, 2005 3:18 PM
Subject: Re: Power Steering
On Tue, Aug 23, 2005 at 06:13:51PM -0400, Cwarman wrote:
I dont see much mention of power steering pump when doing a
conversion.
I have a 1997 Chevy S10 im tonight pulling the engine out and i left
that portion on for now because wasnt sure if thats something ill
need
or not. Im under the impression that a vehicle made for powersteering
but is unistalled or off turns WAY harder than a truck that is made
without powersteering, is this true ? Any suggestions ?
CWarman
One option to consider is electric power steering, this fits in well
with an EV :)
http://www.nsxprime.com/FAQ/Technical/eps.htm
--- End Message ---
--- Begin Message ---
At 6:53 PM -0700 on 8/22/05, Victor Tikhonov wrote:
John G. Lussmyer wrote:
At 06:25 PM 8/22/2005, Victor Tikhonov wrote:
Can owners tell me what they don't like about their e-meter,
how you'd rather seeit designed or operated?
Which features are lacking and which you consider redundant?
Be able to see Volts and Amps simultaneously.
Update display more than 1/sec.
Warn buzzer for low voltage.
Thanks John!
Does all the above already, so you're covered :-)
Sorry, I don't want to tell yet what else it does
not to bias future opinions for the wish list.
So, anyone else?
Motor and battery temperatures with a overtemp warning/buzzer
user-programmable to a range of temperatures.
--
Auf wiedersehen!
______________________________________________________
"..Um..Something strange happened to me this morning."
"Was it a dream where you see yourself standing in sort
of Sun God robes on a pyramid with a thousand naked
women screaming and throwing little pickles at you?"
"..No."
"Why am I the only person that has that dream?"
-Real Genius
--- End Message ---
--- Begin Message ---
Lee Hart wrote:
> I think I understand. Few people want to spend $10,000 for batteries and
> charger "up front",
And just to further the point. Some people can manage to save up
$1,000. Saving up $10,000 could be 10 times as hard or take 10 times
as long.
It's also all relative. What's expensive to one person, might be
considered cheap to another.
In regards to $20,000 lithium packs, it depends on if the person makes
$20,000 per day, week, or month compared to someone who makes $20,000
a year(or less!) if they are willing to spend that kind of money on a
battery pack.
--- End Message ---
--- Begin Message ---
I have much respect for the efforts of Victor and
John.
I personally really like Victor's name, 'Evision'.
Not sure why John doesn't like this name, maybe he can
provide some insight.
Perhaps others could suggest another name, but this
seems very fitting for the application.
Rod
--- Victor Tikhonov <[EMAIL PROTECTED]> wrote:
> Neon John wrote:
>
> >
> > I hate to say this, Victor, but that name really
> sucks. I have no
> > idea what an Evision is. IMHO, a name ought to
> give some indication
> > of what the product is or does.
> >
> > John
>
> EVision is a gadget providing "Vision" for your EV
> [electrical system]
> - you can "see" how everything is doing. Thus the
> name.
> Take it as E-Vision (instead of E-Meter) if you like
> :-)
>
> I guess, there is no way to please all, some like
> it,
> some don't. How would you name it?
>
> BTW, from the name "Link-10" you can't really tell
> what
> the gadget does. Does this name sucks too then? Just
> wonder.
>
> --
> Victor
> '91 ACRX - something different
>
>
--- End Message ---
--- Begin Message ---
Rush wrote:
Victor,
If you don't already know about 1-wire devices by Dallas Semiconductor, you
might want to check them out.
1-wire is nice,.. especially for a chain of temp sensors and the like.
It is not so useful in a HV application since it is hard to isolate and
one of its biggest features (bus powered devices) goes out the window in
an isolated system.
It does however have a nifty (if somewhat difficult to program) mehod of
auto-detecting what devices are on the wire... and the factory unique
serial numbers can make certain things very easy.
mark farver
--- End Message ---
--- Begin Message ---
Thanks for the input Lee.
The consensus seem to be about everything but display unit.
LEDs are "old" technology (nothing wrong with them in itself).
Not as old as Nixie tubes, so we'll survive :-)
Hard to read at direct sun light.
LCDs are more fragile, but the brighter - the better.
Wide view angle isn't really nesessary - driver's
position is pretty much fixed and you can point the
unit torard you. But the temp affects LCD the most.
There can be 3 small analog (270 degree pointer swing)
gauges with no digital readout at all. No problem with
reading in bright conditions, but of course you loose
precison of a digital display. It is relevant
if you have 216V or 219V, and no analog pointer can
tell you.
So, super bright 7-segment LEDs, LCD, or both?
(you can get and plug either one you like including both
at the same time)?
As far s power for it - shunt circuit gets power from
the pack directly. Display brains - from 12V house power.
No issue to have DC-DC converter off the main pack for that
too.
And, not to worry, you'll get ASCII out Lee. I suppose
no one cares how the modules talk to each other internally.
But I'm afraid if you still run Windows 3.1 you may have
difficuly reading an SD card. This is optional though,
you can always plug RS232 in if dragging a laptop in the car
for some is preferred to taking the card home...
I was assuming that these days it is not an issue to get
some sort of memory card reader for a computer, but may
be naively wrong. Anyway, RS232 will be there (isolated :-)
Victor
Lee Hart wrote:
Victor wrote:
Can owners tell me what they don't like about their e-meter,
how you'd rather see it designed or operated?
Ryan Stotts replied:
I don't own one yet either, but from all I've read about it, it
seems like a finicky, fickle, delicate device. It's also somewhat
expensive. Just how accurate is it anyways?
The E-meter/Link-10 actually *is* a pretty robust and accurate device.
It is certainly a lot better than your typical cheap digital multimeter!
That's why it is relatively expensive. I think the designers of would-be
replacements will have their hands full getting something to work as
well in the presence of the huge amounts of noise in an EV and over the
automotive temperature range.
I think its "reliability" problems are mainly operator miswiring errors.
Remember that it was designed for 12v systems. Its power, voltage sense,
and current sense inputs can easily withstand anything you can do to it
at 12v. But we wire them into high-voltage EVs -- and accidentally
connect the 50mv current sense leads to a 300v pack! No wonder it dies.
To fix this sort of problem, a new design is needed. Rather than depend
on external "band-aid" fixes like the voltage prescaler, DC/DC power
supply, and fuses to protect a 12v meter in a 300v system, it needs to
be a design requirement right up front that "no miswiring in a 500v
system will cause any harm."
I like the 2" round form factor; it's easy to cut a round hole in a dash
to mount it. But I'd prefer that it mount from the front (perhaps with
spring clips on the sides), so you don't have to fish around behind the
panel with the mounting ring.
Als, it should have a connector on the back to connect the wires; not
that fiddly screw terminal block. Yes, I know they wanted screw terminal
so Joe Idiot could wire it with nothing but his swiss army knife. But
they could have used screw terminals on some standard centers so we
could screw a pin header into it, and then plug a Molex or other
connector onto them.
The LED display is ok, but dated. It makes it draw way too much power. I
want a display that is readable at night, in direct sunlight, has a wide
viewing angle, and is large enough to read easily. Modern LEDs can do
this; old ones cannot. LCDs are a (cheap) possibility, but usually have
low contrast and are harder to read under adverse conditions.
I'd eliminate the separate 12 supply, and power it directly from the HV
pack. That requires a reasonably efficient wide-range DC/DC; but that's
do-able nowdays.
Of course it should have an isolated data port; RS-232 or whatever. But
I object to screwy proprietary formats. Give me plain ASCII, not CANbus
or SecretBus.
I think I would prefer a 2-box approach; one box contains all the
high-voltage stuff; shunt, amplifier, prescaler, power supply, and A/D.
This box is equivalent to two ordinary digital multimeters with serial
output; they just send the current and voltage data. The other box is
the display, operator controls, and serial port (and probably the
"brains" to make it work). It integrates this data to give you amphours,
average voltage, state of charge, or whatever.
As for *what* it displays... The E-meter's volts/amps/amphours/time
display is ok for engineers, but useless for the daily driver. The 5-LED
bargraph is just barely adequate as a "fuel" gauge. Probably its best
use for the casual driver is to set the 7-segment display to show "Time
Remaining (minutes at present load current)" or "SOC (0-100%)".
To me, the basic 7-seg display is adequate (save the fancy 9" VGA color
graphic display for the few who want to pay for it). But I would use a
10-bar bargraph for a higher resolution "fuel" gauge. Having it output a
signal to drive a normal car's gas gauge is clever, but I suspect it
will be a difficult problem due to the large differences between cars.
But, I would like a way for the equations that actually decide what gets
displayed to be downloadable. Think of the display head like a
programmable calculator; it accepts data from the volts/amps box, time
from its internal clock, and calculates whatever you want (average
voltage, amphours, Peukert corrected amphours, etc.).
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--
Victor
'91 ACRX - something different
--- End Message ---
--- Begin Message ---
Temp comp the LCD display. Works like a charm and you should never need
to do a contrast adjustment.
Danny
Victor Tikhonov wrote:
LCDs are more fragile, but the brighter - the better.
Wide view angle isn't really nesessary - driver's
position is pretty much fixed and you can point the
unit torard you. But the temp affects LCD the most.
--- End Message ---
--- Begin Message ---
The one car I did with ps , i put a small pulley on the tail shaft and had a
plate that held the pump and bolted on the end of the motor ( where tail
shaft was ) . before end up with this I tried using a small motor that
turned the ps pump and found that when turning the steering wheel it put
Quite a load on the motor . The car as a clutch so one can push on the
clutch and rev the motor to get ps when standing still . it doesn't need
much speed to get the ps working , this wasn't the "perfect " solution but
was easy.
steve clunn
----- Original Message -----
From: "Cwarman" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, August 23, 2005 5:13 PM
Subject: Power Steering
I dont see much mention of power steering pump when doing a conversion. I
have a 1997 Chevy S10 im tonight pulling the engine out and i left that
portion on for now because wasnt sure if thats something ill need or not.
Im under the impression that a vehicle made for powersteering but is
unistalled or off turns WAY harder than a truck that is made without
powersteering, is this true ? Any suggestions ?
CWarman
--- End Message ---
--- Begin Message ---
Cwarman wrote:
> I dont see much mention of power steering pump when doing a conversion.
> I have a 1997 Chevy S10 im tonight pulling the engine out and i left
> that portion on for now because wasnt sure if thats something ill need
> or not. Im under the impression that a vehicle made for powersteering
> but is unistalled or off turns WAY harder than a truck that is made
> without powersteering, is this true ? Any suggestions ?
I'm not sure how stiff the steering will be with that un powered power
gear box. It appears there is a manual gear box for that model truck.
Looks like this:
http://static.summitracing.com/global/images/prod/large/fla-fr1495_w.jpg
Try and get a rebuilt one from the auto parts store or get one from a
junk yard(will be cheapest way). With a proper manual box, it will
feel just like power steering(or very close).
Or if money is no object, get one new:
http://store.summitracing.com/default.asp?target=partdetail.asp&autofilter=1&part=FLA%2DFR1495&N=4294925130+4294839070+4294860446+4294860271&autoview=sku
I had factory power steering on my Mustang. If the pump wasn't
leaking, it would be a hose. If not that, the rack would be leaking
out one end or the other(the bane of hydraulics, leaks). Not to
mention the power it was eating up (15hp?).
I put a manual steering rack on it and I wouldn't have it any other
way. Less maintenance, more power, more room in the engine bay. I
could tell a noticeable performance improvement plus excellent "road
feel". When I drive a power steering car now, it feels twitchy with
no road feel in comparison.
If you insist on keeping your power gear box, get your motor with a
shaft out the front and put a pulley on it and make a mounting bracket
for the pump.
Here's an example using an alternator and AC:
http://electric-echo.com/journal3.htm
Another option would be to get an electric power steering pump off a
Toyota MR2. You'll need a stout DC/DC converter to drive it though.
It pulls some sick amps... no problem though for a gas car with an
alternator. I wouldn't want that draining off my pack though. Ever
leave your lights on and seen how quick that drains a battery? I
suppose one could put a switch on it and cut power to it when going
straight for extended periods of time though..
http://www.driveev.com/jeepev/convpgs/psteer.php
Simplest way would be to call up local junk yards and tell them you
need a manual steering gear box for a '97 S10 and swap it out.. Or
get a rebuilt one from a auto parts store.
--- End Message ---
