# [evdl] Gauges For My Ev?



## EVDL List (Jul 27, 2007)

I'm having a little trouble sorting out what I need as far as gauges for my S-10 conversion. Does anyone have any suggestions as to what works best? I guess I would like to have a little computer screen, RPM, Miles/Hr, battery pak voltage, Watt/Hrs used, etc. But I'm not sure what is available, I've been looking at stuff on the web so long, I've gotton myself confused. 

Thanks

Josh

www.jcsevparts.com
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## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

Hi Josh;

I'm old fashioned a bit here. I like plain old analog type panel meters. 
Large format3-4" square. Usually install 12 volt "Grain of Wheat" type 
bulbs, you model RR guyz know them. Any Hobby shop that sells parts would 
know them, glue two of them inside the meter faces area. put them in series 
so the'll last forever.I'm surprised at the relative lack of selection at 
the EV parts depts. E Bay has a selection of stuff, IF you have time to wade 
through it!? Got 3 600 amp Miller meters from welding gear? for 12 bux each. 
Of course yur not done<g>! Gotta hunt down some 600 amp SHUNTS! Found them, 
too. Shunts were cheep, too.All Electronics in CA. Volt meters, too, same 
hunt thing!IF ya have a GOOD quality meter, like say, a Simpson, 60-70 bux, 
nowadaze, you can get used to how your volts read, or how far yur gunna go! 
Sorta like a sailer reads the wind on a sailboat, to trim his sails. Yur Amp 
meter helps too, between the two you WILL learn how far yur going! How 
"Soft" the pack is getting, FAR from home<g>!

OK that's my "Beginner" pack. Read all that OTHER stuff, too. But don't 
go crazy. Christ! There are ENOUGH diss-tractions driving nowadaze. Case in 
point; Radios, that you need an engineering degree to operate! Just to turn 
on, tune, you have to look at and diddle, you will not see the broad in the 
Escalade on the fone blowing by the STOP sign, to take evasive action! I 
sorta like my dashbored PLAIN, to keep an eye on traffic and the stupid shit 
EVerybody else is pulling.

YMMV, though.

Bob
----- Original Message ----- 
From: "Josh Creel" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, February 04, 2008 8:44 AM
Subject: [EVDL] GAUGES FOR MY EV?


> I'm having a little trouble sorting out what I need as far as gauges for 
> my S-10 conversion. Does anyone have any suggestions as to what works 
> best? I guess I would like to have a little computer screen, RPM, 
> Miles/Hr, battery pak voltage, Watt/Hrs used, etc. But I'm not sure what 
> is available, I've been looking at stuff on the web so long, I've gotton 
> myself confused.
>
> Thanks
>
> Josh
>
> www.jcsevparts.com
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>
>
> -- 
> Internal Virus Database is out-of-date.
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> 9/22/2007 1:27 PM
>
> 

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

Josh,

I use an analog ammeter and voltmeter mounted in plain view. You can calculate max speed in each gear so as to not overspeed your motor, so you don't necessarily need motor RPM (although this would be cool). You can also use an E-Meter to keep track of AH out and AH in. I think the ammeter and voltmeter are minimum requirements.

Devices like PakTrakr (?), EVision add capability but I don't feel I need them at this point.


----- Original Message ----
From: Josh Creel <[email protected]>
To: Electric Vehicle Discussion List <[email protected]>
Sent: Monday, February 4, 2008 8:44:02 AM
Subject: [EVDL] GAUGES FOR MY EV?


I'm 
having 
a 
little 
trouble 
sorting 
out 
what 
I 
need 
as 
far 
as 
gauges 
for 
my 
S-10 
conversion. 
Does 
anyone 
have 
any 
suggestions 
as 
to 
what 
works 
best? 
I 
guess 
I 
would 
like 
to 
have 
a 
little 
computer 
screen, 
RPM, 
Miles/Hr, 
battery 
pak 
voltage, 
Watt/Hrs 
used, 
etc. 
But 
I'm 
not 
sure 
what 
is 
available, 
I've 
been 
looking 
at 
stuff 
on 
the 
web 
so 
long, 
I've 
gotton 
myself 
confused. 

Thanks

Josh

www.jcsevparts.com
_______________________________________________
For 
subscription 
options, 
see
http://lists.sjsu.edu/mailman/listinfo/ev





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----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

Hello Josh,

I find that the most important gage for a EV is the motor amp meter. This 
gage takes off the a shunt that is install between the controller and the 
motor.

Next is the battery amps which is taken from a shunt between the battery and 
the main contactor.

Lets say your motor is rated for a continuous ampere of 200 amps, a battery 
ampere meter will not read that. The battery amps may be reading 50 amps 
while your motor may be at 200 amps.

Thinking your batteries are rated for 800 amps and you running the battery 
ampere at 200 amps, your motor amperes could be way over 600 amps.

A motor like a ADC and Warp can only with stand a short burst of over ampere 
for a short time, so motor ampere is the one to watch. Many people have 
overheat or burn out there motors because motor indications was not use.

The next meter is a meter to find out how much energy is use from the 
battery and replacing that energy to the correct level and at what rate.

This would be like a E-Meter such as a Link-10. It reads the amount of 
ampere-hour use and recharge, it also records the amount of watthours, 
battery amperes, battery voltage, percentage of charge and battery 
temperature.

The next meter would be a tachometer, so you do not over speed the motor. 
Some controllers, have a speed sensor input where you input the maximum rpm 
of the motor.

If you do not have a tachometer for now, here is a formula you can use to 
find out what the maximum mph in each gear would be:


RPM x Tire Circumference
MPH = -------------------------
Overall Gear Ratio x 1056

The Overall Gear Ratio is axle ratio times the transmission gear ratio in a 
selected gear.

The Tire Circumference is the one rolling turn with the weight of the 
vehicle on the tire. Is measure by placing a mark on the tire and the 
ground and make one rotation and placing another mark on the ground. Then 
measure between the two marks.

For example, my motor maximum rpm is 6000 rpm and my tire circumference is 
90 inches. My rear axle is 5.57:1 and if I want to find out how fast I can 
go in 1st gear which my is a 2.75:1, then to find the overall ratio, I take 
5.57:1 times 2.75:1 = 15.3175:1 overall ratio.

So in 1st gear this becomes:


6000 rpm x 90 inches
33.3 MPH = --------------------
15.3175 x 1056

Therefore I will normally not go over 30 mph in 1st gear. You then can 
calculated what the maximum speed you can go in all the other gears.

Roland

> ----- Original Message ----
> From: Josh Creel <[email protected]>
> To: Electric Vehicle Discussion List <[email protected]>
> Sent: Monday, February 4, 2008 8:44:02 AM
> Subject: [EVDL] GAUGES FOR MY EV? 

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

Hi Roland,

My car uses an automatic transmission so I was planning to look at motor current to find the shift points. What do you think of that approach?

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




> ---- Roland Wiench <[email protected]> wrote:
> > Hello Josh,
> >
> > I find that the most important gage for a EV is the motor amp meter. This
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Josh Creel wrote:
> > I'm having a little trouble sorting out what I need as far as gauges
> > for my S-10 conversion. Does anyone have any suggestions as to what
> > works best? I guess I would like to have a little computer screen,
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

Hello Mark,

I have use both type of transmissions. It was first a GM TH-350 with and 
then without the torque converter. The clutches only lasted 1000 miles with 
out the torque converter. I now use a GM TH-400 TCI automatic that is 
converted to manual using a manual value body which is a shift only 
transmission like a manual.

I use the large 4 inch tachometer that is converted to a motor ampere meter 
by programming the Zilla for AMP ON TACH which I can read the motor ampere 
on the tachometer.

I can pull away from 0 mph at a normal street acceleration and can keep it 
at 200 motor amps on a level grade. If there is a slight up hill grade, it 
may go to 300 amps while holding the accelerator peddle at one constant 
position.

I find as the speed increases from 0 to 30 mph on this slight up hill grade, 
the motor ampere will go from 0 to 300 amps, and as it hits 300 amps, and 
even while the speed is increasing, the motor ampere is now dropping from 
300 amps back to 200 amps.

Now if the EV happens to be on level grade and then the GE 11 inch motor 
will come down to 150 motor ampere while my battery ampere is about 50 amps.

Before I had a motor ampere meter install, I really cook the motor windings 
to a nice dark brown color by just watching a battery ampere which read 180 
battery amperes and the battery voltage was at 170 volts.

I found out, later when I install a motor amp meter, that I was pulling 
about 600 motor ampere! on a long 2 mile up grade hill that ran for about 10 
years. I had a motor shop re enamel the windings and was able to run 
another 15 years, until a silver solder welded connection came apart and had 
that repair and re enamel again.

Using a motor amp meter, I now keep the GE-11 motor ampere to about a 175 
amps normal running and the battery amperes at a 40 amps normal running at 
30 mph.

The Warp 9 motor which I use as a back up spare motor, will run at 200 motor 
amps at about 50 battery amps for the same speed.

Roland


----- Original Message ----- 
From: "Mark Ward" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Cc: "Roland Wiench" <[email protected]>
Sent: Monday, February 04, 2008 8:42 AM
Subject: Re: [EVDL] GAUGES FOR MY EV?


> Hi Roland,
>
> My car uses an automatic transmission so I was planning to look at motor 
> current to find the shift points. What do you think of that approach?
>
> Mark Ward
> 95 Saab 900 SE "Saabrina"
> www.saabrina.blogspot.com
>
>


> > ---- Roland Wiench <[email protected]> wrote:
> > > Hello Josh,
> > >
> > > I find that the most important gage for a EV is the motor amp meter.
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Lee Hart wrote:
> 
> > The absolute minimum is an analog ammeter (battery amps) and
> > voltmeter (battery volts). An expanded scale voltmeter is
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Roger Stockton wrote:
> > I'd suggest that if you have a modern controller then the absolute
> > minimum is a voltmeter on the battery pack...
> 
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Lee Hart wrote:
> 
> > You still need the ammeter, because voltage without knowing
> > current is largely meaningless.
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Josh Creel wrote:
> 
> > I'm having a little trouble sorting out what I need as far as
> > gauges for my S-10 conversion. Does anyone have any suggestions as
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

When I contacted Otmar at Caf=E9 Electric about a Zilla, he ask me what typ=
e =

of EV do I have. So I email him some photos of my EV and looking at the =

dash, he said, where is your motor amp meter and how much battery ampere do =

you normally pull?

I said, this is a triac Cable Form controller, and the amp meter shunt is i=
n =

series in the battery positive line that goes directly to the A1 motor =

terminal. The battery negative goes to the main contactor that has a 300 am=
p =

free wheel diode across it and then goes to the controller.

Otmar said the ampere will be different between the free wheel diode and th=
e =

motor. This is the motor ampere which will be more than the battery ampere.

I said I normally pull 180 amps and some times 600 amps going up a steep 2 =

mile hill to work every day. Otmar said to install a motor amp meter to se=
e =

what the motor pulls, so we know if you need a Zilla 1k or a Zilla 2k. So =
I =

did.

I took a test run up a slightly up grade hill that was 3 miles long, holdin=
g =

the battery ampere to 90 amperes, and the about 300 motor amps at 30 mph at =

6000 rpm. So this is the ratio between the battery and motor ampere of =

about 3 to 1.

Otmar then said you will need a Zilla 2k to be able to pull that 2 mile =

steep hill which you may get over 300 batteries amps. I said that is true, =

if I keep it in final gear.

I said I will be retire by the time I modified these rig with a Zilla, so I =

will not travel up the hill to work any longer. All my normal driving is in =

city driving, which I now keep the continuous motor ampere at 200 amps and =

the battery ampere of 75 amps.

So I choose a Zilla 1K because I would have to make the EV bigger to get it =

in. The Zilla 2K which I would like to have, would not fit in anyplace.

If you know what the ratio between your battery ampere and motor ampere, =

with the type of motor controller you have, then you could RED LINE a =

battery amp meter, to stay at a safe motor ampere.

Roland


----- Original Message ----- =

From: "Lee Hart" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, February 04, 2008 4:04 PM
Subject: Re: [EVDL] GAUGES FOR MY EV?




> > Roger Stockton wrote:
> > > I'd suggest that if you have a modern controller then the absolute
> > > minimum is a voltmeter on the battery pack...
> >
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Roland Wiench <[email protected]> wrote:
> 
> > If you know what the ratio between your battery ampere and motor ampere,
> > with the type of motor controller you have, then you could RED LINE a
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Roland Wiench wrote:
> 
> > I took a test run up a slightly up grade hill that was 3
> > miles long, holding the battery ampere to 90 amperes, and the
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

`That is true if you apply more torque at the slow speed, but I do not do 
that, because I reduce my torque by shifting down. In final gear it will 
start to become even if it can go that fast.

Here is the results in each gear that I record with my manual transmission 
using a GE-11 motor at 6000 rpm.

1st gear ratio of 19.495:1 at 6000 rpm at 25 mph equals 161 motor amps at 65 
battery amps.

2nd gear ratio of 13.925:1 at 6000 rpm at 35 mph equals 230 motor amps at 75 
battery amps.

3rd gear ratio of 5.57:1 at 4000 rpm at 60 mph equals 300 motor amps with 
a battery ampere of 250 amps which is now becoming closer.

The estimate torque at very low speed of 10 mph is about 8 ft-lbs in 1st 
gear and becomes about 50 ft-lbs at 60 mph in final gear.

Roland


----- Original Message ----- 
From: "Morgan LaMoore" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Monday, February 04, 2008 5:02 PM
Subject: Re: [EVDL] GAUGES FOR MY EV?


>


> Roland Wiench <[email protected]> wrote:
> >
> > > If you know what the ratio between your battery ampere and motor ampere,
> > > with the type of motor controller you have, then you could RED LINE a
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

Don't have a controller yet, I'm thinking of taking a chance on the new 
Kelly, but may go with the Curtis. Not sure yet, still trying to make up 
my mind. Like to have anyone's insight on this as well, although I've read 
a lot of opinions on this list already. 

> I'd suggest that if you have a modern controller then the absolute minimum 
> is a voltmeter on the battery pack. If the meter is analog, then expanded 
> scale is pretty much essential, but if it is digital (e.g. just a DMM 
> situated conveniently) you don't need an expanded scale.
>
> If you have a contactor controller where *you* must control the current, 
> then I would agree that a battery ammeter and voltmeter are the bare 
> minimum.
>
> Cheers,
>
> Roger.
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev 

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

From: Roger Stockton
> You've been driving with too many guages for too long! ;^>

That's possible.  Our standards rise as we learn more.

> Voltage on its own is *very* useful...

You can get by without an ammeter as you say, only knowing when the pack reaches dead at 1.75v/cell. But it will be difficult to judge how much farther you can go. You won't be able to measure efficiency, to tell, for instance that your brakes are dragging. You will also have trouble charging, unless you have a fully automatic (and trustworthy) charger.

The only thing new is the history you don't know yet. -- Harry Truman
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart-at-earthlink.net

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

To 
add 
to 
Lee's 
point, 
the 
only 
way 
to 
know 
that 
you're 
not 
killing 
the 
batteries 
every 
time 
you 
drive 
is 
to 
know 
how 
much 
current 
you're 
asking 
them 
to 
deliver. 
Very 
small 
changes 
in 
control 
input 
can 
make 
large 
differences 
in 
battery 
amp 
draw. 
Every 
vehicle 
will 
be 
different 
of 
course, 
but 
I 
don't 
know 
why 
you 
wouldn't 
install 
an 
ammeter; 
they're 
cheap 
and 
very 
worthwhile. 
Think 
of 
it 
as 
a 
way 
to 
protect 
your 
investment 
in 
batteries.


----- Original Message ----
From: Lee Hart <[email protected]>
Subject: Re: [EVDL] GAUGES FOR MY EV?

You 
can 
get 
by 
without 
an 
ammeter 
as 
you 
say, 
only 
knowing 
when 
the 
pack 
reaches 
dead 
at 
1.75v/cell. 
But 
it 
will 
be 
difficult 
to 
judge 
how 
much 
farther 
you 
can 
go. 
You 
won't 
be 
able 
to 
measure 
efficiency, 
to 
tell, 
for 
instance 
that 
your 
brakes 
are 
dragging. 
You 
will 
also 
have 
trouble 
charging, 
unless 
you 
have 
a 
fully 
automatic 
(and 
trustworthy) 
charger.





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## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Lee Hart wrote:
> 
> > That's possible.  Our standards rise as we learn more.
> 
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Andre' Blanchard wrote:
> 
> > The ampmeter will tell you that the voltage drop is because
> > you have a cell or three going soft someplace in the pack
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Josh Creel wrote:
> 
> > Don't have a controller yet, I'm thinking of taking a chance
> > on the new Kelly, but may go with the Curtis. Not sure yet,
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

I am not saying that Kelly controllers are good or bad I just know the guy
with that conversion and there other factors at this time that could be
impacting his speed.
For one the brushes are not worn in yet.


-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf
Of Roger Stockton
Sent: Tuesday, February 05, 2008 5:36 PM
To: 'Electric Vehicle Discussion List'
Subject: Re: [EVDL] GAUGES FOR MY EV?



> Josh Creel wrote:
> 
> > Don't have a controller yet, I'm thinking of taking a chance
> > on the new Kelly, but may go with the Curtis. Not sure yet,
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

>> You can get by without an ammeter as you say, only knowing
>> when the pack reaches dead at 1.75v/cell. But it will be
>> difficult to judge how much farther you can go.
> I'm not sure I understand how an ammeter would help in this regard

Easy... My controller lights an LED when it sees my battery pack hit 
1.75V/cell. When accelerating from a stop I may see this LED flash. As the 
%SOC drops, the LED will flash more often and at lower battery amps.

For a quick battery charge indication I press the accelerator just hard 
enough to light this LED and glance at the battery amps. >300A? 250A? No 
problem. If the LED lights at 200A or less I know it'll be a slow trip 
home 

In my case, the LED is a remote indication of battery voltage. You can do 
the same thing by watching the battery voltage gauge while pressing the 
accelerator. The LED just lets me keep both eyes on the road!

-Adrian

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

Hi Roland,

You give the gear reduction but make the reader figure out your tire 
size! I mention that because I got a couple of cars (an EV and a 
conversion in progress) where the results are very different. The 
Datsun has taller gears - but more motor rpm per MPH in each gear. 
The VW Buggy has lower gears but less rpm per MPH in each gear. The 
difference is tire size - the buggy runs P225/75R15 tires and the 
Datsun P165/80R13 tires.

BTW - your tires are about 27.3 inches tall 

Paul

P.S. - I want to thank you for your contributions to this list.

> 1st gear ratio of 19.495:1 at 6000 rpm at 25 mph equals 161 motor 
> amps at 65
> battery amps.
>
> 2nd gear ratio of 13.925:1 at 6000 rpm at 35 mph equals 230 motor 
> amps at 75
> battery amps.
>
> 3rd gear ratio of 5.57:1 at 4000 rpm at 60 mph equals 300 motor 
> amps with
> a battery ampere of 250 amps which is now becoming closer.

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

Paul,



> Paul <[email protected]> wrote:
> > Hi Roland,
> >
> > You give the gear reduction but make the reader figure out your tire
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

The formula is: 


Mph=(rpm x tire circumference)/(overall ratio x 1056) 

26.2 mph =(6000 x 90)/(19.495 x 1056)

Roland 


----- Original Message ----- 
From: "David Nelson" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Tuesday, February 05, 2008 8:06 PM
Subject: Re: [EVDL] GAUGES FOR MY EV?


> Paul,
> 
>


> Paul <[email protected]> wrote:
> > > Hi Roland,
> > >
> > > You give the gear reduction but make the reader figure out your tire
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Lee Hart wrote:
> >> You can get by without an ammeter... But it will be
> >> difficult to judge how much farther you can go.
> 
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

I am surprised the cross needle meter hasn't come up again, I think it
is an elegant solution.

http://www.qsl.net/k5lxp/ev/evgauge/evgauge.html



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## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*



> Jeff Shanab wrote:
> > I am surprised the cross needle meter hasn't come up again, I think it
> > is an elegant solution.
> > http://www.qsl.net/k5lxp/ev/evgauge/evgauge.html
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

Here is the battery amp and volt meter as display at:

http://to-ev.net/pics/020.html

The meters indicates this display when the EV ignition is turn off.

When the ignition switch is turn on, the amp meter will read 0 amps and volt 
meter will read about 200 volts.

As load is increase, the ampere will rise to about 180 amps while the 
voltage drops to 170 volts at about 60 mph.

If I hold this speed of 60 mph up a very steep hill, the ampere could go to 
600 amps, while the voltage drops to 150 volts.

Now if I continue to drive until the vehicle can not go any more, the 
voltage will display 150 volts at 0 amps which is the same indications as if 
I had the ignition switch off.

The above indications are with a set of 300 AH cells. Now switching to 200 
AH cells, the battery amps now become 260 amperes at 150 volts at 60 mph 
(not hill climbing).

It becomes worst with 100 AH cells.

So how do I know what the ampere would be of a battery pack if I look at a 
150 volt indication. Is it 0 amps, 250 amps or 600 amps?

It has to be determine by how many miles you travel and/or how long ago you 
charge the batteries. After awhile you can determine this by the history of 
your driving with a volt meter.

I have only use these two meters for about 25 years, which have cause me to 
over ampere my motor many times. The field coils which are space on 
insulated square rods had to be re-enamel.

Roland






----- Original Message ----- 
From: "Lee Hart" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Thursday, February 07, 2008 7:36 AM
Subject: Re: [EVDL] GAUGES FOR MY EV?




> > Jeff Shanab wrote:
> > > I am surprised the cross needle meter hasn't come up again, I think it
> > > is an elegant solution.
> > > http://www.qsl.net/k5lxp/ev/evgauge/evgauge.html
> ...


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## EVDL List (Jul 27, 2007)

*Re: [EVDL] GAUGES FOR MY EV?*

On the small end, I would like to make a link 10 like device that has a
graphic display that displays the cross needle guage as one of it's modes.

On the big end, I have planned on providing this widget in my digital
dash design, where it would just be a software tweak.

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